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diff --git a/Master/texmf-dist/source/latex/l3kernel/l3box.dtx b/Master/texmf-dist/source/latex/l3kernel/l3box.dtx new file mode 100644 index 00000000000..1947f85b356 --- /dev/null +++ b/Master/texmf-dist/source/latex/l3kernel/l3box.dtx @@ -0,0 +1,1237 @@ +% \iffalse meta-comment +% +%% File: l3box.dtx Copyright (C) 2005-2011 The LaTeX3 Project +%% +%% It may be distributed and/or modified under the conditions of the +%% LaTeX Project Public License (LPPL), either version 1.3c of this +%% license or (at your option) any later version. The latest version +%% of this license is in the file +%% +%% http://www.latex-project.org/lppl.txt +%% +%% This file is part of the "expl3 bundle" (The Work in LPPL) +%% and all files in that bundle must be distributed together. +%% +%% The released version of this bundle is available from CTAN. +%% +%% ----------------------------------------------------------------------- +%% +%% The development version of the bundle can be found at +%% +%% http://www.latex-project.org/svnroot/experimental/trunk/ +%% +%% for those people who are interested. +%% +%%%%%%%%%%% +%% NOTE: %% +%%%%%%%%%%% +%% +%% Snapshots taken from the repository represent work in progress and may +%% not work or may contain conflicting material! We therefore ask +%% people _not_ to put them into distributions, archives, etc. without +%% prior consultation with the LaTeX3 Project. +%% +%% ----------------------------------------------------------------------- +% +%<*driver|package> +\RequirePackage{l3names} +\GetIdInfo$Id: l3box.dtx 2478 2011-06-19 21:34:23Z joseph $ + {L3 Experimental boxes} +%</driver|package> +%<*driver> +\documentclass[full]{l3doc} +\begin{document} + \DocInput{\jobname.dtx} +\end{document} +%</driver> +% \fi +% +% \title{^^A +% The \pkg{l3box} package\\ Boxes^^A +% \thanks{This file describes v\ExplFileVersion, +% last revised \ExplFileDate.}^^A +% } +% +% \author{^^A +% The \LaTeX3 Project\thanks +% {^^A +% E-mail: +% \href{mailto:latex-team@latex-project.org} +% {latex-team@latex-project.org}^^A +% }^^A +% } +% +% \date{Released \ExplFileDate} +% +% \maketitle +% +% \begin{documentation} +% +% There are three kinds of box operations: horizontal mode denoted +% with prefix |\hbox_|, vertical mode with prefix |\vbox_|, and the +% generic operations working in both modes with prefix |\box_|. +% +% \section{Creating and initialising boxes} +% +% \begin{function}{\box_new:N, \box_new:c} +% \begin{syntax} +% \cs{box_new:N} \meta{box} +% \end{syntax} +% Creates a new \meta{box} or raises an error if the name is +% already taken. The declaration is global. The \meta{box} will +% initially be void. +% \end{function} +% +% \begin{function}{\box_clear:N, \box_clear:c} +% \begin{syntax} +% \cs{box_clear:N} \meta{box} +% \end{syntax} +% Clears the content of the \meta{box} by setting the box equal to +% \cs{c_void_box} within the current \TeX{} group level. +% \end{function} +% +% \begin{function}{\box_gclear:N, \box_gclear:c} +% \begin{syntax} +% \cs{box_gclear:N} \meta{box} +% \end{syntax} +% Clears the content of the \meta{box} by setting the box equal to +% \cs{c_void_box} globally. +% \end{function} +% +% \begin{function}{\box_clear_new:N, \box_clear_new:c} +% \begin{syntax} +% \cs{box_clear_new:N} \meta{box} +% \end{syntax} +% If the \meta{box} is not defined, globally creates it. If the \meta{box} +% is defined, +% clears the content of the \meta{box} by setting the box equal to +% \cs{c_void_box} within the current \TeX{} group level. +% \end{function} +% +% \begin{function}{\box_gclear_new:N, \box_gclear_new:c} +% \begin{syntax} +% \cs{box_gclear_new:N} \meta{box} +% \end{syntax} +% If the \meta{box} is not defined, globally creates it. If the \meta{box} +% is defined, +% clears the content of the \meta{box} by setting the box equal to +% \cs{c_void_box} globally. +% \end{function} +% +% \begin{function} +% {\box_set_eq:NN, \box_set_eq:cN, \box_set_eq:Nc, \box_set_eq:cc} +% \begin{syntax} +% \cs{box_set_eq:NN} \meta{box1} \meta{box2} +% \end{syntax} +% Sets the content of \meta{box1} equal to that of \meta{box2}. This +% assignment is restricted to the current \TeX{} group level. +% \end{function} +% +% \begin{function} +% {\box_gset_eq:NN, \box_gset_eq:cN, \box_gset_eq:Nc, \box_gset_eq:cc} +% \begin{syntax} +% \cs{box_gset_eq:NN} \meta{box1} \meta{box2} +% \end{syntax} +% Sets