From dce1a2a6ecd9971433b4ee24c9d36b124cc1280e Mon Sep 17 00:00:00 2001
From: Norbert Preining <norbert@preining.info>
Date: Wed, 29 Dec 2021 03:01:06 +0000
Subject: CTAN sync 202112290301

---
 graphics/pgf/contrib/yquant/README.md              |   17 +-
 graphics/pgf/contrib/yquant/doc/yquant-doc.pdf     |  Bin 712093 -> 994303 bytes
 graphics/pgf/contrib/yquant/doc/yquant-doc.tex     | 1938 ++++++++++++++++++--
 graphics/pgf/contrib/yquant/tex/yquant-circuit.tex |   32 +-
 graphics/pgf/contrib/yquant/tex/yquant-config.tex  |   35 +-
 graphics/pgf/contrib/yquant/tex/yquant-env.tex     |  303 ++-
 graphics/pgf/contrib/yquant/tex/yquant-lang.tex    |   15 +-
 graphics/pgf/contrib/yquant/tex/yquant-prepare.tex |    2 +-
 .../pgf/contrib/yquant/tex/yquant-registers.tex    |   63 +-
 graphics/pgf/contrib/yquant/tex/yquant-shapes.tex  |    7 +-
 graphics/pgf/contrib/yquant/tex/yquant-tools.tex   |    2 +
 graphics/pgf/contrib/yquant/tex/yquant.sty         |    8 +-
 .../contrib/yquant/tex/yquantlanguage-groups.sty   |    8 +-
 .../pgf/contrib/yquant/tex/yquantlanguage-qasm.sty |   12 +-
 14 files changed, 2203 insertions(+), 239 deletions(-)

(limited to 'graphics/pgf')

diff --git a/graphics/pgf/contrib/yquant/README.md b/graphics/pgf/contrib/yquant/README.md
index 724ab32711..93e177ca28 100644
--- a/graphics/pgf/contrib/yquant/README.md
+++ b/graphics/pgf/contrib/yquant/README.md
@@ -5,9 +5,24 @@ yquant is a LaTeX package that allows to quickly draw quantum circuits. It bridg
 yquant is a pure-LaTeX solution - i.e., it requires no external program - that introduces a logic oriented language and thus brings the best of both worlds together.
 It builds on and interacts with TiKZ, which brings an enourmous flexibility for customization of individual circuit.
 
+Important features in the latest updates (for a much more complete list, see the documentation):
+- Support the `beamer` package (since 0.6)
+- New `text` gate, which replaces the common `[draw=none] box` situation (since 0.6)
+- Integration of all qpic examples in the manual, showcasing some very advanced circuits (since 0.6)
+- Simple interface for circuit equations, no more `subcircuit` hassling (since 0.5)
+- Measurement outputs can now directly control other gates, i.e., with a vertical classical line emanating from the measurement (since 0.4)
+- Automatically adjust vertical positions of wires also for multi-register gates (since 0.4-alpha)
+- Vertical alignment actually works for subcircuits (since 0.4-alpha)
+- Directly support circuits written in the `qasm` language (since 0.3)
+- Simple declaration of custom gates (since 0.2.1)
+- Support for subcircuits, though vertical alignment may be messed up (since 0.2)
+- Load circuits from files (since 0.2)
+- Native support for non-contiguous multi-qubit gates (since 0.1.2)
+- Extensive user-friendly support for register name ranges, lists (since 0.1.1)
+
 A detailed reference with lots of examples is provided in the PDF version of this Readme. We will sketch some basic usage.
 
-Now yquant also understands circuits written in the qasm language and provides a simple interface for circuit equations!
+The arXiv runs on version 0.3.2 - please download the latest version from the releases section and include it in your submission.
 
 Support the development:
 - [![PayPal](https://img.shields.io/badge/donate-via%20PayPal-blue.svg?style=flat)](https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=UTR3MRBYJ825A&source=url)
diff --git a/graphics/pgf/contrib/yquant/doc/yquant-doc.pdf b/graphics/pgf/contrib/yquant/doc/yquant-doc.pdf
index baca7da540..9fefce4faf 100644
Binary files a/graphics/pgf/contrib/yquant/doc/yquant-doc.pdf and b/graphics/pgf/contrib/yquant/doc/yquant-doc.pdf differ
diff --git a/graphics/pgf/contrib/yquant/doc/yquant-doc.tex b/graphics/pgf/contrib/yquant/doc/yquant-doc.tex
index b6c5e3057f..ac027a7101 100644
--- a/graphics/pgf/contrib/yquant/doc/yquant-doc.tex
+++ b/graphics/pgf/contrib/yquant/doc/yquant-doc.tex
@@ -190,6 +190,8 @@
 \def\ee{{\symup e}}
 \def\ketbra#1#2{\ket{#1}\!\bra{#2}}
 
+\robustify\bmod % unicode-math makes problems when \bmod is used within a box
+
 \frenchspacing
 \RequirePackage{scrlayer-scrpage,scrlayer-notecolumn}
 \setcounter{tocdepth}{\subsectiontocdepth}
@@ -209,7 +211,7 @@
       \noindent This manual introduces \Yquant, a \LaTeX\hyp only package that outputs quantum circuits.
       They are entered using a human\hyp readable language that, even from the source code, allows for a fluent understanding of the logic that underlies the circuit.
       \Yquant{} internally builds on \TikZ{} and can be easily combined with arbitrary \LaTeX{} code.
-      More than fifty pages of examples complement the formal manual.
+      Almost one hundred pages of examples complement the formal manual.
    \end{abstract}
    \tableofcontents
 
@@ -217,7 +219,7 @@
       This document outlines the scope and usage of the \Yquant{} package.
       It contains both a reference and a huge number of examples.
       \Yquant{} is a package that makes typesetting quantum circuits easy; the package is available on CTAN.
-      This beta version~0.5.1 \emph{should} be stable and interfaces are not very likely to change in an incompatible way in the future.
+      This beta version~0.6 \emph{should} be stable and interfaces are not very likely to change in an incompatible way in the future.
       \compat{New in 0.4}Sometimes, backwards\hyp incompatible changes are required or advisable, in which case a compatibility setting will allow to revert back to the old behavior (rather, to maximize compatibility, this is an opt\hyp in setting: unless you choose the new behavior, you will get the old one).
       Please do report all issues and desirable additions on \href{https://github.com/projekter/yquant/issues}{GitHub}.
 
@@ -265,7 +267,7 @@
                      Additionally, the \tex!\xymatrix! syntax is also somewhat cryptic.
                      \pkg{qcircuit} provides some flexibility within the limits of \pkg{xy} as to configuring the output.
 
-                     Maintenance status: last update in 2018; and remember this is \pkg{xy} based, with last update in 2013.
+                     Maintenance status: active (\href{https://github.com/CQuIC/qcircuit}{GitHub}); but remember this is \pkg{xy} based, with last update in 2013.
                   \item \pkg{quantikz} is a relatively recent package that, following the same grid\hyp based approach as \pkg{qcircuit}, instead builds on \TikZ{} as a backend.
                      As a consequence, it provides the full flexibility of customization that \TikZ{} offers, where hardly anything cannot be done.
                      It also reduces burdens of the \pkg{xy} syntax.
@@ -341,9 +343,9 @@
             When starting a new document, it is recommended to leave out the compatibility key at first compilation.
             \Yquant{} will then issue a warning from which you can infer the recommended setting, corresponding to the current version.
             You should then pass the appropriate version to the \tex!\usepackage! command.
-            For example, this manual corresponds to \tex!\usepackage[compat=0.4]{yquant}!.
+            For example, this manual corresponds to \tex!\usepackage[compat=0.6]{yquant}!.
 
-            Allowed values for \texttt{compat} are \texttt{newest} (discouraged), which equals \texttt{0.4}, and \texttt{0.3} (default).
+            Allowed values for \texttt{compat} are \texttt{newest} (discouraged), which equals \texttt{0.6}, \texttt{0.4}, and \texttt{0.3} (default).
          \end{warning}
 
       \subsection{Starred vs. unstarred environment}
@@ -575,7 +577,8 @@ IndexSingle = ?number? | ( [ ?number? ], "-", [ ?number? ] );
                Note that \texttt{<name>} is case\hyp insensitive and may not contain spaces.
                Special characters are allowed if \TeX{} can cope with them (i.e., no comment signs, no unbalanced braces, no backslashes...).
             \item They create a style \style{/yquant/operators/every <name>} and assign the optional \texttt{<style>} to it.
-               If no style is provided, the default style will inherit from \style{/yquant/operators/every box}.
+               If no style is provided, the default style will inherit from \style{/yquant/operators/every rectangular box}\compat{Changed in 0.6}.
+               If a \texttt{compat} version before \texttt{0.6} is chosen, \style{/yquant/operators/every box} will instead be the ancestor.
             \item They define \texttt{<content>} to be the value that is written into the box.
                This \texttt{<content>} is expanded in a protected manner at the time of gate declaration.
                You may need to prefix fragile macros by \tex!\protect!.
@@ -691,6 +694,12 @@ IndexSingle = ?number? | ( [ ?number? ], "-", [ ?number? ] );
             \end{itemize}
          \end{option}
 
+         \begin{option}[New in 0.6]{register/default lazy name}!!
+            The printed name that is used by default if a new register is created implicitly (i.e., without using any of \gate{qubit}, \gate{cbit}, \gate{qubits}, or \gate{nobit}, but inside a \texttt{yquant*} environment by just using the register).
+            The same macros as with \style{/yquant/register/default name} are available.
+            Note that this default setting is not used when the register is created via an \gate{init} gate---its value always overwrites the default.
+         \end{option}
+
          \begin{option}[Changed in 0.4]{every label}!shape=yquant-init, anchor=center, align=right, outer xsep=2pt, /yquant/operator/if multi={draw, decoration={gapped brace, mirror, raise=2pt}, decorate}!
             This style is installed for every single register name label (i.e., upon creation and when used with the \gate{init} gate).
             The default style allows to use line breaks in the labels.
@@ -877,8 +886,10 @@ IndexSingle = ?number? | ( [ ?number? ], "-", [ ?number? ] );
             Note that the \texttt{shorten} keys are only present in the default style if you specify at least the compatibility version \texttt{0.4}.
          \end{option}
 
-         \begin{option}{operators/every box}!shape=yquant-rectangle, draw, align=center, inner xsep=1mm, x radius=2mm, y radius=2.47mm!
+         \begin{option}[Changed in 0.6]{operators/every box}!/yquant/operators/every rectangular box!
             This style is installed for every \gate{box} operator.
+            Note that with a \texttt{compat} setting strictly smaller than~\texttt{0.6}, the definition of this style was the one that is now \style{/yquant/operators/every rectangular box}, and this style was also the base style from which all box\hyp like gates inherited.
+            With a \texttt{compat} setting of at least~\texttt{0.6}, no other gates apart from \gate{box} will use this style directly or indirectly.
          \end{option}
 
          \begin{option}[Changed in 0.4\\New in 0.2]{operators/every custom gate}!/yquant/operators/subcircuit/seamless!
@@ -893,7 +904,7 @@ IndexSingle = ?number? | ( [ ?number? ], "-", [ ?number? ] );
             The \texttt{yquant-dmeter} shape consists of a rectangle whose right side is replaced by a circle, resembling the letter ``D.''
          \end{option}
 
-         \begin{option}{operators/every h}!/yquant/operators/every box!
+         \begin{option}{operators/every h}!/yquant/operators/every rectangular box!
             This style is installed for every \gate{h} (Hadamard) operator.
          \end{option}
 
@@ -918,7 +929,7 @@ IndexSingle = ?number? | ( [ ?number? ], "-", [ ?number? ] );
             The \texttt{yquant-oplus} shape resembles the addition\hyp modulo\hyp two symbol $\oplus$.
          \end{option}
 
-         \begin{option}{operators/every pauli}!/yquant/operators/every box!
+         \begin{option}{operators/every pauli}!/yquant/operators/every rectangular box!
             This style is installed for every Pauli operator, i.e., \gate{x}, \gate{y}, and \gate{z}.
          \end{option}
 
@@ -926,6 +937,11 @@ IndexSingle = ?number? | ( [ ?number? ], "-", [ ?number? ] );
             This style is installed for every \gate{phase} gate $\ketbra00 + \ee^{\ii\phi} \ketbra11$.
          \end{option}
 
+         \begin{option}[New in 0.6]{operators/every rectangular box}!shape=yquant-rectangle, draw, align=center, inner xsep=1mm, x radius=2mm, y radius=2.47mm!
+            This style is not associated to any particular gate, but will be inherited by a lot of gates that have a rectangular box frame with some text.
+            This style should not be used with a \texttt{compat} setting strictly smaller than~\texttt{0.6}.
+         \end{option}
+
          \begin{option}{operators/every slash}!shape=yquant-slash, x radius=.5mm, y radius=.7mm, draw!
             This style is installed for every \gate{slash} pseudo\hyp gate, i.e., the one that is used to indicate that a single register line actually denotes multiple registers.
          \end{option}
@@ -1004,6 +1020,10 @@ IndexSingle = ?number? | ( [ ?number? ], "-", [ ?number? ] );
             The \texttt{yquant-swap} shape consists of a single cross.
          \end{option}
 
+         \begin{option}[New in 0.6]{operators/every text}!shape=yquant-rectangle, align=center, inner xsep=1mm, x radius=2mm, y radius=2.47mm!
+            This style is installed for every \gate{text} gate.
+         \end{option}
+
          \begin{option}[New in 0.1.2]{operators/every wave}!shape=yquant-circle, radius=.5mm, fill!
             This style is installed for every \gate{correlate} gate.
          \end{option}
@@ -1054,10 +1074,10 @@ IndexSingle = ?number? | ( [ ?number? ], "-", [ ?number? ] );
          For nested subcircuits, you will get multiple prefixes.
          \compat{New in 0.5}The prefixing behavior can be influenced by \style{/yquant/operators/subcircuit/name mangling}.
 
-      \subsection{Shapes and the drawing pipeline}
+      \subsection{Shapes and the drawing pipeline}\label{sec:pipeline}
          All \Yquant{} shapes have the anchors available you would typically expect from a \TikZ{} shape of the given outline.
          The \texttt{center} anchor will be aligned to the wire.
-         \compat{Changed in 0.1.2}In addition to the normal paths implemented by \TikZ{} shapes, those fit for \Yquant{} must additionally implement clipping paths, a \Yquant{} addition to \TikZ{} shapes.
+         \compat{Changed in 0.1.2}In addition to the normal paths implemented by \TikZ{} shapes, the width and height of those fit for \Yquant{} at least twice as large as given by the \texttt{/tikz/x~radius} and \texttt{/tikz/y~radius}; and they must implement clipping paths, a \Yquant{} addition to \TikZ{} shapes.
          Such a path has to provide the ``clipping outline,'' i.e., anything that should not contain register or control lines.
          There may be a difference between horizontal and vertical clipping outlines.
          To understand clipping paths, \Yquant's drawing pipeline needs to be explained.
@@ -1102,7 +1122,7 @@ IndexSingle = ?number? | ( [ ?number? ], "-", [ ?number? ] );
                      Hence, the additional extent stemming from them should \emph{not} be equally distributed among all registers, but either to the height of the first or the depth of the last one.
                      Currently, \Yquant{} is unable to detect this (and, considering the fact that you can place \texttt{label}s at any angle, this is not an easy problem to solve except for special cases).
                   \item If you make use of a discontiguous \gate{init} gate with a large vertical extent, \Yquant{} will correctly allocate space as if the gate's content were placed in the vertical center.
-                     However, if there is no way to put the arch of the brace at the middle, as the register at this position is excluded from the gate, the content will be shifted---but only after calculating the extent.
+                     However, if there is no way to put the arch of the brace at the middle, as the register at this position is excluded from the gate, the content will be shifted---but only \emph{after} calculating the extent.
                      Hence, the automatically calculated vertical positions will be unsuitable.
                \end{itemize}
             \item Sometimes, there is more space available than \Yquant{} thinks because you already discarded some wire.
@@ -1130,6 +1150,7 @@ IndexSingle = ?number? | ( [ ?number? ], "-", [ ?number? ] );
       This section lists all operations \Yquant{} currently understands.
       It also details all arguments that can be given to customize the operation, apart from \texttt{name} and \compat{New in 0.4}\texttt{overlay}, which are always available.
       Note that the \tex![value=<value>]! attribute can (and should) alternatively be given as a braced expression that follows the name of the register.
+      Within \tex!<value>!, unless specified differently, the macro \tex!\idx! is always available and corresponds to the index of the current register in the list of targets.
 
       \subsection[\texorpdfstring{\yquant!addstyle!}{addstyle}]{\compat{New in 0.1.2}\yquant!addstyle!}\label{gate:addstyle}
          Syntax: \yquant!setstyle <target>;! \\
@@ -1182,6 +1203,7 @@ IndexSingle = ?number? | ( [ ?number? ], "-", [ ?number? ] );
          Syntax: \yquant!correlate <target>;! \\
          This is a pseudo\hyp gate that indicates a correlation (usually a Bell\hyp state) present between the multi\hyp registers involved.
          This gate should span multiple registers and does not allow for controls.
+         The style \style{/yquant/operators/every wave} is installed.
 
          \emph{Possible attributes:} none
 
@@ -1252,22 +1274,20 @@ IndexSingle = ?number? | ( [ ?number? ], "-", [ ?number? ] );
                The style \texttt{/yquant/every <type> label} is installed additionally.
             \item \yquant![value=<value>]! (required) \\
                Denotes the label that is printed to the left of the wire.
-
-               Inside the value, \tex!\idx! expands to the current index within the register list.
          \end{itemize}
 
       \subsection[\texorpdfstring{\yquant!inspect!}{inspect}]{\compat{New in 0.4}\yquant!inspect!}\label{gate:inspect}
          Syntax: \yquant!inspect <target>;! \\
          This is a pseudo\hyp gate that allows to print the current state of one or multiple registers within a circuit.
          It may span multiple registers, but does not allow for controls.
-         The style \style{/yquant/every inspect} is installed.
-         Essentially, it is the same as an \gate{output} gate that will be drawn immediately at the current position and not deferred until the end.
+         The style \style{/yquant/operators/every inspect} is installed.
+         Essentially, it is the same as an \gate{output} gate that will be drawn immediately at the current position and not deferred until the end; hence, it also draws braces when used in a multi\hyp register context.
+         \compat{New in 0.6}If this is not desired, use the \gate{text} gate instead.
 
          \emph{Possible attributes:}
          \begin{itemize}
             \item \yquant![value=<value>]! (required) \\
                Denotes the text that is to be printed.
-               Inside the value, \tex!\idx! expands to the current index within the register list.
          \end{itemize}
 
       \subsection[\texorpdfstring{\yquant!measure!}{measure}]{\compat{Changed in 0.4}\yquant!measure!}\label{gate:measure}
@@ -1320,12 +1340,12 @@ IndexSingle = ?number? | ( [ ?number? ], "-", [ ?number? ] );
          It may only be specified once per register.
          It may span multiple registers, but does not allow for controls.
          The style \style{/yquant/every output} is installed, and also the style \texttt{/yquant/every <type> output}, where \texttt{<type>} is the type of the affected register (at the time of printout).
+         \compat{New in 0.6}Note that while outputs can be named, the name will only become available after the \texttt{yquant} environment itself was ended (but of course before the outer \texttt{tikzpicture} was closed).
 
          \emph{Possible attributes:}
          \begin{itemize}
             \item \yquant![value=<value>]! (required) \\
                Denotes the text that is to be printed.
-               Inside the value, \tex!\idx! expands to the current index within the register list.
          \end{itemize}
 
       \subsection{\texorpdfstring{\yquant!phase!}{phase}}\label{gate:phase}
@@ -1411,12 +1431,15 @@ IndexSingle = ?number? | ( [ ?number? ], "-", [ ?number? ] );
 
          This gate is only available if a compatibility version before \texttt{0.4} is chosen.
 
-      \subsection{\texorpdfstring{\yquant!slash!}{slash}}\label{gate:slash}
+      \subsection[\texorpdfstring{\yquant!slash!}{slash}]{\compat{Changed in 0.4}\yquant!slash!}\label{gate:slash}
          Syntax: \yquant!slash <target>;! \\
          This is a pseudo\hyp gate used to denote that a single line actually represents multiple registers.
          It is drawn as a short slash through the line of the register.
-         Note that this gate, in contrast to all others, is positioned on the line extending from the last gate or the initialization line of the registers and does not advance the register's horizontal position.
          The style \style{/yquant/operators/every slash} is installed.
+         Note that this gate will ignore the \style{/yquant/operator/minimum width} key.
+         With a \texttt{compat} key of~0.3 or earlier, the gate was special in that it did not advance the horizontal position on the wire, which allows to use it on only some of the wires without leading to a ragged start of subsequent gates.
+         However, as \Yquant's default separation is not large enough to give a pleasant layout when the slash is squeezed in the initial separation, this was dropped as of version~0.4.
+         Use the \gate{align} gate after all \gate{slash}es to get a better layout.
 
          \emph{Possible attributes:} none
 
@@ -1468,6 +1491,20 @@ IndexSingle = ?number? | ( [ ?number? ], "-", [ ?number? ] );
 
          \emph{Possible attributes:} none
 
+      \subsection[\texorpdfstring{\yquant!text!}{text}]{\compat{New in 0.6}\yquant!text!}\label{gate:text}
+         Syntax: \yquant!text <targets> | <pcontrol> ~ <ncontrol>;! \\
+         This is a pseudo\hyp gate that allows to write some text within the circuit.
+         It may span multiple registers and allows for controls (though the situations in which controls make sense are pretty scarce).
+         The style \style{/yquant/operators/every text} is installed.
+         Contrary to the \gate{inspect} gate, this gate will not draw curly braces in multi\hyp register use.
+         It basically corresponds to a \gate{box} gate with suppressed drawing.
+
+         \emph{Possible attributes:}
+         \begin{itemize}
+            \item \yquant![value=<value>]! (required) \\
+               Denotes the text that is to be printed.
+         \end{itemize}
+
       \subsection{\texorpdfstring{\yquant!x!}{x}}\label{gate:x}
          Syntax: \yquant!x <target> | <pcontrol> ~ <ncontrol>;! \\
          This is a Pauli $\sigma_{\symup x}$ gate $\ketbra01 + \ketbra10$, denoted by a rectangle that contains the letter $X$.
@@ -1899,7 +1936,7 @@ qubit {$\ket{q_{\idx}} = \Ifcase\idx\relax \ket\psi \Else \ket0 \Fi$} q[3];
          \yquantset{operator/separation=2mm}
          For a better orientation, we use the same section headings as the \pkg{qcircuit} manual.
          The manual uses unnamed registers a lot; often, we will use the \tex!yquant*! environment to make things more concise.
-         As the \pkg{qcircuit} manual uses a bit larger separation between the operators than \Yquant's default, we globally say\\*\tex!\yquantset{operator/separation=1em}!.
+         As the \pkg{qcircuit} manual uses a bit larger separation between the operators than \Yquant's default, we globally say\\*\tex!\yquantset{operator/separation=2mm}!.
 
          \subsubsection{I. Introduction}
             \begin{example}<Updated in 0.5, 0.4, 0.1.1>%
@@ -2289,21 +2326,20 @@ qubit {$\ket{q_{\idx}} = \Ifcase\idx\relax \ket\psi \Else \ket0 \Fi$} q[3];
 
             \clearpage
             \paragraph{C. Non-gate inserts, forcing space, and swap}\leavevmode
-               \begin{example}<Updated in 0.1.1>
+               \begin{example}<Updated in 0.6, 0.1.1>
                   \begin{codeexample}
 \begin{tikzpicture}
    \begin{yquant*}
       [name=sw]
       swap (a[0-1]);
-      [draw=none]
-      box {$X$} a[1];
+      text {$X$} a[1];
       slash b;
       box {$H^{\otimes n}$} b;
       \node[anchor=199] at (sw-0.north) {Defective Circuit};
    \end{yquant*}
 \end{tikzpicture}
                   \end{codeexample}
-                  Here, the intermediate text was inserted by using a \gate{box} without drawing.
+                  Here, the intermediate text was inserted by using a \gate{text} gate; before version~0.6, this would have to be done by a \gate{box} gate with \yquant![draw=none]! attribute.
                   Another way would be to use an \gate{init} command, although this is semantically wrong (probably).
                \end{example}
 
@@ -2382,19 +2418,19 @@ qubit {$\ket{q_{\idx}} = \Ifcase\idx\relax \ket\psi \Else \ket0 \Fi$} q[3];
                \end{example}
 
             \paragraph{B. Labeling}\leavevmode
-               \begin{example}<Updated in 0.4>
+               \begin{example}<Updated in 0.6, 0.4>
                   \begin{codeexample}
 \begin{tikzpicture}
-   \begin{yquant}[every initial label/.style={anchor=south east, yshift=1mm}, every post measurement control=direct, operators/every box/.append style={draw=none}]
+   \begin{yquant}[every initial label/.style={anchor=south east, yshift=1mm}, every post measurement control=direct]
       qubit {\rlap{\hskip2mm $a$}} a;
       qubit {\rlap{\hskip2mm $b$}} b;
       nobit out;
       hspace {5mm} -;
 
       measure b;
-      box {$B$} out | b;
+      text {$B$} out | b;
       measure a;
-      box {$A$} out | a;
+      text {$A$} out | a;
       discard -;
    \end{yquant}
 \end{tikzpicture}
@@ -2402,10 +2438,10 @@ qubit {$\ket{q_{\idx}} = \Ifcase\idx\relax \ket\psi \Else \ket0 \Fi$} q[3];
                   We support measurements with vertical outputs, but only if they replace the positive control of some action.
                   Here, we fake this behavior by introducing an invisible register at the bottom, which will contain the outputs.
                   In order to disable the line around the \gate{box}es, we used the \style{/yquant/operators/every box} style, which here was most convenient, as the only \gate{box}es in use are those without an outline.
-                  However, if we instead want to say \texttt{[draw=none]} as an attribute to the \gate{box}es, this will also remove the outline of the measurements.
-                  The reason for this is that giving this as an attribute will in fact populate \style{/yquant/operator style}; and internally, the measurement will be nested within the same scope that draws the \gate{box}---so the options given to the \gate{box} will be inherited by the \gate{measure}ment.
+                  Note that if we were to give style options to the \gate{text}s, they would also affect the measurements.
+                  The reason for this is that internally, the measurement will be nested within the same scope that draws the \gate{text}---so the options given to the \gate{text} will be inherited by the \gate{measure}ment.
                   As an operator style overwrites default styles, this will also apply to the measurements.
-                  Hence, to circumvent this, we would have to additionally say \texttt{[draw]} as an attribute to the \gate{measure}ments, although this is already included in their native style.
+                  Hence, to circumvent this, we would need to \emph{revert} the options as attributes to the \gate{measure}ments, even if the reverted option was already included in their native style.
 
                   Repositioning the initial labels needs some care and manual fine\hyp tuning.
                \end{example}
@@ -2434,6 +2470,7 @@ qubit {$\ket{q_{\idx}} = \Ifcase\idx\relax \ket\psi \Else \ket0 \Fi$} q[3];
                   \end{codeexample*}
                   Note that \tex!\begin{yquant*}! must not be followed by a line break (unless masked by \tex!%!) if options follow.
                   Also note that here, we cannot make use of a subcircuit due to the very last control, which would then control an inner gate of said subcircuit---but they are not exposed.
+                  \iffalse\end{yquant*}\fi% code folding
                \end{example}
       \endgroup
 
@@ -2487,15 +2524,14 @@ qubit {$\ket{q_{\idx}} = \Ifcase\idx\relax \ket\psi \Else \ket0 \Fi$} q[3];
                \end{example}
 
             \paragraph{B. Wires and arrows}\leavevmode
-               \begin{example}<Updated in 0.1.2>
+               \begin{example}<Updated in 0.6, 0.1.2>
                   \begin{codeexample*}
 % \usetikzlibrary{quotes}
 \begin{tikzpicture}
    \begin{yquant}[operator/separation=1cm, every label/.append style={align=center}]
       qubit {$\ket0$\\initial state} a;
 
-      [draw=none]
-      box {$X$} a;
+      text {$X$} a;
 
       ["$0$/$1$", type=qubit]
       measure a;
@@ -3100,9 +3136,11 @@ $=$
    \end{yquant*}
 \end{tikzpicture}
                   \end{codeexample}
+                  Note that assigning styles in this way will forward them to \style{/yquant/operator style}, i.e., if you have controls, the style will not apply to them.
+                  \style{/yquant/style} is suitable to style both, e.g., \tex|[style={fill=red!20}]|.
                \end{example}
 
-               \begin{example}<Updated in 0.4>
+               \begin{example}<Updated in 0.6, 0.4>
                   \begin{codeexample*}
 % \usetikzlibrary{shapes.symbols, fit}
 \begin{tikzpicture}
@@ -3114,8 +3152,8 @@ $=$
       cnot anc1 | data;
       [after=data]
       qubit {$\ket0$} anc2[2];
-      [name=box, draw=none]
-      box {\phantom{noise}} (data, anc1);
+      [name=noise]
+      text {\phantom{noise}} (data, anc1);
       cnot anc2[0] | data;
       cnot anc2 | anc1[0];
       cnot anc2[1] | anc1[1];
@@ -3123,7 +3161,7 @@ $=$
       [blue] measure anc2[1];
    \end{yquant}
    \node[starburst, cyan, fill=yellow, draw=red, line width=2pt,
-         inner xsep=-4pt, inner ysep=-5pt, fit=(box)] {noise};
+         inner xsep=-4pt, inner ysep=-5pt, fit=(noise)] {noise};
 \end{tikzpicture}
                   \end{codeexample*}
                   \TikZ{} shapes cannot simply be used with \Yquant.
@@ -3206,7 +3244,7 @@ $=$
 
          \clearpage
          \subsubsection{VIII. Otherwise undocumented features}
-            \begin{example}<Updated in 0.4>
+            \begin{example}<Updated in 0.6, 0.4>
                \begin{codeexample*}
 % \usetikzlibrary{quantikz,fit}
 \begin{tikzpicture}
@@ -3219,8 +3257,7 @@ $=$
 
       h a, b;
       box {$U$} c | a;
-      [draw=none]
-      box {$\dots$} a, b-;
+      text {$\dots$} a, b-;
       box {$U^k$} c | b;
       h a, b;
    \end{yquant}
@@ -3254,158 +3291,1593 @@ $=$
             \end{example}
       \endgroup
 
-   \section{Foreign language support and extensions}\label{sec:foreign}
-      \Yquant{} is built in various modules, so that it is not hard to use the quantum circuit rendering backend, but expose a different language frontend.
-      \compat{New in 0.3}\Yquant{} not only understands its own language, but also others.
-      \compat{New in 0.5}Although we refer to ``foreign languages,'' additional extension packages of the \Yquant{} language itself are also covered in this section and can be loaded by the same syntax.
+      \subsection[\texorpdfstring{\pkg{qpic}}{qpic} documentation]{\compat{Added in 0.6}\pkg{qpic} documentation}
+      \begingroup
+         \yquantset{operator/separation=3mm, register/default name=$\reg$, register/default lazy name=$\reg$}%
+         Again, our section headings will be the same as in the \pkg{qpic} manual.
+         As the \pkg{qpic} manual uses a bit larger separation between the operators than \Yquant's default, we globally say \tex!\yquantset{operator/separation=3mm, register/default name=$\reg$, register/default lazy name=$\reg$}!, which allows to easily generate all the registers on\hyp the\hyp fly.
+
+         \subsubsection{1 Introduction}
+            \begingroup%
+               \mdfapptodefinestyle{bdBox}{%
+                  leftmargin=-.12\linewidth,
+                  rightmargin=-.12\linewidth
+               }%
+               \begin{example}\label{ex:qupicfirst}
+                  \begin{codeexample*}
+\def\reversecircuit#1{%
+   \begin{tikzpicture}
+      \let\high=\empty
+      \listeadd\high{#1}
+      \def\cnot##1|##2;{%
+         \ifinlist{##2}\high{
+            \yquant [style=red] cnot a[##1] | a[##2];
+            \ifinlist{##1}\high{
+               \listremove\high{##1}
+               \yquant addstyle {black} a[##1];
+            }{
+               \listadd\high{##1}
+               \yquant addstyle {red} a[##1];
+            }
+         }{
+            \yquant cnot a[##1] | a[##2];
+         }
+      }
+      \def\cnotA{\cnot 0|1; \cnot 2|3; \cnot 4|5; \cnot 6|7;}
+      \def\cnotB{\cnot 2|1; \cnot 4|3; \cnot 6|5; \cnot 8|7;}
+      \def\cnotC{\cnot 1|0; \cnot 3|2; \cnot 5|4; \cnot 7|6;}
+      \def\cnotD{\cnot 1|2; \cnot 3|4; \cnot 5|6; \cnot 7|8;}
+      \def\cnotBlock{\cnotA \cnotB barrier (-); \cnotC \cnotD}
+      \begin{yquant}[operator/minimum width=0pt, register/minimum height=2mm,
+                     register/minimum depth=2mm]
+         qubit {\Ifnum\idx=#1\color{red}\Fi$\reg_{\The\numexpr\idx+1}$} a[9];
+         addstyle {very thick, red} a[#1];
+
+         \cnotBlock barrier (-);
+         \cnotBlock barrier (-);
+         \cnotBlock barrier (-);
+         \cnotBlock barrier (-);
+         \cnotBlock
+         output {\protect\xifinlist{\idx}{\high}{\color{red}}\relax
+                 $a_{\The\numexpr9-\idx}$} -;
+      \end{yquant}
+   \end{tikzpicture}%
+}
+\reversecircuit2
+                  \end{codeexample*}
+                  This is an extremely interesting example, which could have been implemented in a lot of different manners.
+                  We chose an approach where we deferred the logic of coloring the gates entirely to \TeX.
+                  Note that we put everything, including the whole \texttt{tikzpicture} itself, in a macro \tex!\reversecircuit!, which we call directly after its definition by saying \tex!\reversecircuit2!.
+                  This is of course an overkill in this situation---there is no need for the macro definition.
+                  However, note that the macro expects the wire that is to be colored in red as its argument.
+                  So by slightly changing the invocation to
+                  \begin{minted}{tex}
+\foreach \ici in {0, ..., 8} {
+   \reversecircuit\ici
+   \par\vspace{1cm}
+}
+                  \end{minted}
+                  we are able to render the circuit with all different initial wires one after the other very easily.
+                  We do not show the output in the manual to keep it succinct, but just try it out by yourself.
+
+                  We now explain what is done in the macro.
+
+                  We first define an \pkg{etoolbox} list that is stored in \tex!\high!.
+                  The idea is that this list holds at any point in time the indices of all the registers that are currently colored in red.
+                  Initially, we add the index that was given as a parameter to the macro---in our case, this was \tex!2!.
+                  Note we use \tex!\listeadd! instead of \tex!\listadd!, which is important for the invocation via \tex!\foreach!---we want to have the number in the list, not the macro \tex!\ici! that holds the index of the initially colored wire).
+
+                  Next, we do not want to manually do the bookkeeping of this list.
+                  All we want to do is to issue the command to put a \gate{cnot} gate on the appropriate registers and \TeX{} should keep track of the correct coloring and register state.
+                  For this, we first define a macro \tex!\cnot! that expects the index of the target and the index of the control register.
+                  Within this macro, we check whether the register of the control is currently highlighted (\tex!\ifinlist{#2}\high!).
+                  If this is not the case, we draw the \gate{cnot} gate without any additional styles (note that since we interrupted the \Yquant{} parser due to the lots of intervening macros, we first have to restart it saying \tex!\yquant!).
+                  However, if it is the case that the control register is currently highlighted, we draw the \gate{cnot} gate with the attribute \texttt{[style=red]}---we do not only want to draw the gate itself in red (for which \texttt{[red]} would be sufficient), but also its control line and the control blob, so we use the \style{/yquant/style} shorthand.
+                  Note that in the \pkg{qpic} manual, some of the control lines are thicker than others.
+                  This could be implemented by adding the argument \tex!every control line/.append style={very thick}!; however, as it is unclear what the thick line should indicate, we did not add this to the example.
+
+                  Then, we have to change the state of the target register appropriately, since the highlighting state will propagate from control to target.
+                  If the target register was already highlighted, we have to remove it from the list and we change its line color back to \texttt{black}; if it was not highlighted, we add it to the list and change its line color to \texttt{red}.
+                  Note that the use of \gate{addstyle} will keep adding styles, so in the end, the register line style will be a long string \texttt{red,black,red,black,...}; we could do better by saying \gate{setstyle}, which would overwrite the line style.
+                  However, since we will initially set the line width of \tex!a[#1]! to \texttt{very thick}---which should be kept throughout the circuit---we would have to take additional care not to lose this setting.
+                  Here, we chose the simpler version.
+
+                  After setting the coloring preliminaries, we note that if we slice the circuit at any time, it will have four possible gate configurations (or a \gate{barrier}).
+                  We define abbreviations for these in the macros \tex!\cnotA! to \tex!\cnotD!.
+                  Since they will always follow in this order, we also define a \tex!\cnotBlock! abbreviation that executes these configurations together with their intermediate \gate{barrier}.
+                  We do not include the final barrier, since it is not present in the last block.
+
+                  Now, we start the \texttt{yquant} environment.
+                  We give some options for a nicer spacing and initialize the registers.
+                  In the \pkg{qpic} example, the registers are $1$\hyp indexed, so we use \tex!\The\numexpr\idx+1! to give back the value of the current register index (\tex!\idx!) plus one; we also conditionally color the register name in red if the index coincides with the parameter.
+                  Note that here we use \Yquant's shorthand for \tex!\protect\the!, \tex!\protect\ifnum!, and \tex!\protect\fi!, which are \tex!\The!, \tex!\Ifnum!, and \tex!\Fi!, to get the correct expansion behavior.
+
+                  Then, we add the initial style for the \tex!a[#1]! wire.
+                  Inserting the gates together with the correct coloring is now extremely simple: we just need to call our \tex!\cnotBlock! command and intersperse it with \gate{barrier}s.
+                  At the end, we output all the gates in reverse order, which works similarly to the initialization of the gates, and also conditionally color the reversed register.
+                  This coloring could in principle be done similarly to the coloring of the initial label, saying something like \tex!\Ifnum\numexpr8-\idx=#1 \color{red}\Fi!.
+                  Here, we chose the ``more honest'' approach to color all the registers that are still present in the coloring list---note the need to \tex!\protect! the \pkg{etoolbox} macro \tex!\xifinlist!.
+                  In this way, we could, e.g., terminate the circuit earlier and still get the correct output coloring at this particular point.
+
+                  Note that if there were more that just five blocks, we could also have made use of \TikZ's \tex!\foreach! loop to output all the \tex!\cnotBlock! commands.
+                  However, be aware of the fact that \tex!\foreach! puts its content in a group, so the \tex!\high! list assignments would have been local and forgotten in the next iteration.
+                  Either they would need to be made globally or some non\hyp grouping loop construct would have to be used (e.g., \tex!\pgfplotsforeachungrouped!).
+               \end{example}
+            \endgroup
 
-      \subsection[groups]{\compat{New in 0.5}groups}\label{sec:foreign:groups}
-         By saying \tex!\useyquantlanguage{groups}! in the preamble after loading \Yquant{} itself, additional support for groups of \Yquant{} circuits is loaded.
-         Various circuits in a group share a common set of registers, are appropriately aligned horizontally if on the same line and can also be aligned vertically among multiple lines.
-         The main intended use is for circuit equations.
+         \clearpage
+         \subsubsection{2 Simple Examples}
+            \paragraph{2.1 Example 1: Majority}\leavevmode
+               \begin{example}
+                  \begin{codeexample*}
+\begin{tikzpicture}
+   \begin{yquant*}
+      box {\rotatebox{90}{$\operatorname{MAJ}$}} (a, b, c);
 
-         This extension provides the environment \tex!yquantgroup!.
-         You may use this environment within a \tex!tikzpicture!; in this case, all page\hyp break related features are not available.
-         You may alternatively use the environment outside of a \tex!tikzpicture!; in this case, it will start and end the pictures appropriately.
+      text {$=$} (-);
 
-         As with \tex!yquant!, the environment accepts optional options that are passed to \tex!\yquantset!; a starred form is available that allows for the lazy creation of registers---but note that \emph{shared} registers must always be created explicitly; only if some circuits in the group have additional registers, the lazy creation applies.
+      cnot b | c;
+      cnot a | c;
+      cnot c | a, b;
 
-         \subsubsection{General usage}
-            \begin{minted}{tex}
-% preamble:
-% \usepackage[compat=<version>]{yquant}
-% \useyquantlanguage{groups}
-\begin{tikzpicture}% tikz options possible. This environment may be omitted.
-   % tikz commands go here
-   \begin{yquantgroup}% yquant(group) options possible.
-      \registers{
-         % arbitrary shared register declaration go here
-      }
-      % any of \circuit, \equals, \\, \shiftright
-      % if the tikzpicture environment was omitted: also allows
-      % \pagebreak, \newpage, \clearpage, \cleardoublepage
-      % in most cases, TikZ commands are also allowed
-   \end{yquantgroup}
-   % tikz commands go here
+      output {$a \oplus c$} a;
+      output {$b \oplus c$} b;
+      output {$\operatorname{MAJ}(a, b, c)$} c;
+   \end{yquant*}
 \end{tikzpicture}
-            \end{minted}
-
-         \subsubsection{Special macros}
-            \paragraph*{\tex!\registers!}
-               The \tex!\registers! macro can and must only be used once in a \tex!yquantgroup! environment.
-               It contains the declaration of all the registers that are shared among the various circuits within a group.
-               Basically, if you follow the convention in a usual \Yquant{} circuit to first declare all the registers, then use the gates, then you would put the declaration part in the \tex!\registers! macro.
-               However, note that it is in principle also possible to mix register declarations with other gates and \TikZ{} commands.
-
-               In case you do not use the \gate{import} gate in any of the circuits within the group and you do not declare own registers, the behavior is very straightforward: basically, the content of \tex!\registers! is copied verbatim at the beginning of each circuit.
-               Otherwise, the general rule is: importing a register will ensure that all non\hyp declaration commands that preceded this register declaration are executed; and importing the last register will additionally execute all succeeding commands within \tex!\registers!.
+                  \end{codeexample*}
+               \end{example}
 