the content of \meta{box1} equal to that of \meta{box2} globally. +% \end{function} +% +% \begin{function} +% { +% \box_set_eq_clear:NN, \box_set_eq_clear:cN, +% \box_set_eq_clear:Nc, \box_set_eq_clear:cc +% } +% \begin{syntax} +% \cs{box_set_eq_clear:NN} \meta{box1} \meta{box2} +% \end{syntax} +% Sets the content of \meta{box1} within the current \TeX{} group +% equal to that of \meta{box2}, then clears \meta{box2} globally. +% \end{function} +% +% \begin{function} +% { +% \box_gset_eq_clear:NN, \box_gset_eq_clear:cN, +% \box_gset_eq_clear:Nc, \box_gset_eq_clear:cc +% } +% \begin{syntax} +% \cs{box_gset_eq_clear:NN} \meta{box1} \meta{box2} +% \end{syntax} +% Sets the content of \meta{box1} equal to that of \meta{box2}, then +% clears \meta{box2}. These assignments are global. +% \end{function} +% +% \section{Using boxes} +% +% \begin{function}{\box_use:N, \box_use:c} +% \begin{syntax} +% \cs{box_use:N} \meta{box} +% \end{syntax} +% Inserts the current content of the \meta{box} onto the current +% list for typesetting. +% \begin{texnote} +% This is the \TeX{} primitive \cs{copy}. +% \end{texnote} +% \end{function} +% +% \begin{function}{\box_use_clear:N, \box_use_clear:c} +% \begin{syntax} +% \cs{box_use_clear:N} \meta{box} +% \end{syntax} +% Inserts the current content of the \meta{box} onto the current +% list for typesetting, then globally clears the content of the +% \meta{box}. +% \begin{texnote} +% This is the \TeX{} primitive \cs{box}. +% \end{texnote} +% \end{function} +% +% \begin{function}{\box_move_right:nn, \box_move_left:nn} +% \begin{syntax} +% \cs{box_move_right:nn} \Arg{dimexpr} \Arg{box function} +% \end{syntax} +% This function operates in vertical mode, and inserts the +% material specified by the \meta{box function} +% such that its reference point is displaced horizontally by the given +% \meta{dimexpr} from the reference point for typesetting, to the right +% or left as appropriate. The \meta{box function} should be +% a box opeeration such as |\box_use:N \<box>| or a \enquote{raw} +% box specification such as |\vbox:n { xyz }|. +% \end{function} +% +% \begin{function}{\box_move_up:nn, \box_move_down:nn} +% \begin{syntax} +% \cs{box_move_up:nn} \Arg{dimexpr} \Arg{box function} +% \end{syntax} +% This function operates in horizontal mode, and inserts the +% material specified by the \meta{box function} +% such that its reference point is displaced vertical by the given +% \meta{dimexpr} from the reference point for typesetting, up +% or down as appropriate. The \meta{box function} should be +% a box opeeration such as |\box_use:N \<box>| or a \enquote{raw} +% box specification such as |\vbox:n { xyz }|. +% \end{function} +% +% \section{Measuring and setting box dimensions} +% +% \begin{function}{\box_dp:N, \box_dp:c} +% \begin{syntax} +% \cs{box_dp:N} \meta{box} +% \end{syntax} +% Calculates the depth (below the baseline) of the \meta{box} +% and leaves this in the input stream. The output of this function +% is suitable for use in a \meta{dimension expression} for +% calculations. +% \begin{texnote} +% This is the \TeX{} primitive \cs{dp}. +% \end{texnote} +% \end{function} +% +% \begin{function}{\box_ht:N, \box_ht:c} +% \begin{syntax} +% \cs{box_ht:N} \meta{box} +% \end{syntax} +% Calculates the height (above the baseline) of the \meta{box} +% and leaves this in the input stream. The output of this function +% is suitable for use in a \meta{dimension expression} for +% calculations. +% \begin{texnote} +% This is the \TeX{} primitive \cs{ht}. +% \end{texnote} +% \end{function} +% +% \begin{function}{\box_wd:N, \box_wd:c} +% \begin{syntax} +% \cs{box_wd:N} \meta{box} +% \end{syntax} +% Calculates the width of the \meta{box} and leaves this in the +% input stream. The output of this function is suitable for use in a +% \meta{dimension expression} for calculations. +% \begin{texnote} +% This is the \TeX{} primitive \cs{wd}. +% \end{texnote} +% \end{function} +% +% \begin{function}{\box_set_dp:Nn, \box_set_dp:cn} +% \begin{syntax} +% \cs{box_set_dp:Nn} \meta{box} \Arg{dimension expression} +% \end{syntax} +% Set the depth (below the baseline) of the \meta{box} to the value of +% the \Arg{dimension expression}. This is a global