-            \paragraph*{\tex!\circuit[<style>]{<content>}!}
-               The \tex!\circuit! macro can be thought of as starting a \tex!yquant! (or \tex!yquant*!) environment and using its mandatory argument \tex!<content>! as the content of the circuit; the optional \tex!<style>! is used to apply additional styling options to the circuit.
+            \clearpage
+            \paragraph{2.2 Example 2: Quantum Fourier Transform}\leavevmode
+               \begin{example}
+                  \begin{codeexample*}
+\begin{tikzpicture}
+   \begin{yquant}[operators/every box/.append style={shape=yquant-circle, radius=2.5mm}]
+      qubit {$x_2$} x2;
+      qubit {$x_1$} x1;
+      qubit {$x_0$} x0;
+
+      h x2;
+      box {$2$} x2 | x1;
+      box {$3$} x2 | x0;
+      h x1;
+      box {$2$} x1 | x0;
+      h x0;
+
+      output {$\frac{1}{\sqrt2} (\ket0 + e^{2\pi i \cdot 0.x_2 x_1 x_0}) \ket1$} x2;
+      output {$\frac{1}{\sqrt2} (\ket0 + e^{2\pi i \cdot 0.x_1 x_0}) \ket1$} x1;
+      output {$\frac{1}{\sqrt2} (\ket0 + e^{2\pi i \cdot 0.x_0}) \ket1$} x0;
+   \end{yquant}
+\end{tikzpicture}
+                  \end{codeexample*}
+                  In this example, we opted to use three distinct registers instead of one vector register, since the reversed indexing would probably have led to more confusion.
+                  We globally overwrite the \style{/yquant/operators/every box} style to use a circular shape instead.
+                  Note that this would usually be an ellipse, so we explicitly set the radius to a value that exceeds the minimum (half) width.
+                  As of version~0.6, the style \style{/yquant/operators/every box} is no longer the base style for other rectangular boxes such as \gate{h} (note this requires a compatibility version of at least \texttt{0.6} or higher).
+                  For earlier versions, the change in shape would also affect the Hadamard gate and therefore would have to be reverted using the \style{/yquant/operators/every h} style.
+               \end{example}
 
-               This is not entirely accurate: In reality, the content is put into a \gate{subcircuit} and \tex!<style>! is passed as arguments to the subcircuit.
+            \clearpage
+            \paragraph{2.3 Example 3: Shor's Algorithm}\leavevmode
+            \begingroup%
+               \mdfapptodefinestyle{bdBox}{%
+                  leftmargin=-.12\linewidth,
+                  rightmargin=-.12\linewidth
+               }%
+               \begin{example}
+                  \begin{codeexample*}
+\begin{tikzpicture}[rotate=-90, yscale=-1, every node/.append style={rotate=90, xscale=-1}]
+   \def\explain#1#2{%
+      \yquant
+      [anchor=east] text {#1} explainLeft;
+      [anchor=west] text {$\displaystyle#2$} explainRight;
+      align -;
+   }
+   \begin{yquant}[every initial label/.style={anchor=south},
+                  every output/.style={anchor=north},
+                  every control/.append style={radius=1.5mm},
+                  operators/every slash/.append style={x radius=3mm, y radius=1.5mm},
+                  operators/every box/.append style={y radius=4mm},
+                  operators/every measure/.append style={y radius=4mm},
+                  operator/minimum width=1.32cm]
+      nobit explainLeft;
+      qubit {$\ket{0\dotsm0}$} x; slash x;
+      qubit {$\ket{0\dotsm0}$} y; slash y;
+      nobit explainRight;
+      align -;
+
+      box {$H^{\otimes n}$} x;
+      \explain{Quantum Hadamard Transform}
+              {\sum_{x = 0}^{2^n -1} \ket x \ket 0}
+
+      box {$a^x \bmod N$} y | x;
+      \explain{Exponentiation}
+              {\sum_{x = 0}^{2^n -1} \ket x \ket{a^x \bmod N}}
+
+      measure y; output {$y$} y;
+      \explain{Measure $y = a^b$}
+              {\sum_{j = 0}^{\lfloor\frac{2^n -1}{r}\rfloor} \ket{b + j r} [y]}
+
+      box {QFT} x;
+      \explain{Quantum Fourier Transform}
+              {\sum_{x = 0}^{2^n -1} \left( \sum_{j = 0}^{\lfloor\frac{2^n -1}{r}\rfloor}
+                                            \omega^{x * (b + j r)} \right) \ket x}
+
+      output {$?$} x;
+   \end{yquant}
+\end{tikzpicture}
+                  \end{codeexample*}
+                  Once again, this is a very interesting example.
+                  \Yquant{} does not support a vertical circuit layout \emph{officially}.
+                  However, \Yquant{} is built on top of \TikZ, so we can certainly try to emulate a vertical layout by means of rotations.
+                  First of all, we rotate the whole \texttt{tikzpicture}, saying \tex!rotate=-90!, so that the circuit grows downwards.
+                  While this is very straightforward, it leads to two immediate problems:
+                  \begin{itemize}
+                     \item The registers were declared in top\hyp to\hyp bottom order; if we rotate everything, this becomes a right\hyp to\hyp left order.
+                        In order to change this to a left\hyp to\hyp right order, we must mirror every horizontal coordinate; due to the rotation, this corresponds to \tex!yscale=-1! (not \tex!xscale!).
+                     \item The gates themselves should not be rotated.
+                        In fact, no text should be rotated.
+                        However, as by default, the \style{/yquant/every circuit} style will install the \texttt{transform shape} option to every node as of version~0.4, the nodes will also be rotated.
+                        The first idea to disable \texttt{transform shape} does not turn out to work well, as the spacings are somehow messed up.
+                        Instead, we just undo the rotation and scaling (note that now we need \tex!xscale=-1!, as after the reverse rotation, we are back to the ``proper'' coordinate system).
+                  \end{itemize}
+                  Then, there are some minor issues regarding the anchors of initial labels and output.
+                  The default settings for them, \texttt{east} and \texttt{west} are of course inappropriate in a rotated layout, so those must be changed.
+                  All the rest of the options that are given to the \texttt{yquant} environment just serve to match the appearance given in the \pkg{qpic} manual: we enlarge the \gate{slash}, the \gate{box}es and the \gate{measure}ments, and we also increase the global value of \style{/yquant/operator/minimum width}.
+                  Remember that this is the minimum ``width'' (in the rotated scenario, it becomes a height) that \Yquant{} reserves for every single operator (unless it is larger), and it will center the operator within an invisible rectangle of this width if it is smaller.
+                  So by matching this value to the largest height that occurs in the explanations in the circuit, we achieve an approximate vertical centering.
 
-               The default style \style{/yquant/operators/every group circuit} is applied to the circuit.
-               This style is configured such that the illusion of working in a top\hyp level \tex!yquant! environment is very convincing: The circuit is frameless by default and uses the transparent name mangling scheme.
+                  Finally, there is some repetitive structure within the circuit, which we defer to a custom macro \tex!\explain!: We always want to draw a \gate{text} gate in our first invisible register \yquant!explainLeft!; however, this should not be centered, but rather aligned to the right, so we give the proper \tex!anchor=east!.
+                  We also need the same thing on the right, just mirrored and with a \tex!\displaystyle! math environment; and after all the explanations are done, we \gate{align} all registers (if the minimum width/height was chosen to be exactly larger or equal to the actual height of every gate, this would not be necessary; but with two decimals, this is probably not precisely the case).
 
-               All the registers that were previously defined via \tex!\registers! are automatically available within the circuit, as if their declaration had been copied.
-               In fact, \Yquant{} will make a register available the first time it is referenced in some gate; if at the end of a circuit some of the shared registers were not used, they will be imported before exiting the circuit.
-               Consequently, if you define own registers just for a single circuit, these will always be at the very top.
-               This can be influenced by means of the \gate{import} gate, which is only available in group \tex!\circuit!s.
-               This gate allows to import a declared register at an arbitrary position.
+                  Note that the code example above would work exactly in this way in traditional \LaTeX{} documents; however, this document is set with \pkg{unicode-math}.
+                  This leads to a problem when using \tex!\bmod!, which has to be \tex!\protect!ed---or, as we did here, just say \tex!\robustify\bmod! somewhere before its usage and after loading all the packages.
+               \end{example}
+            \endgroup
 
-            \paragraph*{\tex!\equals*[<content>]!}\label{sec:foreign:groups:equals}
-               The \tex!\equals! macro inserts a blank text---internally, a \gate{box}\hyp like gate with the style \style{/yquant/operators/every group equals}---that contains \tex!<content>!.
-               If omitted, \tex!<content>! is given by \tex!$=$!.
+            \clearpage
+            \paragraph{2.4 Example 4: Teleportation}
+               \begin{example}
+                  \begin{codeexample*}
+\begin{tikzpicture}[rotate=-90, yscale=-1, every node/.append style={rotate=90, xscale=-1}]
+   \begin{yquant}[every initial label/.style={anchor=south},
+                  every output/.style={anchor=north},
+                  operators/every barrier/.append style={rotate=-90}]
+      nobit explainLeft;
+      qubit {\color{red}$\ket\phi$} q;
+      qubit {$\ket0$} q[+2];
+      nobit explainRight;
+      setstyle {red} q[0];
 
-               The optional star will put a horizontal alignment mark at the position where the box is inserted.
-               Similar to the \tex!&! operation in \pkg{amsmath}'s \tex!align! environment or the \tex!\>! in \TeX's native \tex!tabbing!, \Yquant{} will now remember the horizontal position of the box internally and will allow you to directly jump to this position in the next line.
-               Note that you may well have multiple alignment marks in a single line, which \Yquant{} internally numbers \texttt{1}, \texttt{2}, \dots.
+      h q[1];
+      cnot q[2] | q[1];
+      setstyle {red} q[1];
+      setstyle {blue} q[2];
+      [y radius=5mm, anchor=west]
+      inspect {Alice and Bob form an\\entangled pair of qubits} (explainRight);
+      [operator/separation=0pt]
+      barrier (q);
+      align -;
+
+      [style=red, operator/separation=0pt] cnot q[1] | q[0];
+      [red] h q[0];
+      [red] measure q[0, 1];
+      [red, y radius=9mm, anchor=east, align=right, shape=yquant-init, decoration={mirror}]
+      inspect {Alice entangles\\and measures} (explainLeft);
+      align -;
+
+      [style=blue] x q[2] | q[1];
+      [style=blue] z q[2] | q[0];
+      discard q[0, 1];
+      [blue, y radius=5.5mm, anchor=west]
+      inspect {Bob applies gates based on\\Alice's measurements} (explainRight);
+
+      output {\color{blue}$\ket\phi$} q[2];
+   \end{yquant}
+\end{tikzpicture}
+                  \end{codeexample*}
+                  Again, we ignore that it is not possible to render the circuit in this way and do it anyway.
+                  The structure is similar to what we previously did.
+                  For some reason, the \gate{barrier} shape is not content with the back\hyp rotation and we must again rotate it.
 
-            \paragraph*{\tex!\\[<separation>]!}
-               The \tex!\\! macro inserts a line break (never a page break), so that the next \tex!\circuit! or \tex!\equals! will be put below all circuits that were output before, and it will again start at the same left position as the first circuit.
-               The default vertical distance is given by \style{/yquant/group/line separation}, but it may be overwritten by the optional \tex!<separation>! argument, which must be a \TeX{} dimension.
+                  We now use \gate{inspect} gates to mimic the state information.
+                  This gate will automatically draw curly braces as soon as it encounters a multi\hyp register use; hence, despite the fact that \yquant!explainRight! and \yquant!explainLeft! are single registers, we use them in a multi\hyp register fashion.
+                  Next, the brace would only be high enough to incorporate the text (since it knows nothing about what goes on in the rest of the circuit); hence, we manually give it a \texttt{y radius} value that has to be determined appropriately.
 
-               Note that if you \emph{set} new alignment marks in a new line, this will delete the alignment marks that were previously set.
+                  Since the default operator separation before and after the \gate{barrier} look a bit large, we set them to zero (\style{/yquant/operator/separation} will always affect the distance of the current operator to the previous one, so we need this for the \gate{barrier} and for the first \gate{cnot} gate after the \gate{barrier}).
 
-               If the option \style{/yquant/group/aligned} is passed to the \tex!yquantgroup! environment, the command \tex!\shiftright! is implied after each linebreak.
+                  The \gate{inspect} gate on the left\hyp hand side needs some special attention.
+                  In a horizontal layout, the brace will of course always be drawn left to the text, as the \gate{inspect} gate is supposed to denote the current state of the registers.
+                  Therefore, we need to mirror the brace itself (\tex!decoration={mirror}!), and we also need to put it to the right\hyp hand side.
+                  Coincidentally, the \texttt{yquant-init} style has the brace at its right\hyp hand side, so we just choose to change the style.
+                  Using the \gate{init} gate instead would directly have invoked the correct \texttt{shape}; however, semantically, it is wrong, it would have changed the wire type to something visible (requiring a \gate{discard} directly afterwards) and it is also not scalable via \texttt{y radius}.
+               \end{example}
 
-            \paragraph*{\tex!\shiftright*[<where>]!}
-               The \tex!\shiftright! command will put the ``cursor,'' i.e., the horizontal position at which the next \tex!\circuit! or \tex!\equals! will start, at the position specified by \tex!<where>!.
-               By default, \tex!<where>! is \tex!1!.
-               If the optional star is present, \Yquant{} will additionally put an alignment mark at this position (see the documentation for \hyperref[sec:foreign:groups:equals]{\tex!\equals!}).
-               If the option \style{/yquant/group/aligned} is passed to the \tex!yquantgroup! environment, the command \tex!\shiftright! is implied after each linebreak or starred page break.
+         \subsubsection{3.1 Wires}
+            \paragraph{3.1.1 Wire Declarations}
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant}
+      qubit a;
+      qubit b;
+      qubit {} c;
 
-               The option \tex!<where>! can take various forms:
-               \begin{itemize}
-                  \item It may be a natural number \texttt{1}, \texttt{2}, \dots, denoting the number of an alignment mark specified in a previous line.
-                  \item It may be the number \texttt{0}, denoting the very beginning of the line; this is useful if the \style{/yquant/group/aligned} option is given, but for a specific line, no alignment should be performed.
-                  \item It may be a \TeX{} dimension, in which case this dimension is directly added to the cursor (so it is a relative value).
-                     This is where passing the optional star makes most sense.
-                     If you want to position absolutely, you may first issue \tex!\shiftright[0]! followed by a shift by the dimension that you want.
-               \end{itemize}
+      hspace {1cm} -;
 
-               \begin{warning}
-                  The macro is named \tex!\shiftright!; however, \Yquant{} does not enforce that the actual position is to the right of the current position.
-                  You may indeed be able to create overlapping circuits if you shift back to a previous position.
-               \end{warning}
+      output {$\phi$} a;
+   \end{yquant}
+\end{tikzpicture}
+                  \end{codeexample}
+               \end{example}
 
-            \paragraph*{\tex!\pagebreak*!, \tex!\newpage*!, \tex!\clearpage*!, \tex!\cleardoublepage*!}
-               The page breaking commands are available only if the \tex!yquantgroup! was not enclosed in a \tex!tikzpicture!.
-               They will end the current picture environment, issue the original page breaking command, and start a new picture.
-               Hence, if you want to pass options globally to the picture, you should use the \style{/yquant/preamble} option for the \tex!yquantgroup!; the content of this key will be passed as options for every implicitly started \tex!tikzpicture!.
+               \begin{example}
+                  \begin{codeexample}
+\makeatletter
+% https://tex.stackexchange.com/a/112212/32357
+\DeclareRobustCommand\rvdots{%
+   \vbox{%
+      \baselineskip4\p@\lineskiplimit\z@%
+      \kern-\p@%
+      \hbox{.}\hbox{.}\hbox{.}%
+   }%
+}
+\begin{tikzpicture}
+   \begin{yquant}[every nobit output/.style={}, register/separation=3mm]
+      qubit {$x_1$} x;
+      qubit {$\rvdots$} x[+1]; discard x[1];
+      qubit {$x_n$} x[+1];
 
-               Usually, remembering the horizontal alignment marks on a new page does not make much sense.
-               For this reason, the commands will delete all alignment; use their starred versions to retain them.
-               If the option \style{/yquant/group/aligned} is passed to the \tex!yquantgroup! environment, the command \tex!\shiftright! is implied after the starred version of the page break.
+      hspace {1cm} -;
 
-               Typically, you will not want to refer to named gates in a circuit on a different page; remember that if you need this feature, you must pass the \texttt{remember picture} key in the \style{/yquant/preamble} option, as this is a reference to another \tex!tikzpicture!.
-               Also don't forget to use the (\TikZ) \texttt{overlay} key on the corresponding path that references the node in order not to mess up with the bounding box (see the \TikZ{} documentation for those two keys).
+      output {$y_1$} x[0];
+      output {$\rvdots$} x[1];
+      output {$y_n$} x[2];
+   \end{yquant}
+\end{tikzpicture}
+                  \end{codeexample}
+                  This is one of at least four possible implementations (note we \href{https://tex.stackexchange.com/a/112212/32357}{defined \tex!\rvdots!}, since the native \tex!\vdots! does not appear to be very well\hyp centered).
+                  It declares the ``invisible'' register as part of the vector register \yquant!x!.
+                  As a consequence, whenever the whole vector register is addressed in operations, the operation is also drawn on the invisible register.
+                  For multi\hyp register gates, this may be desired (they just span the whole region), for single\hyp register gates, this is most certainly undesired.
+                  Note that \Yquant{} does not allow to declare an \gate{output} gate for invisible registers---usually, this does not make sense.
+                  However, this is not enforced as a hard constraint, but rather due to the fact that the style \style{/yquant/every nobit output} does not exist.
+                  To prevent an error message, we just define this as an empty style.
+                  Also note that, to get a proper vertical spacing, we decided to use the \style{/yquant/register/separation} key---which works well, as there are no other registers.
+                  If there were others, it would be better to increase the height and depth of the invisible register.
+
+                  Alternatively, we might declare the invisible register with a completely different name.
+                  This would create a discontiguous vector register \yquant!x!, which is probably the better thing to do for single\hyp register gates.
+                  However, \Yquant{} may now try to split multi\hyp register gates into contiguous slices---there could be arbitrary registers between discontiguous parts of a vector register, and they should of course not be targeted if they are not in the list of targets of a gate---but here, we would actually want to have this.
+
+                  A third approach mixes \Yquant{} and \TikZ{} code.
+                  We declare a vector register with size two, manually increase, say, the depth of the first register, and put a \tex!\node! at the appropriate position by naming the initial labels.
+                  In this way, vector usage will never target the ``invisible'' line---since it does not exist; both single\hyp{} and multi\hyp register gates will work appropriately.
+                  As a drawback, we need to decide whether we want to enlarge the depth of the first or the height of the second register (or both, splitting in half)---but what if some gates will actually be so large that they would provide enough of height or depth had we just chosen a different way of distribution the space?
+
+                  In order to remediate this, a fourth way using only two registers would be to defer the drawing of the dots to a multi\hyp register \gate{text} gate which receives a \texttt{y~radius} that enforces an appropriate separation.
+                  \Yquant{} will then automatically perfectly distribute the vertical extents among height and depth of the involved registers.
+                  The drawback with this approach is of course that the dots will be drawn \emph{within} the circuit, not to the left.
+                  There is an undocumented option that we can use to shift the gate to the left; but since this only works for initializers, we still need to draw the dots for the outputs manually.
+                  A possible implementation could look as follows.
+
+                  \begingroup%
+                     \makeatletter%
+                     \DeclareRobustCommand\rvdots{%
+                        \vbox{%
+                           \baselineskip4\p@\lineskiplimit\z@%
+                           \kern-\p@%
+                           \hbox{.}\hbox{.}\hbox{.}%
+                        }%
+                     }%
+                     \begin{codeexample}
+% \rvdots definition from above
+\begin{tikzpicture}
+   \begin{yquant}
+      qubit {$x_1$} x;
+      qubit {$x_n$} x[+1];
+      [internal/move label, anchor=east, y radius=8mm]
+      text {$\rvdots$} (x);
 
-            \subsubsection{Configuration}
-               Loading the \pkg{groups} language extension will define several new configuration keys.
+      hspace {1cm} -;
 
-               \begin{option}{group/every group}!!
-                  Style that is installed for every \tex!yquantgroup! and \tex!yquantgroup*! environment, as if it had been given as an option.
-                  The style's default path is \texttt{/tikz}.
-               \end{option}
+      [name=o1]
+      output {$y_1$} x[0];
+      [name=o2]
+      output {$y_n$} x[1];
+   \end{yquant}
+   \path (o1.south west) -- (o2.north west) node[midway, /yquant/every output] {$\rvdots$};
+\end{tikzpicture}
+                     \end{codeexample}
+                  \endgroup%
+               \end{example}
 
-               \begin{option}{group/line separation}!5mm!
-                  This is the default vertical line separation that is inserted whenever a new line is issued in a \tex!yquantgroup!.
-               \end{option}
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}
+      [decorate=false, draw=none]
+      init {$A$} (q[0, 1]);
+      init {$\ket0^{\otimes3}$} (q[2-4]);
 
-               \begin{option}{group/aligned}!false!
-                  This boolean flag defines whether \tex!\shiftright! is automatically issued after \tex!\\! and the starred page breaking commands.
-               \end{option}
+      hspace {1cm} -;
 
-               \begin{option}{preamble}!!
-                  This style may only be passed to the \tex!yquantgroup! alignment directly as an option; it is not available via \tex!\yquantset! and the like.
-                  It is only relevant if the \tex!yquantgroup! is not contained in a \tex!tikzpicture!.
-                  The content of this style will be given as an optional argument to the \tex!tikzpicture!; this is the recommended way to specify \TikZ{} options, as they are automatically preserved among page breaks.
-               \end{option}
+      output {$B$} (q[1, 2]);
+      output {$\ket0^{\otimes2}$} (q[3, 4]);
+   \end{yquant*}
+\end{tikzpicture}
+                  \end{codeexample}
+                  Note that here the $A$ is drawn without the curly braces.
+                  There are two simple ways to achieve this: by setting \texttt{draw} to \texttt{none}, the curly brace is suppressed, but still the~$A$ would be drawn at the same position as if the brace were there.
+                  We additionally set \texttt{decorate} to \texttt{false} to fully remove any reminiscence of the brace, so that the text is closest to the wires.
+                  (Note that just removing the decoration without also removing the drawing would lead to a vertical line that connects all the affected wires---this is how the \texttt{yquant-init} shape looks like in an undecorated fashion.)
+               \end{example}
 
-               \begin{option}{operators/every group circuit}!/yquant/operators/every subcircuit, /yquant/operators/subcircuit/frameless, /yquant/operators/subcircuit/name mangling=transparent!
-                  This style is installed for the \gate{subcircuit} that implicitly wraps each \tex!\circuit!.
-                  Note that some magic is carried out to ensure that the name mangling setting only applies to the \emph{direct} content of the \tex!\circuit!; any \gate{subcircuit}s within the \tex!\circuit! will use the default name mangling scheme.
-               \end{option}
+         \subsubsection{3.2 Gates}
+            \paragraph{3.2.1 Controlled NOT and controlled $Z$}
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}
+      not a;
+   \end{yquant*}
+\end{tikzpicture}
+                  \end{codeexample}
+               \end{example}
 
-               \begin{option}{operators/every group equals}!shape=yquant-rectangle, align=center, inner xsep=1mm, x radius=2mm, y radius=2.47mm!
-                  This style is installed for every \tex!\equals!, which is internally realized similarly to a \gate{box} gate.
-               \end{option}
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}[register/default lazy name=$\symbol{\numexpr`a+\idx}$]
+      cnot q[1] | q[0];
+   \end{yquant*}
+\end{tikzpicture}
+                  \end{codeexample}
+                  Since in \Yquant's notation, \texttt{b} is mentioned before \texttt{a}, it would also be created as the first wire.
+                  If we instead resort to vector registers, we can directly specify which position our registers should have.
+                  Of course, for longer circuits, an explicit declaration is probably favorable.
+               \end{example}
 
-            \subsubsection{Gates and operations}
-               No gates or operations may be used directly within the \tex!yquantgroup! environment, but all the usual \Yquant{} gates and operations are available within \tex!\registers! and \tex!\circuit!.
-               Additionally, within \tex!\circuit!, the \gate{import} gate is available.
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}[register/default lazy name=$\symbol{\numexpr`a+\idx}$]
+      cnot q[2] | q[-1];
+   \end{yquant*}
+\end{tikzpicture}
+                  \end{codeexample}
+               \end{example}
 
-               \paragraph*{\yquant!import!}\label{gate:import}\leavevmode\\
-                  Syntax: \yquant!import <target>;! \\
-                  This is a pseudo\hyp gate that makes all the outer registers given in \tex!<target>! available in the current circuit.
-                  Consequently, the register names that are specified in \tex!<target>!, also ranges, do not refer to the registers in the \emph{current} \tex!\circuit!, but instead to those defined via \tex!\registers!.
-                  Therefore, it is for example possible to import all outer registers at once using \yquant!import -;!.
-                  Vector registers can also be imported partially.
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}
+      not a;
+      zz (b, c);
+      cnot c | a ~ b;
+   \end{yquant*}
+\end{tikzpicture}
+                  \end{codeexample}
+               \end{example}
 
-                  If additional content (\TeX{} commands such as \TikZ{} paths, non\hyp creation gates) is used within \tex!\registers!, everything that comes \emph{before} the declaration of a register will be copied into the \tex!\circuit! when the register is imported; for a vector, this refers to the index zero.
-                  Additionally, any additional content that comes \emph{after} the declaration of the last register will be copied directly after the last register was imported.
+            \paragraph{3.2.2 General Gates}
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}
+      box {\symbol{\numexpr`A+\idx}} a, b;
+      box {$\tau$} (-);
+      box {GATE} a | b;
+   \end{yquant*}
+\end{tikzpicture}
+                  \end{codeexample}
+                  Note that the macro \tex!\idx! is available in any gate, and it gives the index of the current register within the target list.
+               \end{example}
+
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}[operators/every box/.append style={shape=yquant-circle}]
+      box {$\rho$} a;
+      box {$\rho$} b | a;
+      box {$\rho$} (-);
+   \end{yquant*}
+\end{tikzpicture}
+                  \end{codeexample}
+                  Note that the macro \tex!\idx! is available in any gate, and it gives the index of the current register within the target list.
+               \end{example}
+
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}[rotate=-90]
+   \begin{yquant*}[every initial label/.style={anchor=east}]
+      box {\rotatebox{90}{$M$}} (c, b) | a;
+      box {\rotatebox{90}{GATE}} (-);
+      box {\rotatebox{90}{$M^{-1}$}} (c, b) | a;
+   \end{yquant*}
+\end{tikzpicture}
+                  \end{codeexample}
+                  Remember that \Yquant{} doesn't really support vertical layout, so it is always a bit of an experiment to make this work.
+                  Multi\hyp register gates don't work too well when trying to apply the back\hyp rotation trick of before.
+               \end{example}
+
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}
+      [name=fs] box {\Ifnum\idx<1 $f^{-1}$\Else $f$\Fi} (a, b), (c, d);
+      [name=g] box {$g$} (b, c) | a;
+      [shape=yquant-circle, name=theta] box {$\theta$} d;
+   \end{yquant*}
+   \draw (fs-0) -- (fs-1) (g) -- (theta);
+\end{tikzpicture}
+                  \end{codeexample}
+                  By putting the two $f$\hyp boxes into a single gate, we ensured that \Yquant{} will center them with respect to each other.
+               \end{example}
+
+            \clearpage
+            \paragraph{3.2.3 Other predefined Gates}
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}
+      h a;
+      h x;
+   \end{yquant*}
+\end{tikzpicture}
+                  \end{codeexample}
+               \end{example}
+
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}
+      z a, b;
+      zz (-);
+      z a | b;
+   \end{yquant*}
+\end{tikzpicture}
+                  \end{codeexample}
+               \end{example}
+
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}
+      zz (a, b), (c, d);
+      zz (b, c);
+      zz (-b), (c-);
+      zz (b, c);
+   \end{yquant*}
+\end{tikzpicture}
+                  \end{codeexample}
+               \end{example}
+
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}
+      swap (a, b);
+   \end{yquant*}
+\end{tikzpicture}
+                  \end{codeexample}
+               \end{example}
+
+               \begin{example}
+                  \begin{codeexample*}
+\begin{tikzpicture}
+   \begin{yquant*}[plusctrl/.style={/yquant/every control/.style={/yquant/operators/every not}, /yquant/every positive control/.style={}}]
+      [plusctrl] box {$f$} (a, b) | c;
+      [plusctrl, shape=yquant-circle] box {$\zeta$} c | d;
+      [plusctrl] box {$f$} (a, b) | c;
+      cnot b | a;
+      cnot c | d;
+   \end{yquant*}
+\end{tikzpicture}
+                  \end{codeexample*}
+                  This very unorthodox\hyp looking style can be achieved by altering the control styles in such a way that it basically looks like a \gate{not} gate.
+               \end{example}
+
+         \subsubsection{3.3 Attributes}
+            \paragraph{Size Attributes}
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}
+      [y radius=20pt] box {HIGH} (a, b);
+      [x radius=20pt] box {WIDE} (-);
+   \end{yquant*}
+\end{tikzpicture}
+                  \end{codeexample}
+                  Note that \texttt{LONG} and \texttt{BROAD} do not make sense, as \Yquant{} does not support vertical layout.
+               \end{example}
+
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}[rotate=-90, yscale=-1, every node/.append style={yscale=-1}]
+   \begin{yquant*}[every initial label/.style={rotate=45, anchor=east, shift={(.15, .15)}}]
+      [x radius=20pt]
+      box {\rotatebox{90}{HIGH}} (a, b);
+      [y radius=20pt]
+      box {\rotatebox{90}{WIDE}} (a, b);
+   \end{yquant*}
+\end{tikzpicture}
+                  \end{codeexample}
+                  Again, trying to properly adjust the position of the initial labels is more trial\hyp and\hyp error than anything else, and very fragile with respect to changes in the circuit.
+               \end{example}
+
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant}
+      [register/minimum depth=10pt]
+      qubit a;
+      qubit b;
+      [register/minimum height=1pt]
+      qubit c;
+
+      cnot c | a, b;
+   \end{yquant}
+\end{tikzpicture}
+                  \end{codeexample}
+                  Upon creation, the minimum register sizes can be passed on to \Yquant; note that the \style{/yquant/register/minimum height} extends from the wire line to the top of the space that is allocated for the wire, whereas the corresponding key \style{/yquant/register/minimum depth} extends from the wire line to the bottom.
+                  Hence, the values given here are half of \pkg{qpic}'s.
+               \end{example}
+
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}
+      [inner sep=0pt, radius=2.5pt]
+      box {} a | b;
+      [shape=yquant-circle, radius=10pt]
+      box {$g$} b | a;
+      cnot a | b;
+      [operator style={radius=7.5pt}, control style={radius=4pt}]
+      cnot a | b;
+   \end{yquant*}
+\end{tikzpicture}
+                  \end{codeexample}
+                  To mimick closely \pkg{qpic}'s manual, we used an empty \gate{box} instead of the \gate{xx} gate, which also is a rectangle.
+                  Note that the shapes that accept text also have an inner separation, which would interfere with the \texttt{radius} setting.
+               \end{example}
+
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}
+      [x radius=12.5pt]
+      box {$f$} a;
+      [radius=12.pt, shape=yquant-circle]
+      box {$f$} a;
+   \end{yquant*}
+\end{tikzpicture}
+                  \end{codeexample}
+                  Note that when changing to the \texttt{yquant-circle} shape, this will become an ellipse if only one of the radii is modified.
+               \end{example}
+
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant}
+      qubit {\color{purple}$a$} a;
+      setstyle {purple} a;
+      qubit b;
+
+      [style=green!50!black]
+      cnot a | b;
+      setstyle {red} b;
+      [orange, control style=blue]
+      h a | b;
+   \end{yquant}
+\end{tikzpicture}
+                  \end{codeexample}
+               \end{example}
+
+               \begin{example}
+                  \begin{codeexample}
+\yquantdefinebox{circle}[shape=yquant-circle, draw, inner sep=0pt, radius=2mm]{}
+\begin{tikzpicture}
+   \begin{yquant*}
+      [fill=red!50!white] box {$f$} a | b;
+      [fill=blue, name=b] circle a;
+      [fill=green, name=g] circle b;
+      not a;
+      [fill=yellow] not b;
+   \end{yquant*}
+   \draw (b) -- (g);
+\end{tikzpicture}
+                  \end{codeexample}
+               \end{example}
+
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}
+      setstyle {dotted} a;
+      setstyle {very thick} b;
+      [dashed, fill=yellow] box {$G$} (-);
+      cnot a | b;
+      setstyle {densely dotted} a;
+   \end{yquant*}
+\end{tikzpicture}
+                  \end{codeexample}
+               \end{example}
+
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}[on/.style={red, very thick}]
+   \begin{yquant*}[on/.style={style=red, control style={very thick}}]
+      cnot a | b;
+      qubit {\color{red}$c$} c;
+      setstyle {on} c;
+      [on] cnot b | c;
+      setstyle {on} b;
+      [on] cnot a | b;
+      setstyle {on} a;
+   \end{yquant*}
+\end{tikzpicture}
+                  \end{codeexample}
+                  This example demonstrates for the first time that new registers can also be declared at any later time in the circuit.
+                  Note that we defined two very different styles:
+                  \begin{itemize}
+                     \item \texttt{/tikz/on} for the \texttt{tikzpicture} \\
+                        This is an ordinary \TikZ{} style and hence will be applied whenever it is used in a styling context---for example, when added to the wire styles.
+                     \item \texttt{/yquant/on} for the \texttt{yquant*} environment \\
+                        This is a style that does not directly apply any styling, but it instead passes options to \style{/yquant/style} (we want to have the gates as well as their controls and control lines in red) as well as to \style{/yquant/control style} (we want to draw the control lines thicker [in principle, this would also affect the controls, but they are filled, not drawn], but we don't want to draw the lines of the \gate{cnot} gates themselves be drawn thicker.).
+                        Since attributes for gates will first look in the \texttt{/yquant} namespace, this style is applied when used as an attribute for a gate (but beware that \yquant![style=on]! would call the other style).
+                  \end{itemize}
+               \end{example}
+
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant}[register/default name=$\reg$]
+      cbit a;
+      qubit b;
+      h b | a;
+      discard a;
+   \end{yquant}
+\end{tikzpicture}
+                  \end{codeexample}
+               \end{example}
+
+               \Yquant{} does not offer the variety of shapes that \pkg{qpic} does; please file a feature request if there is a need.
+
+               \begin{example}
+                  \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant}
+      qubit a;
+      qubit b;
+      [shape=yquant-circle, radius=1.2mm, inner sep=0pt]
+      box {$\cdot$} b | a;
+      box {$A$} (-);
+   \end{yquant}
+\end{tikzpicture}
+                  \end{codeexample}
+               \end{example}
+
+               \clearpage
+               \begin{example}
+                  \begin{codeexample*}
+% \usepackage[hidelinks]{hyperref}
+% \usetikzlibrary{calc}
+\makeatletter
+\def\tikzHyperNode#1{%
+   \ifdefined\tikz@alias%
+      \unless\ifyquantmeasuring%
+         \pgfqkeysalso{/tikz}{%
+            % https://tex.stackexchange.com/a/36111/32357
+            alias=sourcenode,
+            append after command={
+               % we don't need to worry about outer sep, yquant shapes ignore this value
+               let \p1=(sourcenode.north west),
+                   \p2=(sourcenode.south east),
+                   \n1={\x2-\x1},
+                   \n2={\y1-\y2} in
+               node [inner sep=0pt, outer sep=0pt, anchor=north west, at=(\p1)]
+               {#1{\XeTeXLinkBox{\phantom{\rule{\n1}{\n2}}}}}
+            }%
+         }%
+      \fi%
+   \fi%
+}
+\tikzset{
+   hyperlink/.code={\tikzHyperNode{\hyperlink{#1}}},
+   hyperref/.code={\tikzHyperNode{\hyperref[{#1}]}}
+}
+
+\begin{tikzpicture}
+   \begin{yquant}
+      qubit a;
+      qubit b;
+      [hyperref=sec:grammar]
+      box {SUB} (a-b);
+   \end{yquant}
+\end{tikzpicture}
+                  \end{codeexample*}
+                  In principle, adding a hyperlink to any gate works as adding a hyperlink to any \TikZ{} node.
+                  We use a standard implementation; because of the way \Yquant{} internally handles styles applied to a gate, we must protect this in the \tex!\ifdefined\tikz@alias! (\Yquant{} executes the options outside of nodes first to set, e.g., line styles appropriately, which leads to an error, as the \texttt{alias} option only works within nodes).
+                  We also want to refrain from unnecessarily adding hyperlinks during the initial measurement phase.
+                  We then provide two \TikZ{} styles to do the job, depending on whether the link should be created via \tex!\hyperlink! or \tex!\hyperref! and apply it.
+                  Note that here, we explicitly created the registers first.
+                  Had we used an implicit creation, we would also have applied to hyperref to the register labels!
+
+                  Be aware of the fact that hyperlinks in PDFs will always be rectangular; if your gate shape is different from this, do not expect the shapes to match.
+               \end{example}
+
+         \subsubsection{3.4 Measurement and Other Wire Type Changes}
+            \begin{example}
+               \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}
+      measure a;
+      cnot b | a;
+      dmeter {$Z$} b;
+   \end{yquant*}
+\end{tikzpicture}
+               \end{codeexample}
+            \end{example}
+
+            \Yquant{} does not support the \texttt{tag} shape.
+
+            \begin{example}
+               \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}
+      [direct control] measure a;
+      cnot b | a;
+      dmeter {$Z$} b;
+   \end{yquant*}
+\end{tikzpicture}
+               \end{codeexample}
+            \end{example}
+
+            \begin{example}
+               \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}[operator/separation=2mm]
+      setstyle {-|, shorten >= 3mm} a;
+      inspect {$0$} a;
+      discard a;
+
+      hspace {1cm} -;
+
+      setstyle {|-, shorten <= 2mm} a;
+      init {$1$} a;
+   \end{yquant*}
+\end{tikzpicture}
+               \end{codeexample}
+               There are no gates in \Yquant{} that resemble the visual \gate{discard} or reinitialization marker; however, this can be achieved by placing appropriate arrowheads at the wires.
+               Still, this is a problematic solution: Every wire in \Yquant{} will extend from the center of one gate to the center of the next gate; protruding parts will be clipped away.
+               Hence, the arrowhead will not be visible, as it is below the \gate{inspect} or \gate{init} gate---so we must \texttt{shorten} the wire by an ``appropriate'' amount.
+               Additionally, if the circuit were longer, we would want to quickly get rid of this arrowhead style.
+               \Yquant{} will try to make the wire lines as long as possible---i.e., in a normal circuit without any changes, the wire will in fact be one continuous line from the left to the right.
+               However, whenever something changes at the wire---say, the style or type is changed---\Yquant{} needs to start a new path.
+               We don't want the arrowheads to still be installed on this new path, hence we would quickly need to remove them.
+            \end{example}
+
+            \begin{example}
+               \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant}
+      qubit a;
+      hspace {5mm} a;
+      [after=a] qubit b;
+      box {$f$} (a, b);
+      inspect {$A$} a;
+      [after=a] qubit c;
+      discard a;
+      box {$g$} (b, c);
+      align -;
+      init {$a'$} a;
+      inspect {$B$} b;
+      discard b;
+      box {$h$} (-);
+      output {$A'$} a;
+      output {$C'$} c;
+   \end{yquant}
+\end{tikzpicture}
+               \end{codeexample}
+               Here, we create registers with the \texttt{after} attribute at some later point in the circuit.
+               Note that logically speaking, the $h$~box should have had the targets \yquant!(a, c)!; however, as \Yquant{} does not know that the middle register was already discarded, it would have drawn two boxes joined by a wiggly line to indicate the discontiguous multi\hyp qubit register.
+            \end{example}
+
+         \subsubsection{3.5 Managing Slices}
+            \begin{example}
+               \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant}
+      qubit a; qubit b; qubit c; qubit d;
+      zz (a, c);
+      h b;
+      measure d;
+   \end{yquant}
+\end{tikzpicture}
+               \end{codeexample}
+            \end{example}
+
+            \begin{example}
+               \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant}
+      qubit a; qubit b; qubit c; qubit d;
+      zz (a, c);
+      h b;
+      align -;
+      measure d;
+   \end{yquant}
+\end{tikzpicture}
+               \end{codeexample}
+            \end{example}
+
+            \begin{example}
+               \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant}
+      qubit a; qubit b; qubit c; qubit d;
+      zz (a, c);
+      align -;
+      h b;
+      measure d;
+   \end{yquant}
+\end{tikzpicture}
+               \end{codeexample}
+            \end{example}
+
+            \begin{example}
+               \begin{codeexample*}
+\begin{tikzpicture}
+   \begin{yquant}[operators/every barrier/.style={shape=yquant-line, draw, shorten <= -2mm, shorten >= -2mm, decoration={zigzag, segment length=4, amplitude=1pt}, decorate}]
+      qubit a; qubit b; qubit c; qubit d;
+      zz (a, c);
+      h b;
+      align -;
+      barrier d;
+      measure d;
+      [red] barrier a, d;
+   \end{yquant}
+\end{tikzpicture}
+               \end{codeexample*}
+               Note that a \Yquant{} \gate{barrier} works a bit differently from \pkg{qpic}'s.
+               It is basically just an ordinary gate with a dashed line style; by the fact that all registers that are listed in the target list are aligned automatically, the \gate{barrier} usually does its job.
+               Hence, we need to \gate{align} before the first \gate{barrier}, as it does not perform an alignment by itself on registers that were not mentioned as targets.
+
+               Here, we also change the default style (which is a dashed line) to the zigzag line that uses \pkg{qpic}'s style.
+               Note that \Yquant{} automatically loads the library \texttt{decorations.pathmorphing}, so we don't need to do this.
+            \end{example}
+
+            \begin{example}
+               \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}[operator/minimum width=0pt, operator/separation=2mm]
+      [shape=yquant-circle, radius=1.5ex]
+      box {$2$} a | b;
+      h a, b, c;
+      [style=green!50!black]
+      cnot c | a, b;
+      [operator/separation=0pt, green!50!black]
+      not c;
+   \end{yquant*}
+\end{tikzpicture}
+               \end{codeexample}
+               In order to stick two operators directly next to each other, we must set the \style{/yquant/operator/separation} to zero; this is the whitespace that is inserted before an operator.
+               However, if the total with of an operator is smaller than \style{/yquant/operator/minimum width}, it is centered in a box of this width (giving a more uniform layout with lots of small gates), which would add additional whitespace both to the right of the Hadamards and to the left of the \gate{cnot}s.
+               We just globally suppress this minimum width, which is unproblematic for this particular circuit (we could also locally change it).
+            \end{example}
+
+            \begin{example}
+               \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}[operator/minimum width=0pt, operator/separation=2mm]
+      [shape=yquant-circle, radius=1.5ex]
+      box {$2$} a | b;
+      h a, b, c;
+      [style=red]
+      cnot c | a, b;
+      [operator/separation=0pt]
+      not c;
+      cnot c | a, b;
+      [operator/separation=0pt, red]
+      not c;
+   \end{yquant*}
+\end{tikzpicture}
+               \end{codeexample}
+            \end{example}
+
+            \begin{example}
+               \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}[operators/every box/.append style={shape=yquant-circle, radius=1.5ex}]
+      box {$1$} a;
+      not b;
+      box {$2$} a;
+      align -;
+      not b;
+   \end{yquant*}
+\end{tikzpicture}
+               \end{codeexample}
+               An instruction like \texttt{MIXGATES} does not exist in \Yquant, as it does not use a grid\hyp based layout; but of course, its behavior can be faked by \gate{align} gates.
+            \end{example}
+
+         \clearpage
+         \subsubsection{3.6 Reversing and Repeating}
+            \begin{example}
+               \begin{codeexample*}
+\begin{tikzpicture}
+   \yquantdefinegate{cnots}{
+      qubit a; qubit b; qubit c;
+      cnot b | a;
+      cnot b | c;
+      cnot a | b;
+      cnot c | b;
+   }
+   \begin{yquant*}
+      cnots (a, b, c);
+      cnots (-);
+   \end{yquant*}
+\end{tikzpicture}
+               \end{codeexample*}
+               \Yquant{} does not have a concept of slices and hence can also not automatically repeat gates within a certain slice.
+               However, there are multiple ways to achieve the circuits in this section without repeating parts manually.
+               Here, we defined a custom gate that contained the content and inserted it two times.
+               Another alternative would be to do this using macros, as was illustrated in the \hyperref[ex:qupicfirst]{very first example} of the \pkg{qpic} section.
+            \end{example}
+
+            \begin{example}
+               \begin{codeexample*}
+\begin{tikzpicture}
+   \yquantdefinegate{gates}{
+      qubit a; qubit b; qubit c;
+      [plusctrl] box {$f$} a | b;
+      addstyle {dotted} b;
+      [plusctrl] box {$g$} (a, b) | c;
+      [plusctrl] box {$f$} a | b;
+      addstyle {solid} b;
+   }
+   \begin{yquant*}[plusctrl/.style={/yquant/every control/.style={/yquant/operators/every not}, /yquant/every positive control/.style={}}]
+      gates (a, b, c);
+      cnot b | c;
+      gates (-);
+   \end{yquant*}
+\end{tikzpicture}
+               \end{codeexample*}
+               Note that for this sequence, we did basically the same thing as before, as we identified a symmetric slice---so reversing the order does not do anything.
+
+               We will also expand this example and give a very simple (and a bit shortsighted) implementation of a macro that reverses the order of gates.
+               Note that this macro basically just splits its content at semicolons and when it is done inputs all the parts in reverse order.
+               Hence, it will fail if semicolons appear, e.g., in attributes without enclosing them in braces.
+               It also does not correspond exactly to the \texttt{R} instruction from \pkg{qpic}, as it does not \emph{reverse} wire styles (basically \gate{addstyle} would become a hypothetical \gate{subtractstyle} macro), but just inserts them in reverse order.
+               Hence, the following example will give a different circuit with respect to the wire style!
+
+               \begin{codeexample*}
+\makeatletter
+\long\def\reversegates#1{%
+   \begingroup%
+      \let\reversegates@list=\empty%
+      \count0=0 %
+      \expandafter\reversegates@i#1;\reversegates@stop%
+}
+\long\def\reversegates@i#1;#2\reversegates@stop{%
+   \ifstrempty{#2}{%
+      \yquant@fordown \reversegates@idx := \count0 downto 1 {%
+         \expandafter\expandafter\expandafter\yquant%
+            \csname reversegates@list@\reversegates@idx\endcsname%
+      }%
+      \endgroup%
+   }{%
+      \ifstrequal{#2}{;}{%
+         \reversegates@i;\reversegates@stop%
+      }{%
+         \advance\count0 by 1 %
+         \csdef{reversegates@list@\the\count0}{#1;}%
+         \reversegates@i#2\reversegates@stop%
+      }%
+   }
+}
+\begin{tikzpicture}
+   \def\gates{%
+      [plusctrl] box {$f$} a | b;
+      addstyle {dotted} b;
+      [plusctrl] box {$g$} (a, b) | c;
+      [plusctrl] box {$f$} a | b;
+      addstyle {solid} b;
+   }
+   \begin{yquant*}[plusctrl/.style={/yquant/every control/.style={/yquant/operators/every not}, /yquant/every positive control/.style={}}]
+      \expandafter\yquant\gates
+      cnot b | c;
+      \reversegates\gates
+   \end{yquant*}
+\end{tikzpicture}
+               \end{codeexample*}
+            \end{example}
+
+            \begin{example}
+               \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant}
+      qubit a; qubit b; qubit c;
+      cnot b | a;
+      cnot b | c;
+      \foreach \i in {1, 2} { \yquant
+         cnot a | b;
+         cnot c | b;
+      }
+   \end{yquant}
+\end{tikzpicture}
+               \end{codeexample}
+               Another way to repeat things is to just use appropriate repetition macros (and remember to restart the parser); here, we used \tex!\foreach! from \TikZ, but any other will also do the job.
+            \end{example}
+
+         \subsubsection{3.7 Other Circuit Elements}
+            \begin{example}
+               \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}[operators/every slash/.append style={radius=2mm}]
+      slash a;
+      [label=10:n] slash a;
+   \end{yquant*}
+\end{tikzpicture}
+               \end{codeexample}
+            \end{example}
+
+            \begin{example}
+               \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant}
+      qubit a; qubit b;
+      cnot b | a;
+      inspect {\Ifcase\idx$a$\Else$a \oplus b$\Fi} -;
+      cnot b | a;
+      inspect {$b$} b;
+   \end{yquant}
+\end{tikzpicture}
+               \end{codeexample}
+               Here, we achieved the centering of the two \gate{inspect}ed registers by putting them in a single gate instruction with case discrimination.
+            \end{example}
+
+            \begin{example}
+               \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}
+      swap (a, b);
+      text {$=$} (-);
+      cnot b | a;
+      cnot a | b;
+      cnot b | a;
+   \end{yquant*}
+\end{tikzpicture}
+               \end{codeexample}
+               This is a very simple equality; for more complicated ones, the \hyperref[sec:foreign:groups]{\texttt{groups}} library is recommended.
+            \end{example}
+
+            \begin{example}
+               \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant}
+      qubit a; qubit b; qubit c; qubit d;
+      box {$f$} (a, b);
+      inspect {$G$} (a, b);
+      init {$F$} (c, d);
+      box {$g$} (c, d);
+   \end{yquant}
+\end{tikzpicture}
+               \end{codeexample}
+               Note that we first defined all the registers explicitly, and they all use an initializing text.
+               Had we directly used the \gate{init} gate on the registers \yquant!(c, d)! as the \emph{first} gate when \emph{neither} of both registers had an initializing text, then the~$F$ would have been placed to the left of the wires.
+               Basically, a \gate{qubit} declaration with a value is the same as declaring the register without a value plus another \gate{init} gate that puts the value in place.
+               A zero\hyp length \gate{hspace} gate or an \gate{align}ment directly at the beginning would be a way to prevent this shift to the left from happening.
+            \end{example}
+
+            \Yquant{} does not support the permutation gate that \pkg{qpic} has.
+            It would however not be very difficult to implement this particular shape and make it available.
+            Maybe even a multi\hyp swap gate using the \texttt{knots} library would be possible.
+
+         \clearpage
+         \subsubsection{3.8 Comments}
+            \begin{example}
+               \begin{codeexample*}
+\begin{tikzpicture}
+   \begin{yquant}
+      qubit a; qubit b;
+      \foreach \i in {0, 1, 2} { \yquant
+         cnot b | a;
+         cnot a | b;
+         \ifnum\i<2 \yquant
+            [operator/separation=2pt, operator/minimum width=0pt]
+            barrier (-);
+         \fi
+      }
+   \end{yquant}
+\end{tikzpicture}
+               \end{codeexample*}
+            \end{example}
+
+            \begin{example}
+               \begin{codeexample}
+% \usetikzlibrary{quotes}
+\begin{tikzpicture}
+   \begin{yquant}[operators/every box/.append style={shape=yquant-circle, radius=1.5ex}]
+      qubit a;
+      [blue, "above" above] box {$1$} a;
+      [red, "below" below] box {$2$} a;
+      ["both" above, "sides" below] box {$3$} a;
+   \end{yquant}
+\end{tikzpicture}
+               \end{codeexample}
+            \end{example}
+
+            \begin{example}
+               \begin{codeexample*}
+% \usetikzlibrary{calc}
+\begin{tikzpicture}
+   \begin{yquant}[operators/every box/.append style={shape=yquant-circle, radius=1.5ex}]
+      qubit a;
+      [name=1] box {$1$} a;
+      [name=2] box {$2$} a;
+      [name=3] box {$3$} a;
+   \end{yquant}
+   \draw[decoration=brace, decorate]
+      ($(1.north west)+(-.1,.1)$) -- ($(2.north east)+(.1,.1)$)
+      node[midway, above=1pt] {above};
+   \draw[blue, decoration={brace, mirror}, decorate]
+      ($(2.south west)+(-.1,-.1)$) -- ($(3.south east)+(.1,-.1)$)
+      node[midway, below=1pt] {below};
+\end{tikzpicture}
+               \end{codeexample*}
+            \end{example}
+
+            \begin{example}
+               \begin{codeexample*}
+\begin{tikzpicture}
+   \begin{yquant*}
+      [this subcircuit box style={draw=none, fill=red!40!white}]
+      subcircuit {
+         qubit {} a; qubit {} b;
+         cnot b | a;
+         cnot a | b;
+      } (a, b);
+      [this subcircuit box style={draw, dotted, rounded corners=10pt}]
+      subcircuit {
+         qubit {} a; qubit {} b;
+         cnot b | a;
+         cnot a | b;
+      } (b, c);
+   \end{yquant*}
+\end{tikzpicture}
+               \end{codeexample*}
+            \end{example}
+
+         \clearpage
+         \subsubsection{3.9 Macros and \LaTeX{} Code}
+            \begin{example}
+               \begin{codeexample}
+\begin{tikzpicture}[loud/.style={red, very thick}]
+   \yquantdefinebox{phase2}[loud, draw, shape=yquant-circle, radius=1.5ex]{$2$}
+   \begin{yquant*}
+      [style=loud]
+      phase2 a | b;
+      phase2 b;
+   \end{yquant*}
+\end{tikzpicture}
+               \end{codeexample}
+               Note that here, we choose an alternative gate name, as there already is the built\hyp in gate \gate{phase}.
+               While we could overwrite it, this is generally a very bad idea.
+               Keep in mind that gate declarations are global and also that gates are case insensitive, so changing the capitalization would not help.
+               Finally note that when we define a style for a new gate, it only pertains to the \emph{gate} itself.
+               It is not possible to change styles external to the gate---such as control lines---within the gate definition itself.
+            \end{example}
+
+            \begin{example}
+               The following example in the \pkg{qpic} manual requires some additional thoughts.
+               It defines a custom gate with a variable number of target registers.
+               The \tex!\yquantdefinegate! interface does not officially allow for this, although some low\hyp level hacking can of course be done (a \emph{sorted} \pkg{etoolbox} list is provided in the macro \tex!\yquant@circuit@subcircuit@param!, which holds the internal indices of all currently involved target registers).
+
+               It is of course always possible to write some macros that output the required gate commands.
+               Looking at the particular example, it is actually not really necessary to define a gate that has a variable number of targets.
+               Rather, in \Yquant, one would define a new gate that just contains the two $\oplus$ symbols next to each other; the control line is drawn separately from the gate anyway.
+               This very straightforward description will unfortunately fail, for the following reason:
+               When a control line is drawn, \Yquant{} currently always draws it from the \texttt{center} anchor of the current shape upwards or downwards.
+               However, for the $\mathord\oplus\!\mathord\oplus$ shape, the control line point should actually be in the middle of the right $\oplus$.
+               This is an off\hyp center point, so we need some hacking to convince \Yquant{} to do this.
+               The following code is pretty long; we will therefore give parts of the code, followed by an explanation.
+
+               First of all, we define a shape (similar to what is done in \texttt{yquant-shapes.tex}) that holds the two $\oplus$es.
+               \begin{codeexample*}
+\makeatletter
+\pgfdeclareshape{yquant-doubleoplus}{%
+   \inheritsavedanchors[from=yquant-slash]%
+   \anchor{center}{\pgfqpoint{.5\dimexpr\xradius\relax}{0pt}}%
+   \foreach \anc in {north, east, south, west} {
+      \inheritanchor[from=yquant-rectangle]{\anc}
+   }
+   \anchor{north east}{\pgfqpoint{.853553\dimexpr\xradius\relax}
+                                 {.707107\dimexpr\yradius\relax}}%
+   \anchor{south east}{\pgfqpoint{.853553\dimexpr\xradius\relax}
+                                 {-.707107\dimexpr\yradius\relax}}%
+   \anchor{south west}{\pgfqpoint{-.853553\dimexpr\xradius\relax}
+                                 {-.707107\dimexpr\yradius\relax}}%
+   \anchor{north west}{\pgfqpoint{-.853553\dimexpr\xradius\relax}
+                                 {.707107\dimexpr\yradius\relax}}%
+   % The border anchor is a bit more tricky, we leave it out here
+   \backgroundpath{%
+      \pgf@relevantforpicturesizefalse%
+         \pgfpathmoveto{\pgfqpoint{-.5\dimexpr\xradius\relax}{\yradius}}%
+         \pgfpathlineto{\pgfqpoint{-.5\dimexpr\xradius\relax}{-\yradius}}%
+         \pgfpathmoveto{\pgfqpoint{.5\dimexpr\xradius\relax}{\yradius}}%
+         \pgfpathlineto{\pgfqpoint{.5\dimexpr\xradius\relax}{-\yradius}}%
+         \pgfpathmoveto{\pgfqpoint{-\xradius}{0pt}}%
+         \pgfpathlineto{\pgfqpoint{\xradius}{0pt}}%
+         \pgfpathellipse{\pgfqpoint{-.5\dimexpr\xradius\relax}{0pt}}%
+                        {\pgfqpoint{.5\dimexpr\xradius\relax}{0pt}}%
+                        {\pgfqpoint{0pt}{\yradius}}%
+      \pgf@relevantforpicturesizetrue%
+      \pgfpathellipse{\pgfqpoint{.5\dimexpr\xradius\relax}{0pt}}%
+                     {\pgfqpoint{.5\dimexpr\xradius\relax}{0pt}}%
+                     {\pgfqpoint{0pt}{\yradius}}%
+   }%
+   \clippath{%
+      \pgfpathellipse
+         {\pgfqpoint{-.5\dimexpr\xradius}{0pt}}
+         {\pgfqpoint{.5\dimexpr\xradius+\pgflinewidth}{0pt}}
+         {\pgfqpoint{0pt}{\dimexpr\yradius+.5\pgflinewidth\relax}}%
+      \pgfpathellipse
+         {\pgfqpoint{.5\dimexpr\xradius\relax}{0pt}}
+         {\pgfqpoint{.5\dimexpr\xradius+\pgflinewidth\relax}{0pt}}
+         {\pgfqpoint{0pt}{\dimexpr\yradius+.5\pgflinewidth\relax}}%
+   }%
+}
+               \end{codeexample*}
+               \input \minted@jobname.pyg % we need to execute all this again without the group
+               Nothing special happens in the first few lines (although the \texttt{center} anchor is now off\hyp center): We declare a new shape \texttt{yquant-doubleoplus}, inherit some saved anchors and anchors (for details, see the \TikZ{} manual, section~106.5.3, ``Command for Declaring New Shapes'').
+               The \texttt{x~radius} now corresponds to the \emph{diameter} of one of the circles, since we have two circles next to each other.
+               We do not define border anchors at the moment; they would require some additional computation, but in lots of scenarios, they are not necessary (as we would also not need most of the anchors, but it is always good to have them).
+               The clip path is also not very special, it just contains the shape that is to be clipped away; basically, both circles.
+               The background path deserves more attention.
+               We draw the two circles and the vertical and horizontal lines; but note that we disable the \pkg{pgf}'s size protocol for all but the right circle.
+               Hence, when this shape is used, \TeX{} and \Yquant{} will actually think that it only occupies space for the right circle; the left one will protrude in the margin.
+               (Actually, we could wrap this in a test such as \tex!\ifdefined\yquant@prefix! to only discard protocoling within a \texttt{yquant} environment, so that the shape is properly usable outside.)
+
+               Next, we must take care of re\hyp inserting this ``lost'' margin whenever the gate is used; and we also define a style that appropriately uses the shape:
+               \begin{codeexample*}
+\yquantset{
+   operators/every noffoli/.style={
+      shape=yquant-doubleoplus, x radius=2.6mm, y radius=1.3mm, draw
+   },
+   internal/noffoli shift/.code={%
+      \begingroup%
+         \expandafter\tikzset\expandafter{\yquant@draw@@style}%
+         \tikzset{/yquant/every operator, /yquant/operators/every noffoli, /yquant/this operator}%
+         \edef\cmd{%
+            \endgroup
+            \dimdef\noexpand\yquant@config@operator@sep{%
+               \yquant@config@operator@sep+
+               \pgfkeysvalueof{/tikz/x radius}%
+            }%
+         }%
+         \cmd
+   }
+}
+               \end{codeexample*}
+               \input \minted@jobname.pyg % we need to execute all this again without the group
+               The first style is almost a copy of the \style{/yquant/operators/every not} style, only with the new shape and a doubled \texttt{x~radius}.
+               The second style is more complicated: Protected in a group, it first sets all the custom style overwrites that a user may pass to the gate (e.g., the user may wish to overwrite the radii)---those are stored in the internal macro \tex!\yquant@draw@@style!.
+               Then, it applies the styles in the order as the gate would do it; note that an attribute such as \yquant![x radius=1cm]! would only add the directive to the \style{/yquant/this operator} style, but not apply it yet, therefore we now execute all the options that were stored previously.
+               As the final action that survives the group, we add the current value for the \texttt{x~radius} to the current value of the operator separation---this effectively enacts the proper placement of our gate.
+
+               Having defined those styles, we finally need to declare the gate itself, so that it can be used in a circuit:
+               \begin{codeexample*}
+\yquant@langhelper@declare@command
+   {noffoli}
+   {}
+   {%
+      \appto\yquant@attrs@remaining{,/yquant/internal/noffoli shift}%
+      \yquant@prepare
+         {}%
+         {/yquant/operators/every noffoli}%
+   }%
+\yquant@langhelper@setup@attrs{noffoli}{}{}
+               \end{codeexample*}
+               % those were global commands anyway
+               We call \tex!\yquant@langhelper@declare@command!, as for every standard gate declaration, with the desired name of the gate (\tex!{noffoli}!), the actions that are to be carried out \emph{before} the targets and controls are parsed (\tex!{}!), and the actions that are to be carried out once the targets and controls are known.
+               We append the style that we just defined to the list of attributes, and execute the gate preparation.
+               Finally, we also declare the attributes that this gate takes---no required and no optional attributes.
+
+               After all this work, which can be saved in some shared document and used whenever necessary, we can come to the application, which is now very straightforward.
+
+               \begin{codeexample}
+\begin{tikzpicture}
+   \begin{yquant*}
+      noffoli a | b, c;
+      [style=red] noffoli c | a, b;
+      noffoli b | a;
+   \end{yquant*}
+\end{tikzpicture}
+               \end{codeexample}
+            \end{example}
+
+            \begin{example}
+               \begin{codeexample}
+% \usetikzlibrary{backgrounds}
+\begin{tikzpicture}
+   \begin{yquant}
+      qubit a; qubit b;
+      [name=cn]
+      cnot b | a;
+      \draw[fill=blue] (cn) circle[radius=5pt];
+      box {FONT} (-);
+      [name=cn, fill=boxBlueBody]
+      cnot b | a;
+      \scoped[on background layer] \draw[fill=red] (cn) circle[radius=5pt];
+   \end{yquant}
+\end{tikzpicture}
+               \end{codeexample}
+               There are no special options to mix \TikZ{} code with \Yquant{} code, as this can be done natively at any time.
+               To draw at the position of another gate, just name the gate.
+               Note that---as was illustrated here---also using the same name multiple times is possible, in this case, the latter use overwrites the former.
+               There is no direct equivalent to the \texttt{PRETIKZ} option---the gate has to be drawn first in order to get its position.
+               However, \TikZ{} supports layers, so it is easy to draw something behind a gate: just put it on a background layer, e.g., the one provided by the \texttt{backgrounds} library.
+               Also note that here, we filled the second \gate{cnot} gate with our background color in order to give the same image as in the \pkg{qpic} manual.
+               The circle is not filled by default, hence the red ``outer'' circle would be visible also inside the \gate{cnot} circle.
+            \end{example}
+
+            The \texttt{HYPERTARGET} instruction can be directly reproduced in \TeX{} by just putting a \tex!\hypertarget! before the \texttt{tikzpicture}.
+      \endgroup
+
+   \section{Foreign language support and extensions}\label{sec:foreign}
+      \Yquant{} is built in various modules, so that it is not hard to use the quantum circuit rendering backend, but expose a different language frontend.
+      \compat{New in 0.3}\Yquant{} not only understands its own language, but also others.
+      \compat{New in 0.5}Although we refer to ``foreign languages,'' additional extension packages of the \Yquant{} language itself are also covered in this section and can be loaded by the same syntax.
+
+      \subsection[groups]{\compat{New in 0.5}groups}\label{sec:foreign:groups}
+         By saying \tex!\useyquantlanguage{groups}! in the preamble after loading \Yquant{} itself, additional support for groups of \Yquant{} circuits is loaded.
+         Various circuits in a group share a common set of registers, are appropriately aligned horizontally if on the same line and can also be aligned vertically among multiple lines.
+         The main intended use is for circuit equations.
+
+         This extension provides the environment \tex!yquantgroup!.
+         You may use this environment within a \tex!tikzpicture!; in this case, all page\hyp break related features are not available.
+         You may alternatively use the environment outside of a \tex!tikzpicture!; in this case, it will start and end the pictures appropriately.
+
+         As with \tex!yquant!, the environment accepts optional options that are passed to \tex!\yquantset!; a starred form is available that allows for the lazy creation of registers---but note that \emph{shared} registers must always be created explicitly; only if some circuits in the group have additional registers, the lazy creation applies.
+
+         \subsubsection{General usage}
+            \begin{minted}{tex}
+% preamble:
+% \usepackage[compat=<version>]{yquant}
+% \useyquantlanguage{groups}
+\begin{tikzpicture}% tikz options possible. This environment may be omitted.
+   % tikz commands go here
+   \begin{yquantgroup}% yquant(group) options possible.
+      \registers{
+         % arbitrary shared register declaration go here
+      }
+      % any of \circuit, \equals, \\, \shiftright
+      % if the tikzpicture environment was omitted: also allows
+      % \pagebreak, \newpage, \clearpage, \cleardoublepage
+      % in most cases, TikZ commands are also allowed
+   \end{yquantgroup}
+   % tikz commands go here
+\end{tikzpicture}
+            \end{minted}
+
+         \subsubsection{Special macros}
+            \paragraph*{\tex!\registers!}
+               The \tex!\registers! macro can and must only be used once in a \tex!yquantgroup! environment.
+               It contains the declaration of all the registers that are shared among the various circuits within a group.
+               Basically, if you follow the convention in a usual \Yquant{} circuit to first declare all the registers, then use the gates, then you would put the declaration part in the \tex!\registers! macro.
+               However, note that it is in principle also possible to mix register declarations with other gates and \TikZ{} commands.
+
+               In case you do not use the \gate{import} gate in any of the circuits within the group and you do not declare own registers, the behavior is very straightforward: basically, the content of \tex!\registers! is copied verbatim at the beginning of each circuit.
+               Otherwise, the general rule is: importing a register will ensure that all non\hyp declaration commands that preceded this register declaration are executed; and importing the last register will additionally execute all succeeding commands within \tex!\registers!.
+
+            \paragraph*{\tex!\circuit[<style>]{<content>}!}
+               The \tex!\circuit! macro can be thought of as starting a \tex!yquant! (or \tex!yquant*!) environment and using its mandatory argument \tex!<content>! as the content of the circuit; the optional \tex!<style>! is used to apply additional styling options to the circuit.
+
+               This is not entirely accurate: In reality, the content is put into a \gate{subcircuit} and \tex!<style>! is passed as arguments to the subcircuit.
+
+               The default style \style{/yquant/operators/every group circuit} is applied to the circuit.
+               This style is configured such that the illusion of working in a top\hyp level \tex!yquant! environment is very convincing: The circuit is frameless by default and uses the transparent name mangling scheme.
+
+               All the registers that were previously defined via \tex!\registers! are automatically available within the circuit, as if their declaration had been copied.
+               In fact, \Yquant{} will make a register available the first time it is referenced in some gate; if at the end of a circuit some of the shared registers were not used, they will be imported before exiting the circuit.
+               Consequently, if you define own registers just for a single circuit, these will always be at the very top.
+               This can be influenced by means of the \gate{import} gate, which is only available in group \tex!\circuit!s.
+               This gate allows to import a declared register at an arbitrary position.
+
+            \paragraph*{\tex!\equals*[<content>]!}\label{sec:foreign:groups:equals}
+               The \tex!\equals! macro inserts a blank text---internally, a \gate{box}\hyp like gate with the style \style{/yquant/operators/every group equals}---that contains \tex!<content>!.
+               If omitted, \tex!<content>! is given by \tex!$=$!.
+
+               The optional star will put a horizontal alignment mark at the position where the box is inserted.
+               Similar to the \tex!&! operation in \pkg{amsmath}'s \tex!align! environment or the \tex!\>! in \TeX's native \tex!tabbing!, \Yquant{} will now remember the horizontal position of the box internally and will allow you to directly jump to this position in the next line.
+               Note that you may well have multiple alignment marks in a single line, which \Yquant{} internally numbers \texttt{1}, \texttt{2}, \dots.
+
+            \paragraph*{\tex!\\[<separation>]!}
+               The \tex!\\! macro inserts a line break (never a page break), so that the next \tex!\circuit! or \tex!\equals! will be put below all circuits that were output before, and it will again start at the same left position as the first circuit.
+               The default vertical distance is given by \style{/yquant/group/line separation}, but it may be overwritten by the optional \tex!<separation>! argument, which must be a \TeX{} dimension.
+
+               Note that if you \emph{set} new alignment marks in a new line, this will delete the alignment marks that were previously set.
+
+               If the option \style{/yquant/group/aligned} is passed to the \tex!yquantgroup! environment, the command \tex!\shiftright! is implied after each linebreak.
+
+            \paragraph*{\tex!\shiftright*[<where>]!}
+               The \tex!\shiftright! command will put the ``cursor,'' i.e., the horizontal position at which the next \tex!\circuit! or \tex!\equals! will start, at the position specified by \tex!<where>!.
+               By default, \tex!<where>! is \tex!1!.
+               If the optional star is present, \Yquant{} will additionally put an alignment mark at this position (see the documentation for \hyperref[sec:foreign:groups:equals]{\tex!\equals!}).
+               If the option \style{/yquant/group/aligned} is passed to the \tex!yquantgroup! environment, the command \tex!\shiftright! is implied after each linebreak or starred page break.
+
+               The option \tex!<where>! can take various forms:
+               \begin{itemize}
+                  \item It may be a natural number \texttt{1}, \texttt{2}, \dots, denoting the number of an alignment mark specified in a previous line.
+                  \item It may be the number \texttt{0}, denoting the very beginning of the line; this is useful if the \style{/yquant/group/aligned} option is given, but for a specific line, no alignment should be performed.
+                  \item It may be a \TeX{} dimension, in which case this dimension is directly added to the cursor (so it is a relative value).
+                     This is where passing the optional star makes most sense.
+                     If you want to position absolutely, you may first issue \tex!\shiftright[0]! followed by a shift by the dimension that you want.
+               \end{itemize}
+
+               \begin{warning}
+                  The macro is named \tex!\shiftright!; however, \Yquant{} does not enforce that the actual position is to the right of the current position.
+                  You may indeed be able to create overlapping circuits if you shift back to a previous position.
+               \end{warning}
+
+            \paragraph*{\tex!\pagebreak*!, \tex!\newpage*!, \tex!\clearpage*!, \tex!\cleardoublepage*!}
+               The page breaking commands are available only if the \tex!yquantgroup! was not enclosed in a \tex!tikzpicture!.
+               They will end the current picture environment, issue the original page breaking command, and start a new picture.
+               Hence, if you want to pass options globally to the picture, you should use the \style{/yquant/preamble} option for the \tex!yquantgroup!; the content of this key will be passed as options for every implicitly started \tex!tikzpicture!.
+
+               Usually, remembering the horizontal alignment marks on a new page does not make much sense.
+               For this reason, the commands will delete all alignment; use their starred versions to retain them.
+               If the option \style{/yquant/group/aligned} is passed to the \tex!yquantgroup! environment, the command \tex!\shiftright! is implied after the starred version of the page break.
+
+               Typically, you will not want to refer to named gates in a circuit on a different page; remember that if you need this feature, you must pass the \texttt{remember picture} key in the \style{/yquant/preamble} option, as this is a reference to another \tex!tikzpicture!.
+               Also don't forget to use the (\TikZ) \texttt{overlay} key on the corresponding path that references the node in order not to mess up with the bounding box (see the \TikZ{} documentation for those two keys).
+
+            \subsubsection{Configuration}
+               Loading the \pkg{groups} language extension will define several new configuration keys.
+
+               \begin{option}{group/every group}!!
+                  Style that is installed for every \tex!yquantgroup! and \tex!yquantgroup*! environment, as if it had been given as an option.
+                  The style's default path is \texttt{/tikz}.
+               \end{option}
+
+               \begin{option}{group/line separation}!5mm!
+                  This is the default vertical line separation that is inserted whenever a new line is issued in a \tex!yquantgroup!.
+               \end{option}
+
+               \begin{option}{group/aligned}!false!
+                  This boolean flag defines whether \tex!\shiftright! is automatically issued after \tex!\\! and the starred page breaking commands.
+               \end{option}
+
+               \begin{option}{preamble}!!
+                  This style may only be passed to the \tex!yquantgroup! alignment directly as an option; it is not available via \tex!\yquantset! and the like.
+                  It is only relevant if the \tex!yquantgroup! is not contained in a \tex!tikzpicture!.
+                  The content of this style will be given as an optional argument to the \tex!tikzpicture!; this is the recommended way to specify \TikZ{} options, as they are automatically preserved among page breaks.
+               \end{option}
+
+               \begin{option}{operators/every group circuit}!/yquant/operators/every subcircuit, /yquant/operators/subcircuit/frameless, /yquant/operators/subcircuit/name mangling=transparent!
+                  This style is installed for the \gate{subcircuit} that implicitly wraps each \tex!\circuit!.
+                  Note that some magic is carried out to ensure that the name mangling setting only applies to the \emph{direct} content of the \tex!\circuit!; any \gate{subcircuit}s within the \tex!\circuit! will use the default name mangling scheme.
+               \end{option}
+
+               \begin{option}{operators/every group equals}!shape=yquant-rectangle, align=center, inner xsep=1mm, x radius=2mm, y radius=2.47mm!
+                  This style is installed for every \tex!\equals!, which is internally realized similarly to a \gate{box} gate.
+               \end{option}
+
+            \subsubsection{Gates and operations}
+               No gates or operations may be used directly within the \tex!yquantgroup! environment, but all the usual \Yquant{} gates and operations are available within \tex!\registers! and \tex!\circuit!.
+               Additionally, within \tex!\circuit!, the \gate{import} gate is available.
+
+               \paragraph*{\yquant!import!}\label{gate:import}\leavevmode\\
+                  Syntax: \yquant!import <target>;! \\
+                  This is a pseudo\hyp gate that makes all the outer registers given in \tex!<target>! available in the current circuit.
+                  Consequently, the register names that are specified in \tex!<target>!, also ranges, do not refer to the registers in the \emph{current} \tex!\circuit!, but instead to those defined via \tex!\registers!.
+                  Therefore, it is for example possible to import all outer registers at once using \yquant!import -;!.
+                  Vector registers can also be imported partially.
+
+                  If additional content (\TeX{} commands such as \TikZ{} paths, non\hyp creation gates) is used within \tex!\registers!, everything that comes \emph{before} the declaration of a register will be copied into the \tex!\circuit! when the register is imported; for a vector, this refers to the index zero.
+                  Additionally, any additional content that comes \emph{after} the declaration of the last register will be copied directly after the last register was imported.
 
                   \begin{warning}[Out-of-order importing]
                      Note that it is principle possible to import registers out\hyp of\hyp order.
@@ -3496,20 +4968,113 @@ $=$
                   \end{adjustbox}
             }
 
-   \section{Wishlist}
-      This section contains some thoughts on future improvements and features.
-      \begin{itemize}
-         \item Support for more other languages. \\
-            Since version~0.3, \Yquant{} understands \pkg{qasm}.
-            It would be nice if \Yquant{} could also understand \texttt{OpenQASM} correctly.
-            The way \texttt{OpenQASM} treats operations is a bit different from \Yquant{} and also \pkg{qasm}.
-            Some machinery would be required to automatically carry out transversal gates; apart from that everything should be available in \Yquant.
-         \item Vertical layout. \\
-            Sometimes, long quantum circuits on a portrait page can be better represented in a vertical layout.
-            Also if lots of explanations are to be added, this becomes problematic in the horizontal version.
-            In principle, \Yquant's approach could allow for a simple key switch that changes horizontal to vertical.
-            Currently, this is largely unsupported by all quantum circuit packages except for \pkg{qpic}.
-      \end{itemize}
+   \section{Integration with other packages}
+      In general, \Yquant{} should not introduce incompatibilities with other packages.
+      However, the possibility to mix \Yquant{} code with arbitrary \TeX{} code may lead to certain expectations on how things should work, which may not always be met.
+      This is mainly due to the fact that \Yquant{} requires two passes of its content (see \cref{sec:pipeline}), as it has to measure the heights and depths of the individual gates.
+      Similar issues can for example also arise in \pkg{amsmath}'s \texttt{align} environment, which also has a measuring and a shipout stage.
+      If you run into an incompatibility using a macro from another package (or even plain \TeX), try the following:
+      \begin{enumerate}
+         \item Using a \TeX{} macro within \Yquant{} code will stop the \Yquant{} parser.
+            Hence, all gates following this macro will be ignored.
+            Did you remember to issue \tex!\yquant! in order to restart the parser after your macro? \\
+            \emph{Symptom:} No errors, but gates are missing
+         \item Is the macro robust?
+            Modern packages could automatically take care of this by a \tex!\protected! definition, but older ones may not.
+            Try to prefix the macro by \tex!\protect!. \\
+            \emph{Symptom:} Unexpected error messages
+         \item Does the macro depend on other macros defined \emph{within} the circuit?
+            The double pass may lead to problems.
+            If possible, define your macros outside of the \texttt{yquant} environment.
+            If this is not possible, make sure the definitions are expandable, then at measurement stage, \Yquant{} will do the expansion, so that you get the correct results. \\
+            \emph{Symptom:} Only the latest assignment will show up whenever the macro is used; the vertical spacing (for subcircuits, possibly also the horizontal spacing) may even be screwed.
+         \item Does the macro create output, using its own font?
+            If the output depends on the current position, this position will be completely wrong.
+            This is due to the fact that the macro is executed at the first pass only, where \Yquant{} does not know about any positions at all.
+            \compat{New in 0.6}The macro \tex!\yquantsecondpass! will defer its content so that it is executed only at the second pass, where positions are known.
+            It will also automatically restart the parser.
+            Note that \tex!\yquantsecondpass! will not expand its content.
+            If you need expansion, you may use \tex!\yquantesecondpass!, which uses \tex!\protected@edef!. \\
+            \emph{Symptom:} Content occurring in the wrong place or missing
+         \item Does the macro need to be executed at both passes?
+            There may be reasons for this, in particular if you use commands from \pkg{pgf}'s basic or system layer.
+            However, all custom macros will only be executed once, at the first pass.
+            \compat{New in 0.6}Wrap the macros in \tex!\yquantescape! in order to execute them both times.
+            The parser will automatically be restarted afterwards.
+            Note that \tex!\yquantescape! will not expand its content.
+            You may use \tex!\yquanteescape!, which will first expand its content using \tex!\protected@edef!.
+            Note that the content will first be executed, then stored for the second pass. \\
+            \emph{Symptom:} Content missing
+         \item If all of this did not work and the use case is interesting enough, please file a bug report.
+      \end{enumerate}
+
+      \subsection{\texorpdfstring{\TikZ}{TikZ}}
+         \Yquant{} is built on top of \TikZ{} an hence integrates well with \TikZ.
+         You can use all \tex!\path!-like comands as well as scopes and \Yquant{} will automatically take care of restarting the parser appropriately.
+         If it does not, this is very likely a bug, please file a report.
+
+         You should typically not use \tex!\tikzset!, as all changes made by this macro will only be executed in the first pass.
+         Instead, use \tex!\yquantset! and change the path appropriately: this macro will first store its argument (using \tex!\protected@edef!) for the second pass and then set the appropriate options also in the first pass.
+
+         Note that low\hyp level \pkg{pgf} functions are not altered by \Yquant; this would be highly inefficient.
+         \compat{New in 0.6}If you need to use them, wrap them in \tex!\yquantescape! or \tex!\yquanteescape!.
+
+      \subsection[\texorpdfstring{\pkg{beamer}}{beamer}]{\compat{New in 0.6}\pkg{beamer}}
+         \Yquant{} integrates with \pkg{beamer} overlays.
+         This means that you can use the overlay commands \tex!\only!, \tex!\alt!, \tex!\temporal!, \tex!\uncover!, \tex!\visible!, and \tex!\invisible! directly in your \Yquant{} code; the parser will automatically be restarted whenever necessary.
+         Note that the \texttt{*env} environments (\texttt{onlyenv}, \texttt{altenv}, \texttt{uncoverenv}, \texttt{visibleenv}, and \texttt{invisibleenv}) should \emph{not} be used within \Yquant{} code.
+
+         The macros \tex!\pause! and \tex!\uncover! are also supported to some degree (\tex!\uncover! with braces is fully supported).
+         They should work well in simple circuits, but unexpected results can be expected in more complex scenarios.
+         If you don't get appropriate results, use the aforementioned macros.
+
+         You may also use \tex!\note! inside \Yquant{} circuits.
+
+         Note that \Yquant{} does not overwrite the definitions of the \pkg{beamer} macros, which implies that you can also use them \emph{within} gates (e.g., for the \texttt{value} of a \gate{box}).
+         However, this means that the \Yquant{} parser must be running to detect these macros and take appropriate action.
+         Hence, if you interrupted the code via some special macros, make sure to restart the parser even if your next macro is, e.g., \tex!\only!.
+
+         Finally note that \tex!\only!, \tex!\alt!, and \tex!\temporal! are more special than the usual \Yquant\hyp code\hyp interrupting macros.
+         They will \emph{not} terminate the group that was opened for the current gate.
+         As a consequence, you can also use these macros for arguments.
+         Note that whenever you pass arguments to a gate using the \texttt{[<arguments>] <gate> <registers>;} syntax, the value of \texttt{<arguments>} is directly fed to \tex!\pgfkeys!, which \emph{does not} understand \pkg{beamer} macros.
+         Hence, you \emph{cannot} use, e.g., \tex!\only! \emph{within} the brackets.
+         However, you can wrap the arguments including the brackets as a whole in \tex!\only!---this happens before \Yquant{} relinquishes control to \tex!\pgfkeys! and therefore is executed as expected.
+         Since you can also pass multiple arguments to a gate by repeating \texttt{[<arguments>]}, this easily allows to combine arguments with and arguments without overlays.
+         \begin{example}[Using overlays for arguments]
+            \begin{minted}{tex}
+% \documentclass{beamer}
+\begin{frame}
+   \begin{tikzpicture}
+      \begin{yquant}
+         qubit a;
+         [fill=yellow]
+         \alt<2>{[draw=blue]}{[draw=green]}
+         \only<3>{[ultra thick]}
+         h a;
+      \end{yquant}
+   \end{tikzpicture}
+\end{frame}
+            \end{minted}
+            The Hadamard gate will always be filled yellow; its line color will be blue on the second frame and green on all other frames.
+            On the third frame, its line width is dramatically increased.
+         \end{example}
+
+% We have GitHub issues for this
+%   \section{Wishlist}
+%      This section contains some thoughts on future improvements and features.
+%      \begin{itemize}
+%         \item Support for more other languages. \\
+%            Since version~0.3, \Yquant{} understands \pkg{qasm}.
+%            It would be nice if \Yquant{} could also understand \texttt{OpenQASM} correctly.
+%            The way \texttt{OpenQASM} treats operations is a bit different from \Yquant{} and also \pkg{qasm}.
+%            Some machinery would be required to automatically carry out transversal gates; apart from that everything should be available in \Yquant.
+%         \item Vertical layout. \\
+%            Sometimes, long quantum circuits on a portrait page can be better represented in a vertical layout.
+%            Also if lots of explanations are to be added, this becomes problematic in the horizontal version.
+%            In principle, \Yquant's approach could allow for a simple key switch that changes horizontal to vertical.
+%            Currently, this is largely unsupported by all quantum circuit packages except for \pkg{qpic}.
+%      \end{itemize}
 
    \section{Changelog}
       \subsection*{2020-03-15: Version 0.1}
@@ -3556,7 +5121,7 @@ $=$
          Separate register height into a height and depth key. \\
          Introduce \texttt{overlay} key to disable height caluclation selectively. \\
          Change register style declaration, so that this is now always equivalent to creating an unnamed register followed by an \gate{init} gate with the given text.
-         Note: This may be a \textbf{breaking change} that cannot be compatibility\hyp protected---if you used \TeX{} conditionals involving \tex!\idx! for creation labels of registers, you will now need to either \tex!\protect! them all or just capitalize their first letter (which corresponds to auto\hyp\tex!protect!ed versions for \texttt{compat} at least \texttt{0.4}). \\
+         Note: This may be a \textbf{breaking change} that cannot be compatibility\hyp protected---if you used \TeX{} conditionals involving \tex!\idx! for creation labels of registers, you will now need to either \tex!\protect! them all or just capitalize their first letter (which corresponds to auto\hyp\tex!\protect!ed versions for \texttt{compat} at least \texttt{0.4}). \\
          Now use nodes for \gate{init} and \gate{output} gates. \\
          Change behavior of \gate{hspace} and \gate{align}: Now also extend if the wire is discarded afterwards. \\
          Introduce the commands \tex!\Ifnum!, \tex!\Ifcase!, \tex!\Or!, \tex!\Else!, \tex!\Fi!, \tex!\Unless! and \tex!\The! available for use within gates that behave like auto\hyp\tex!\protect!ed versions of their plain \TeX{} equivalents.
@@ -3580,5 +5145,20 @@ $=$
 
       \subsection*{2021-09-04: Version 0.5.1}
          Bugfix: The \gate{xx} gate style was not made available since version~0.4-alpha.
+
+      \subsection*{2021-12-28: Version 0.6}
+         Bugfix: Support to set the \style{/yquant/operators/subcircuit/seamless} property outside of \Yquant{} environments. \\
+         New: Support for \pkg{beamer}. \\
+         New macros: \tex!\yquantsecondpass!, \tex!\yquantesecondpass!, \tex!\yquantescape!, and \tex!\yquanteescape! for more fine\hyp grained control of when to execute macros. \\
+         Bugfix: the auto\hyp\tex!\protect!ed versions \tex!\Ifnum! etc. now also work in \gate{output} gates. \\
+         New gate: \gate{text}. \\
+         Introduce the \style{/yquant/operators/every rectangular box} style as a common ancestor of gates such as \gate{box}, \gate{h}, ... instead of using the \style{/yquant/operators/every box} style for this.
+         As a consequence, boxes can now be styled globally without affecting the other gates.
+         This new behavior is compatibility\hyp protected. \\
+         Bugfix: \gate{output}s can now be named. \\
+         Bugfix: Border angles of \texttt{yquant-ellipse} now work properly. \\
+         New configuration: \style{/yquant/register/default lazy name} \\
+         Documentation: Replace the wishlist by a section on integration with other packages. \\
+         Documentation: Include the examples of \pkg{qpic} in this manual.
 %END_FOLD
 \end{document}
\ No newline at end of file
diff --git a/graphics/pgf/contrib/yquant/tex/yquant-circuit.tex b/graphics/pgf/contrib/yquant/tex/yquant-circuit.tex
index 52cb435b2f..14f6a1f77b 100644
--- a/graphics/pgf/contrib/yquant/tex/yquant-circuit.tex
+++ b/graphics/pgf/contrib/yquant/tex/yquant-circuit.tex
@@ -217,16 +217,18 @@
 
 % restores the data captured for an uncontrolled operator and starts preparation
 % #1: \yquant@attrs@remaining
-% #2: \yquant@circuit@operator@targets
-% #3: \yquant@circuit@operator@mintarget
-% #4: \yquant@circuit@operator@maxtarget
-% #5: \yquant@circuit@operator@numtarget
-\protected\def\yquant@circuit@restore#1#2#3#4#5{%
+% #2: \yquant@lang@attr@name
+% #3: \yquant@circuit@operator@targets
+% #4: \yquant@circuit@operator@mintarget
+% #5: \yquant@circuit@operator@maxtarget
+% #6: \yquant@circuit@operator@numtarget
+\protected\def\yquant@circuit@restore#1#2#3#4#5#6{%
    \def\yquant@attrs@remaining{#1}%
-   \def\yquant@circuit@operator@targets{#2}%
-   \def\yquant@circuit@operator@mintarget{#3}%
-   \def\yquant@circuit@operator@maxtarget{#4}%
-   \def\yquant@circuit@operator@numtarget{#5}%
+   \def\yquant@lang@attr@name{#2}%
+   \def\yquant@circuit@operator@targets{#3}%
+   \def\yquant@circuit@operator@mintarget{#4}%
+   \def\yquant@circuit@operator@maxtarget{#5}%
+   \def\yquant@circuit@operator@numtarget{#6}%
    \yquant@circuit@operator@hasControlsfalse%
    \let\yquant@circuit@operator@pctrls=\empty%
    \def\yquant@circuit@operator@minpctrl{2147483647}%
@@ -323,10 +325,20 @@
 % sets the output of wires
 % #1: arbitrary register list
 \protected\def\yquant@circuit@output{%
-   \protected\def\idx{}%
+   \let\idx=\yquant@protectedempty%
+   \ifnum\yquant@compat>1 %
+      \let\Ifnum=\yquant@protectedempty%
+      \let\Ifcase=\yquant@protectedempty%
+      \let\Or=\yquant@protectedempty%
+      \let\Else=\yquant@protectedempty%
+      \let\Fi=\yquant@protectedempty%
+      \let\Unless=\yquant@protectedempty%
+      \let\The=\yquant@protectedempty%
+   \fi%
    \protected@csxappto{\yquant@prefix outputs}%
             {\yquant@circuit@restore%
                {\yquant@attrs@remaining}%
+               {\yquant@lang@attr@name}%
                {\unexpanded\expandafter{\yquant@circuit@operator@targets}}%
                {\yquant@circuit@operator@mintarget}{\yquant@circuit@operator@maxtarget}%
                {\yquant@circuit@operator@numtarget}%
diff --git a/graphics/pgf/contrib/yquant/tex/yquant-config.tex b/graphics/pgf/contrib/yquant/tex/yquant-config.tex
index a2d5a8fc9e..a50b2a4792 100644
--- a/graphics/pgf/contrib/yquant/tex/yquant-config.tex
+++ b/graphics/pgf/contrib/yquant/tex/yquant-config.tex
@@ -43,7 +43,9 @@
 % BEGIN_FOLD Register creation
 \pgfqkeys{/yquant}{%
    register/default name/.store in=%
-      \yquant@config@register@default@name%
+      \yquant@config@register@default@name,%
+   register/default lazy name/.store in=%
+      \yquant@config@register@default@lazyname%
 }
 \ifnum\yquant@compat<2 %
    \pgfqkeys{/yquant}{%
@@ -172,9 +174,25 @@
    }
 \fi
 \pgfqkeys{/yquant}{%
-   operators/every box/.style=%
-      {shape=yquant-rectangle, draw, align=center, inner xsep=1mm, x radius=2mm, y radius=2.47mm},%
+   operators/every text/.style=%
+      {shape=yquant-rectangle, align=center, inner xsep=1mm, x radius=2mm, y radius=2.47mm}%
 }
+\ifnum\yquant@compat<3 %
+   \pgfqkeys{/yquant}{%
+      % we did not have this style before 0.6, but for the ease of implementation, we just change the direction of inheritance---users of earlier compat versions will never use the style, so this is fully transparent
+      operators/every rectangular box/.style=%
+         {/yquant/operators/every box},%
+      operators/every box/.style=%
+         {shape=yquant-rectangle, draw, align=center, inner xsep=1mm, x radius=2mm, y radius=2.47mm}%
+   }
+\else
+   \pgfqkeys{/yquant}{%
+      operators/every rectangular box/.style=%
+         {shape=yquant-rectangle, draw, align=center, inner xsep=1mm, x radius=2mm, y radius=2.47mm},%
+      operators/every box/.style=%
+         {/yquant/operators/every rectangular box}%
+   }
+\fi
 \ifnum\yquant@compat<2 %
    \pgfqkeys{/yquant}{%
       operators/every custom gate/.style=%
@@ -200,7 +218,7 @@
    operators/every not/.style=%
       {shape=yquant-oplus, radius=1.3mm, draw},%
    operators/every pauli/.style=%
-      {/yquant/operators/every box},%
+      {/yquant/operators/every rectangular box},%
    operators/every phase/.style=%
       {shape=yquant-circle, radius=.5mm, fill},%
    operators/every slash/.style=%
@@ -208,7 +226,7 @@
    operators/every subcircuit/.style=%
       {},%
    operators/every subcircuit box/.style=%
-      {/yquant/operators/every box},%
+      {/yquant/operators/every rectangular box},%
    subcircuit box style/.style=%
       {/yquant/operators/every subcircuit box/.append style={#1}},%
    operators/this subcircuit box/.style=%
@@ -219,7 +237,11 @@
       {/yquant/operators/this subcircuit box/.append style={draw=none, inner sep=0pt}},%
    operators/subcircuit/seamless/.code=%
       {\pgfkeysalso{/yquant/operators/subcircuit/frameless, /yquant/register/default name=}%
-       \letcs\yquant@prevseamless{\yquant@prefix seamless}%
+       \ifdefined\yquant@prefix%
+          \csletcs{yquant@prevseamless}{\yquant@prefix seamless}%
+       \else%
+          \csletcs{yquant@prevseamless}{iffalse}%
+       \fi%
        \yquant@config@circuit@seamlesstrue},
    operators/subcircuit/name mangling/.is choice,%
    operators/subcircuit/name mangling/prefix or discard/.code=%
@@ -270,6 +292,7 @@
 % END_FOLD
 
 \def\yquant@config@register@default@name{\regidx}
+\let\yquant@config@register@default@lazyname=\empty
 \def\yquant@config@register@minimum@height{1.5mm}
 \def\yquant@config@register@minimum@depth{1.5mm}
 \def\yquant@config@register@sep{1mm}
diff --git a/graphics/pgf/contrib/yquant/tex/yquant-env.tex b/graphics/pgf/contrib/yquant/tex/yquant-env.tex
index c6e9f52b01..f26919c8d1 100644
--- a/graphics/pgf/contrib/yquant/tex/yquant-env.tex
+++ b/graphics/pgf/contrib/yquant/tex/yquant-env.tex
@@ -56,7 +56,7 @@
       \edef\yquant@prefix{yquant@env\the\yquant@env @}%
       \ifnum\yquant@env=1 %
          \yquantmeasuringtrue%
-         \yquant@env@substikz#1%
+         \yquant@env@substitute%
          \global\cslet{\yquant@prefix parameters}\empty%
       \else%
          \let\yquant@lang@reset@attrs@inputoutput=\yquant@lang@reset@attrs@inputoutput@subcircuit%
@@ -529,8 +529,29 @@
    \pgftransformreset%
 }
 
+\protected\def\yquant@env@protectidx{%
+   \ifundef\idx{%
+      \let\idx=\yquant@protectedempty%
+   }\relax%
+   \ifundef\reg{%
+      \let\reg=\yquant@protectedempty%
+   }\relax%
+   \ifundef\regidx{%
+      \let\regidx=\yquant@protectedempty%
+   }\relax%
+   \ifundef\len{%
+      \let\len=\yquant@protectedempty%
+   }\relax%
+}
+
+\let\yquant@env@substitutions=\empty
+\def\yquant@env@substitute{%
+   \forlistloop\@firstofone\yquant@env@substitutions%
+}
+
 % substitute the tikz commands (defined in \tikz@installcommands) so that they can be arbitrarily interleaved with yquant code. We patch \path, \scope, \endscope, \stopscope, their internal complements, and also patch \yquantset.
-\protected\def\yquant@env@substikz#1{%
+\listadd\yquant@env@substitutions\yquant@env@substikz
+\protected\def\yquant@env@substikz{%
    % \tikz@path@do@at@end is called after a path. Hence, it is an ideal candidate to re-invoke \yquant@env@scan. However, it is by default defined to be \tikz@lib@scope@check, and we need this definition for the scopes library to work correctly. But since \tikz@lib@scope@check is also called after a scope and the end of a scope, this is even better. Yet, we need to check whether the scopes library is present or not.
    \let\yquant@env@substikz@scopecheck=\tikz@lib@scope@check%
    \ifx\tikz@lib@scope@check\pgfutil@empty%
@@ -547,25 +568,31 @@
       \protected@csxappto{\yquant@prefix draw}{%
          \noexpand\path##1;%
       }%
-      #1%
+      \yquant@env@scan%
    }%
    % no need for \scoped, because it internally calls \scope.
    % We need to hack into \scope, but this is a bit tricky due to its argument handling. In order to get all optional arguments, including the possible animations library, correct, we change \tikz@scope@opt.
    \ifdefined\tikz@scope@opt%
       \let\yquant@env@substikz@scope=\tikz@scope@opt%
       \def\tikz@scope@opt[##1]{%
-         \protected@csxappto{\yquant@prefix draw}{%
-            \noexpand\tikz@scope@env[{##1}]%
-         }%
+         \begingroup%
+            \yquant@env@protectidx% scope options may contain \idx, \reg, and \regidx
+            \protected@csxappto{\yquant@prefix draw}{%
+               \noexpand\tikz@scope@env[{##1}]%
+            }%
+         \endgroup%
          \yquant@env@substikz@scope[{##1}]%
       }%
    \else%
       % this is for the arXiv, which has a very outdated version of TikZ
       \let\yquant@env@substikz@scope=\tikz@@scope@env%
       \def\tikz@@scope@env[##1]{%
-         \protected@csxappto{\yquant@prefix draw}{%
-            \noexpand\tikz@@scope@env[{##1}]%
-         }%
+         \begingroup%
+            \yquant@env@protectidx% scope options may contain \idx, \reg, and \regidx
+            \protected@csxappto{\yquant@prefix draw}{%
+               \noexpand\tikz@@scope@env[{##1}]%
+            }%
+         \endgroup%
          \yquant@env@substikz@scope[{##1}]%
       }%
    \fi%
@@ -580,14 +607,39 @@
    \let\stopscope=\endscope%
    % We define \yquantset as a pgfkeys-like macro. Anything else would deteriorate performance badly, as \pgfkeys, \pgfqkeys, or \tikzset are used a lot internally.
    \protected\def\yquantset##1{%
-      \protected@csxappto{\yquant@prefix draw}{%
-         \noexpand\pgfqkeys{/yquant}{##1}%
-      }%
+      \begingroup%
+         \yquant@env@protectidx% yquant options may contain \idx, \reg, and \regidx
+         \protected@csxappto{\yquant@prefix draw}{%
+            \noexpand\pgfqkeys{/yquant}{##1}%
+         }%
+      \endgroup%
       \pgfqkeys{/yquant}{##1}%
       \yquant@env@scan%
    }%
 }
 
+\listadd\yquant@env@substitutions\yquant@env@secondpass
+\protected\def\yquant@env@secondpass{%
+   \protected\long\def\yquantsecondpass##1{%
+      \csgappto{\yquant@prefix draw}{##1}%
+      \yquant@env@scan%
+   }%
+   \protected\long\def\yquantesecondpass##1{%
+      \protected@csxappto{\yquant@prefix draw}{##1}%
+      \yquant@env@scan%
+   }%
+   \protected\long\def\yquantescape##1{%
+      ##1%
+      \protected@csxappto{\yquant@prefix draw}{##1}%
+      \yquant@env@scan%
+   }%
+   \protected\long\def\yquanteescape##1{%
+      ##1%
+      \csgappto{\yquant@prefix draw}{##1}%
+      \yquant@env@scan%
+   }%
+}
+
 % Scan until the next non-space token is found and execute it as a csname
 \def\yquant@env@scan{%
    \begingroup%
@@ -604,6 +656,230 @@
    \yquant@env@scan%
 }
 
+\ifdefined\beamer@masterdecode
+   \expandafter\@firstoftwo
+\else
+   \expandafter\@secondoftwo
+\fi{%
+   \protected\def\yquant@env@check@findmacro{%
+      % we only put the beamer macros in here that effectively remove things from the input stream. Everything that is typeset in a special way will end the group
+      \ifx\yquant@env@nextchar\only%
+         \let\next=\yquant@env@beamer@only%
+      \else%
+         \ifx\yquant@env@nextchar\alt%
+            \let\next=\yquant@env@beamer@alt%
+         \else%
+            \ifx\yquant@env@nextchar\temporal%
+               \let\next=\yquant@env@beamer@temporal%
+            \else%
+               \ifx\yquant@env@nextchar\note%
+                  \let\next=\yquant@env@beamer@note%
+               \else%
+                  % in principle: \endgroup for all in here, but need to preserve \yquant@env@nextchar
+                  \ifx\yquant@env@nextchar\uncover%
+                     \endgroup%
+                     \let\next=\yquant@env@beamer@uncover%
+                  \else%
+                     \ifx\yquant@env@nextchar\visible%
+                        \endgroup%
+                        \let\next=\yquant@env@beamer@visible%
+                     \else%
+                        \ifx\yquant@env@nextchar\invisible%
+                           \endgroup%
+                           \let\next=\yquant@env@beamer@invisible%
+                        \else%
+                           \ifx\yquant@env@nextchar\onslide%
+                              \endgroup%
+                              \let\next=\yquant@env@beamer@onslide%
+                           \else%
+                              \ifx\yquant@env@nextchar\pause%
+                                 \endgroup%
+                                 \let\next=\yquant@env@beamer@pause%
+                              \else%
+                                 \ifx\yquant@env@nextchar\yquant@env@beamer@checkifactive%
+                                    \endgroup%
+                                    \let\yquant@env@beamer@checkifactive@true=\relax%
+                                    \let\next=\relax%
+                                 \else%
+                                    \endgroup%
+                                    \let\next=\relax%
+                                 \fi%
+                              \fi%
+                           \fi%
+                        \fi%
+                     \fi%
+                  \fi%
+               \fi%
+            \fi%
+         \fi%
+      \fi%
+   }%
+
+   \listadd\yquant@env@substitutions\yquant@env@substbeamer
+   \protected\def\yquant@env@substbeamer{%
+      \long\def\yquant@env@beamer@only@arga<##1>##2{%
+         \beamer@alt<##1>{\yquant@env@contscan##2}{\yquant@env@contscan}%
+      }%
+      \long\def\yquant@env@beamer@alt@arga<##1>##2##3{%
+         \beamer@alt<##1>{\yquant@env@contscan##2}{\yquant@env@contscan##3}%
+      }%
+      \protected\long\def\yquant@env@beamer@temporal\temporal<##1>##2##3##4{%
+         \temporal<##1>{\yquant@env@contscan##2}{\yquant@env@contscan##3}{\yquant@env@contscan##4}%
+      }%
+      % There's no need for the fakeinvisible or spacingcover macros, since we are within TikZ anyway
+      \mode<presentation>{
+         \protected\long\def\yquant@env@beamer@visibilitymacros##1##2##3##4{%
+            \yquant@env@beamer@visibilitymacros@flip##1%
+            \beamer@altget%
+               {\yquant@env@scan##3}%
+               {%
+                  \begingroup%
+                     \letcs\yquant@env@beamer@olddraw{\yquant@prefix draw}%
+                     \global\cslet{\yquant@prefix draw}\empty%
+                     \undef\yquant@env@beamer@checkifactive@true%
+                     ##2{\yquant@env@scan##3\yquant@env@beamer@checkifactive}%
+                     \csxdef{\yquant@prefix draw}{%
+                        \unexpanded\expandafter{\yquant@env@beamer@olddraw}%
+                        \ifx0##1%
+                           \noexpand\beamer@alt##4{}%
+                        \else%
+                           \noexpand\beamer@only##4%
+                        \fi%
+                        {%
+                           \unexpanded{##2}{%
+                              \unexpanded\expandafter\expandafter\expandafter{\csname\yquant@prefix draw\endcsname}%
+                           }%
+                        }%
+                     }%
+                     \expandafter%
+                  \endgroup%
+                  \ifdefined\yquant@env@beamer@checkifactive@true%
+                     \expandafter\@firstofone%
+                  \else%
+                     \expandafter\@gobble%
+                  \fi%
+                  \yquant@env@scan%
+              }%
+              ##4%
+         }
+         \newcommand<>\yquant@env@beamer@onslidenoargs[2]{%
+            \let\yquant@env@beamer@onslideappdraw=\empty%
+            \appto\yquant@env@beamer@onslideappdraw{\beamer@endpause}%
+            \yquant@for \i := 1 to \csname\yquant@prefix registers\endcsname{%
+               \eappto\yquant@env@beamer@onslideappdraw{\noexpand\yquant@circuit@flushwire{\i}}%
+            }%
+            \csxappto{\yquant@prefix draw}%
+                     {\unexpanded\expandafter{\yquant@env@beamer@onslideappdraw}}%
+            \beamer@alt##3%
+               {\csgappto{\yquant@prefix draw}{%
+                   \global\let\beamer@endpause=\empty%
+                }%
+                \yquant@env@scan}%
+               {\csgappto{\yquant@prefix draw}{%
+                   ##1%
+                   \gdef\beamer@endpause{##2}%
+                }%
+                \yquant@env@scan%
+               }%
+         }
+         % This is \beamer@inframenote, but we are always in a frame if we an in yquant
+         \newcommand<>{\yquant@env@beamer@note@}[2][]{%
+            \beamer@inframenote##3[{##1}]{##2}%
+            \yquant@env@contscan%
+         }
+      }%
+      \mode<article>{
+         \newcommand<>\yquant@env@beamer@uncover@[1]{%
+            \beamer@alt##2{\yquant@env@scan##1}{\yquant@env@scan}%
+         }
+         % we don't need \yquant@env@beamer@visible@ in this mode, since \uncover and \visible are equal (w.r.t. \ifx), so we will always end up with the \uncover path
+         \newcommand<>\yquant@env@beamer@invisible@[1]{%
+            \beamer@alt##2{\yquant@env@scan}{\yquant@env@scan##1}%
+         }
+         \newcommand<>{\yquant@env@beamer@note@}[2][]{\yquant@env@contscan}
+         \newrobustcmd\yquant@env@beamer@pause@[1][]{\yquant@env@scan}
+      }
+      \protected\def\yquant@env@beamer@onslide@{%
+         \@ifstar{\yquant@env@scan\only}%
+                 {\@ifnextchar+{\expandafter\yquant@env@beamer@visibleonslide\@gobble}%
+                               {\yquant@env@beamer@mainonslide}%
+                 }%
+      }%
+   }
+
+   \protected\def\yquant@env@beamer@only\only{\@ifnextchar<{\yquant@env@beamer@only@arga}%
+                                                           {\yquant@env@beamer@only@argb}}%
+   \long\def\yquant@env@beamer@only@argb#1{%
+      \beamer@ifnextcharospec{\yquant@env@beamer@only@argb@{#1}}{#1}%
+   }%
+   \long\def\yquant@env@beamer@only@argb@#1<#2>{%
+      \yquant@env@beamer@only@arga<#2>{#1}%
+   }%
+   \protected\def\yquant@env@beamer@alt\alt{\@ifnextchar<{\yquant@env@beamer@alt@arga}%
+                                                         {\yquant@env@beamer@alt@argb}}%
+   \long\def\yquant@env@beamer@alt@argb#1#2{%
+      \beamer@ifnextcharospec{\yquant@env@beamer@alt@argb@{#1}{#2}}{#1}%
+   }
+   \long\def\yquant@env@beamer@alt@argb@#1#2<#3>{%
+      \yquant@env@beamer@alt@arga<#3>{#1}{#2}%
+   }
+
+   \def\yquant@env@beamer@checkifactive{%
+      % this should not compare to anything else, but should also not give an error on expansion
+      \yquant@env@beamer@checkifactive@%
+   }
+   \let\yquant@env@beamer@checkifactive@=\empty%
+   \def\yquant@env@beamer@note\note{\yquant@env@beamer@note@}
+   % note: in article mode, the definitions of \uncover and \visible are identical, hence we will mistake \visible for \uncover (which is checked first); therefore, \yquant@env@beamer@uncover may be followed by \uncover or \visible, just take an arbitrary argument.
+   \def\yquant@env@beamer@uncover#1{\yquant@env@beamer@uncover@}
+   \def\yquant@env@beamer@visible\visible{\yquant@env@beamer@visible@}
+   \def\yquant@env@beamer@invisible\invisible{\yquant@env@beamer@invisible@}
+   \def\yquant@env@beamer@onslide\onslide{\yquant@env@beamer@onslide@}
+   \def\yquant@env@beamer@pause\pause{\yquant@env@beamer@pause@}
+
+   \mode<presentation>{
+      \long\def\yquant@env@beamer@visibilitymacros@flip#1#2#3#4{%
+         \ifx1#1%
+            \expandafter\@firstoftwo%
+         \else%
+            \expandafter\@secondoftwo%
+         \fi%
+         {#2{#4}{#3}}{#2{#3}{#4}}%
+      }
+      \newcommand<>\yquant@env@beamer@uncover@[1]{%
+         \yquant@env@beamer@visibilitymacros0\beamer@makecovered{#1}{#2}%
+      }
+      \newcommand<>\yquant@env@beamer@visible@[1]{%
+         \yquant@env@beamer@visibilitymacros0\beamer@reallymakeinvisible{#1}{#2}%
+      }
+      \newcommand<>\yquant@env@beamer@invisible@[1]{%
+         \yquant@env@beamer@visibilitymacros1\beamer@reallymakeinvisible{#1}{#2}%
+      }
+      \newrobustcmd\yquant@env@beamer@pause@[1][]{%
+         \ifblank{#1}%
+            {\stepcounter{beamerpauses}}%
+            {\setcounter{beamerpauses}{#1}}%
+         \yquant@env@beamer@onslidenoargs<\value{beamerpauses}->\beamer@startcovered\beamer@endcovered%
+      }
+   }
+   \mode<article>{
+      \newcommand<>\yquant@env@beamer@onslidenoargs[2]{}
+   }
+   \newcommand<>{\yquant@env@beamer@visibleonslide}{%
+      \@ifnextchar\bgroup{\yquant@env@beamer@visible@#1}%
+                         {\yquant@env@beamer@onslidenoargs#1\beamer@begininvisible\beamer@endinvisible}%
+   }
+   \newcommand<>{\yquant@env@beamer@mainonslide}{%
+      \@ifnextchar\bgroup{\yquant@env@beamer@uncover@#1}%
+                         {\yquant@env@beamer@onslidenoargs#1\beamer@startcovered\beamer@endcovered}%
+   }
+}{%
+   \def\yquant@env@check@findmacro{%
+      \endgroup%
+      \let\next=\relax%
+   }
+}%
+
 \protected\def\yquant@env@check@{%
    \let\next=\relax%
    % Here we assume standard catcodes for A and [, but our language specification also requires this implicitly.
@@ -625,8 +901,7 @@
                   \let\next=\yquant@env@gobblepar%
                \else%
                   \ifcat\noexpand\yquant@env@nextchar\relax%
-                     \endgroup%
-                     \let\next=\relax%
+                     \yquant@env@check@findmacro%
                   \else%
                      \PackageError{yquant.sty}%
                         {Invalid yquant syntax: `\meaning\yquant@env@nextchar'}%
diff --git a/graphics/pgf/contrib/yquant/tex/yquant-lang.tex b/graphics/pgf/contrib/yquant/tex/yquant-lang.tex
index 8658d3af9f..cc882a7ffb 100644
--- a/graphics/pgf/contrib/yquant/tex/yquant-lang.tex
+++ b/graphics/pgf/contrib/yquant/tex/yquant-lang.tex
@@ -298,7 +298,7 @@
       % usually, we will not be in a tikzpicture here, so all the commands that abbreviate some path operation are undefined!
       \tikz@installcommands%
       % While we want the content to be expanded, protect the most likely TikZ commands - the same ones that we usually substitute in \yquant@env@substikz.
-      \protected\def\path{}%
+      \let\path=\yquant@protectedempty%
       \let\scoped=\path%
       \let\scope=\path%
       \let\endscope=\path%
@@ -362,7 +362,7 @@
 
 \def\yquantdefinebox@#1#2{%
    \@ifnextchar[{\yquantdefinebox@i{#1}{#2}}%
-                {\yquantdefinebox@i{#1}{#2}[/yquant/operators/every box]}%
+                {\yquantdefinebox@i{#1}{#2}[/yquant/operators/every rectangular box]}%
 }
 
 \protected\long\def\yquantdefinebox@i#1#2[#3]#4{%
@@ -393,6 +393,16 @@
    }
 \yquant@langhelper@setup@attrs{box}{value}{}
 
+\yquant@langhelper@declare@command%
+   {text}%
+   \yquant@register@get@allowmultitrue%
+   {%
+      \expandafter\yquant@prepare%
+         \expandafter{\yquant@lang@attr@value}%
+         {/yquant/operators/every text}%
+   }
+\yquant@langhelper@setup@attrs{text}{value}{}
+
 % Hadamard
 \yquantdefinebox{h}{$H$}
 
@@ -601,6 +611,7 @@
    {init}%
    {%
       \yquant@register@get@allowmultitrue%
+      \let\yquant@config@register@default@lazyname=\empty%
       % we will count how many registers contain the "clean" flag, and only if this is equal to the number of targets, we apply the shift.
       \count8=0 %
    }%
diff --git a/graphics/pgf/contrib/yquant/tex/yquant-prepare.tex b/graphics/pgf/contrib/yquant/tex/yquant-prepare.tex
index fb46e4e7d1..9869a61a76 100644
--- a/graphics/pgf/contrib/yquant/tex/yquant-prepare.tex
+++ b/graphics/pgf/contrib/yquant/tex/yquant-prepare.tex
@@ -293,7 +293,7 @@
 }
 \protected\long\def\yquant@prepare@finalize#1#2{%
    % We now know the dimensions of all the registers (though we didn't bother with the height of the control knobs [if present], we just assume they are too small to change this).
-   \protected\def\idx{}%#
+   \let\idx=\yquant@protectedempty%
    \yquant@prepare@ifs@set%
    \let\yquant@prepare@append=\empty%
    \yquant@sort\yquant@prepare@sort%
diff --git a/graphics/pgf/contrib/yquant/tex/yquant-registers.tex b/graphics/pgf/contrib/yquant/tex/yquant-registers.tex
index 97762cf3dd..41a472821f 100644
--- a/graphics/pgf/contrib/yquant/tex/yquant-registers.tex
+++ b/graphics/pgf/contrib/yquant/tex/yquant-registers.tex
@@ -166,9 +166,56 @@
       \else%
          \def\idx{0}%
       \fi%
-      % pre-set y position
-      \yquant@for \idx := \idx to \numexpr \len -1\relax {%
-         \yquant@prepare@create\reg\idx\yquant@register@type@q%
+      % define text macros
+      \ifnum\len=1 %
+         \let\regidx=\reg%
+      \else%
+         \def\regidx{\reg[\idx]}%
+      \fi%
+      \numdef\yquant@circuit@operator@mintarget{\csname\yquant@prefix registers\endcsname+1}%
+      \begingroup%
+         \yquant@for \idx := \idx to \numexpr \len -1\relax {%
+            \yquant@prepare@create\reg\idx\yquant@register@type@q%
+         }%
+      \endgroup%
+      \ifx\yquant@config@register@default@lazyname\empty%
+         \expandafter\@gobble%
+      \else%
+         \expandafter\@firstofone%
+      \fi%
+      {%
+         \let\yquant@lang@attr@value=\yquant@config@register@default@lazyname%
+         % gather details about the created registers
+         \letcs\yquant@circuit@operator@maxtarget{\yquant@prefix registers}%
+         \numdef\yquant@circuit@operator@numtarget{\yquant@circuit@operator@maxtarget-\yquant@circuit@operator@mintarget+1}%
+         \edef\yquant@circuit@operator@targets{%
+            \yquant@list@range%
+               \yquant@circuit@operator@mintarget%
+               \yquant@circuit@operator@maxtarget%
+         }%
+         \let\yquant@circuit@operator@pctrls=\empty%
+         \def\yquant@circuit@operator@minpctrl{2147483647}%
+         \def\yquant@circuit@operator@maxpctrl{0}%
+         \let\yquant@circuit@operator@numpctrl=\yquant@circuit@operator@maxpctrl%
+         \let\yquant@circuit@operator@nctrls=\empty%
+         \let\yquant@circuit@operator@minnctrl=\yquant@circuit@operator@minpctrl%
+         \let\yquant@circuit@operator@maxnctrl=\yquant@circuit@operator@maxpctrl%
+         \let\yquant@circuit@operator@numnctrl=\yquant@circuit@operator@numpctrl%
+         \let\yquant@circuit@operator@minctrl=\yquant@circuit@operator@mintarget%
+         \let\yquant@circuit@operator@maxctrl=\yquant@circuit@operator@maxtarget%
+         % there are no multi inits in this context
+         \preto\yquant@attrs@remaining{internal/move label,}%
+         \def\yquant@config@operator@minimum@width{0pt}%
+         \unless\ifx\yquant@lang@attr@value\empty%
+            % make sure to immediately remove the "clear" marker again if we have a text
+            \yquant@for \i := \yquant@circuit@operator@mintarget to \yquant@circuit@operator@maxtarget {%
+               \yquant@register@execclear@lastgate{\i}{init}%
+            }%
+         \fi%
+         \expandafter\yquant@prepare%
+            \expandafter{\yquant@lang@attr@value}%
+            {/yquant/every label, /yquant/every initial label,%
+             /yquant/every qubit label}%
       }%
    \endgroup%
 }
@@ -216,8 +263,8 @@
 }
 \endgroup
 
-\protected\def\yquant@register@get@ids@@index{}
-\protected\def\yquant@register@get@ids@@multi{}
+\let\yquant@register@get@ids@@index=\yquant@protectedempty
+\let\yquant@register@get@ids@@multi=\yquant@protectedempty
 
 \def\yquant@register@get@ids@outerlist#1{%
    \ifyquant@firsttoken\yquant@register@get@ids@@multi{#1}{%
@@ -557,8 +604,8 @@
    \yquant@register@get@id#1{\trim@spaces{#2}[\trim@spaces{\trim@spaces#3}]}%
 }
 
-\let\yquant@register@multi=\empty%
-\protected\def\yquant@register@multi@contiguous{}%
+\let\yquant@register@multi=\empty
+\let\yquant@register@multi@contiguous=\yquant@protectedempty
 
 % splits \yquant@register@get@ids@list into a list of contiguous parts
 \protected\def\yquant@register@multi@splitparts{%
@@ -738,7 +785,7 @@
 }
 
 % This plays a similar role: It must never be expanded before the tikz command is invoked (because it does not exist).
-\protected\def\nodepart{}
+\let\nodepart=\yquant@protectedempty
 
 \def\yquant@register@get@y@unprotected#1{%
    \ifcsname\yquant@prefix registermap@#1\endcsname%
diff --git a/graphics/pgf/contrib/yquant/tex/yquant-shapes.tex b/graphics/pgf/contrib/yquant/tex/yquant-shapes.tex
index 88cddd66dd..ea62802b2b 100644
--- a/graphics/pgf/contrib/yquant/tex/yquant-shapes.tex
+++ b/graphics/pgf/contrib/yquant/tex/yquant-shapes.tex
@@ -192,8 +192,7 @@
       \@tempdima=\pgf@x%
       \@tempdimb=\pgf@y%
       \pgfpointborderellipse{\pgfqpoint{\@tempdima}{\@tempdimb}}%
-                            {\pgfqpoint{.707107\dimexpr\xradius\relax}%
-                                       {.707107\dimexpr\yradius\relax}}%
+                            {\pgfqpoint{\xradius}{\yradius}}%
    }%
    \backgroundpath{%
       \pgfpathellipse{\pgfpointorigin}%
@@ -202,8 +201,8 @@
    }%
    \clippath{%
       \pgfpathellipse{\pgfpointorigin}%
-                     {\pgfqpoint{\dimexpr\xradius+.5\pgflinewidth}{0pt}}%
-                     {\pgfqpoint{0pt}{\dimexpr\yradius+.5\pgflinewidth}}%
+                     {\pgfqpoint{\dimexpr\xradius+.5\pgflinewidth\relax}{0pt}}%
+                     {\pgfqpoint{0pt}{\dimexpr\yradius+.5\pgflinewidth\relax}}%
    }%
 }
 
diff --git a/graphics/pgf/contrib/yquant/tex/yquant-tools.tex b/graphics/pgf/contrib/yquant/tex/yquant-tools.tex
index 65880b995f..f30dc308bc 100644
--- a/graphics/pgf/contrib/yquant/tex/yquant-tools.tex
+++ b/graphics/pgf/contrib/yquant/tex/yquant-tools.tex
@@ -37,6 +37,8 @@
 \long\def\@fourthoffive#1#2#3#4#5{#4} % unused
 \long\def\@fifthoffive#1#2#3#4#5{#5}
 
+\protected\def\yquant@protectedempty{}
+
 % Loop #1 from min(#2, #3) to max(#2, #3), executing #4
 \protected\def\yquant@for #1:=#2to#3#{%
    \yquant@for@aux#1{#2}{#3}%
diff --git a/graphics/pgf/contrib/yquant/tex/yquant.sty b/graphics/pgf/contrib/yquant/tex/yquant.sty
index a3bda686b8..75b1cfd214 100644
--- a/graphics/pgf/contrib/yquant/tex/yquant.sty
+++ b/graphics/pgf/contrib/yquant/tex/yquant.sty
@@ -15,7 +15,7 @@
 %
 % The Current Maintainer of this work is Benjamin Desef.
 \NeedsTeXFormat{LaTeX2e}
-\ProvidesPackage{yquant}[2021/09/04 v0.5.1 Yet another quantum circuit library for LaTeX]
+\ProvidesPackage{yquant}[2021/12/28 v0.6 Yet another quantum circuit library for LaTeX]
 
 \RequirePackage{etoolbox}[2018/02/11]
 \RequirePackage{tikz}[2015/08/29]
@@ -23,16 +23,16 @@
 \RequirePackage{xkeyval}[2005/05/07]
 \usetikzlibrary{arrows.meta,decorations.pathreplacing,decorations.pathmorphing}
 
-\define@choicekey+{yquant.sty}{compat}[\val\yquant@compat]{newest,0.3,0.4}{
+\define@choicekey+{yquant.sty}{compat}[\val\yquant@compat]{newest,0.3,0.4,0.6}{
    \ifnum\yquant@compat=0 %
-      \def\yquant@compat{2} % current version
+      \def\yquant@compat{3} % current version
    \fi%
 }{
    \PackageWarning{yquant.sty}{Invalid value for `compat` key specified. Using `0.3`.}
 }
 \ProcessOptionsX
 \unless\ifdefined\yquant@compat
-   \PackageWarning{yquant.sty}{Please specify the `compat` key for yquant. Using `0.3`. Current compatibility version `0.4`.}
+   \PackageWarning{yquant.sty}{Please specify the `compat` key for yquant. Using `0.3`. Current compatibility version `0.6`.}
    \def\yquant@compat{1}
 \fi
 
diff --git a/graphics/pgf/contrib/yquant/tex/yquantlanguage-groups.sty b/graphics/pgf/contrib/yquant/tex/yquantlanguage-groups.sty
index e8330d731e..1ea78cace6 100644
--- a/graphics/pgf/contrib/yquant/tex/yquantlanguage-groups.sty
+++ b/graphics/pgf/contrib/yquant/tex/yquantlanguage-groups.sty
@@ -15,9 +15,9 @@
 %
 % The Current Maintainer of this work is Benjamin Desef.
 \NeedsTeXFormat{LaTeX2e}
-\ProvidesPackage{yquantlanguage-groups}[2021/08/14 v0.5 yquant-groups]
+\ProvidesPackage{yquantlanguage-groups}[2021/08/14 v0.6 yquant-groups]
 
-\RequirePackage{yquant}[2021/08/14]
+\RequirePackage{yquant}[2021/12/24]
 
 % BEGIN_FOLD Config
 \newif\ifyquantgroup@config@aligned
@@ -173,7 +173,7 @@
    \edef\yquant@prefix{yquant@env\the\yquant@env @}%
    \ifnum\yquant@env=1 %
       \yquantmeasuringtrue%
-      \yquant@env@substikz#1%
+      \yquant@env@substitute%
       \global\cslet{\yquant@prefix parameters}\empty%
    \else%
       \let\yquant@lang@reset@attrs@inputoutput=\yquant@lang@reset@attrs@inputoutput@subcircuit%
@@ -188,7 +188,7 @@
    \let\yquant@parent=\yquantgroup@parent%
    \let\yquant@prefix=\yquantgroup@prefix%
    \yquantmeasuringtrue%
-   \yquant@env@substikz#1%
+   \yquant@env@substitute%
    \global\cslet{\yquant@prefix parameters}\empty%
 }\relax{%
    \PackageError{yquant.sty}{Internal error}%
diff --git a/graphics/pgf/contrib/yquant/tex/yquantlanguage-qasm.sty b/graphics/pgf/contrib/yquant/tex/yquantlanguage-qasm.sty
index d37aa6b9f0..86128e643c 100644
--- a/graphics/pgf/contrib/yquant/tex/yquantlanguage-qasm.sty
+++ b/graphics/pgf/contrib/yquant/tex/yquantlanguage-qasm.sty
@@ -1,7 +1,7 @@
 % yquantlanguage-qasm.sty
 %  Extend yquant to understand qasm syntax.
 %
-% Copyright 2020 Benjamin Desef
+% Copyright 2021 Benjamin Desef
 %
 % This work may be distributed and/or modified under the conditions of the LaTeX Project
 % Public License, either version 1.3c of this license or (at your option) any later
@@ -15,9 +15,9 @@
 %
 % The Current Maintainer of this work is Benjamin Desef.
 \NeedsTeXFormat{LaTeX2e}
-\ProvidesPackage{yquantlanguage-qasm}[2021/03/27 v0.4 yquant-qasm]
+\ProvidesPackage{yquantlanguage-qasm}[2021/12/24 v0.6 yquant-qasm]
 
-\RequirePackage{yquant}[2021/03/27]
+\RequirePackage{yquant}[2021/12/24]
 
 % BEGIN_FOLD Environment definitions
 \begingroup
@@ -338,13 +338,13 @@
 % BEGIN_FOLD Configuration
 \pgfkeys{%
    /yquant/operators/every s/.style={%
-      /yquant/operators/every box%
+      /yquant/operators/every rectangular box%
    },%
    /yquant/operators/every t/.style={%
-      /yquant/operators/every box%
+      /yquant/operators/every rectangular box%
    },%
    /yquant/operators/every utwo/.style={%
-      /yquant/operators/every box%
+      /yquant/operators/every rectangular box%
    },
    /qasm/zero/.store in=%
       \qasm@config@zero,%
-- 
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