assignment. +% \end{function} +% +% \begin{function}{\box_set_ht:Nn, \box_set_ht:cn} +% \begin{syntax} +% \cs{box_set_ht:Nn} \meta{box} \Arg{dimension expression} +% \end{syntax} +% Set the height (above the baseline) of the \meta{box} to the value of +% the \Arg{dimension expression}. This is a global assignment. +% \end{function} +% +% \begin{function}{\box_set_wd:Nn, \box_set_wd:cn} +% \begin{syntax} +% \cs{box_set_wd:Nn} \meta{box} \Arg{dimension expression} +% \end{syntax} +% Set the width of the \meta{box} to the value of the +% \Arg{dimension expression}. This is a global assignment. +% \end{function} +% +% \section{Box conditionals} +% +% \begin{function}[EXP,pTF]{\box_if_empty:N, \box_if_empty:c} +% \begin{syntax} +% \cs{box_if_empty_p:N} \meta{box} +% \cs{box_if_empty:NTF} \meta{box} \Arg{true code} \Arg{false code} +% \end{syntax} +% Tests if \meta{box} is a empty (equal to \cs{c_empty_box}). +% The branching versions then leave either +% \meta{true code} or \meta{false code} in the input stream, as +% appropriate to the truth of the test and the variant of the function +% chosen. The logical truth of the test is left in the input stream by +% the predicate version. +% \end{function} +% +% \begin{function}[EXP,pTF]{\box_if_horizontal:N, \box_if_horizontal:c} +% \begin{syntax} +% \cs{box_if_horizontal_p:N} \meta{box} +% \cs{box_if_horizontal:NTF} \meta{box} \Arg{true code} \Arg{false code} +% \end{syntax} +% Tests if \meta{box} is a horizontal box. The branching +% versions then leave either \meta{true code} or \meta{false code} +% in the input stream, as appropriate to the truth of the test and +% the variant of the function chosen. The logical truth of the test +% is left in the input stream by the predicate version. +% \end{function} +% +% \begin{function}[EXP,pTF]{\box_if_vertical:N, \box_if_vertical:c} +% \begin{syntax} +% \cs{box_if_vertical_p:N} \meta{box} +% \cs{box_if_vertical:NTF} \meta{box} \Arg{true code} \Arg{false code} +% \end{syntax} +% Tests if \meta{box} is a vertical box. The branching +% versions then leave either \meta{true code} or \meta{false code} +% in the input stream, as appropriate to the truth of the test and +% the variant of the function chosen. The logical truth of the test +% is left in the input stream by the predicate version. +% \end{function} +% +% \section{The last box inserted} +% +% \begin{variable}{\l_last_box} +% This is a box containing the last item added to the current partial +% list, except in the case of the main vertical list (main galley), in +% which case this box is always void. Notice that although this is +% not a constant, it is \emph{not} settable by the programmer but is +% instead varied by \TeX{}. +% \begin{texnote} +% This is the \TeX{} primitive \cs{lastbox} renamed. +% \end{texnote} +% \end{variable} +% +% \section{Constant boxes} +% +% \begin{variable}{\c_empty_box} +% This is a permanently empty box, which is neither set as horizontal +% nor vertical. +% \end{variable} +% +% \section{Scratch boxes} +% +% \begin{variable}{\l_tmpa_tl, \l_tmpb_tl} +% Scratch boxes for local assignment. These are never used by +% the kernel code, and so are safe for use with any \LaTeX3-defined +% function. However, they may be overwritten by other non-kernel +% code and so should only be used for short-term storage. +% \end{variable} +% +% \section{Viewing box contents} +% +% \begin{function}{\box_show:N, \box_show:c} +% \begin{syntax} +% \cs{box_show:N} \meta{box} +% \end{syntax} +% Writes the contents of \meta{box} to the log file. +% \begin{texnote} +% This is the \TeX{} primitive \cs{showbox}. +% \end{texnote} +% \end{function} +% +% \section{Horizontal mode boxes} +% +% \begin{function}{\hbox:n} +% \begin{syntax} +% \cs{hbox:n} \Arg{contents} +% \end{syntax} +% Typesets the \meta{contents} into a horizontal box of natural +% width and then includes this box in the current list for typesetting. +% \begin{texnote} +% This is the \TeX{} primitive \cs{hbox}. +% \end{texnote} +% \end{function} +% +% \begin{function}{\hbox_to_wd:nn} +% \begin{syntax} +% \cs{hbox_to_wd:nn} \Arg{dimexpr} \Arg{contents} +% \end{syntax} +% Typesets the \meta{contents} into a horizontal box of width +% \meta{dimexpr} and then includes this box in the current list for +% typesetting. +% \end{function} +% +% \begin{function}{\hbox_to_zero:n} +% \begin{syntax} +% \cs{hbox_to_zero:n} \Arg{contents} +% \end{syntax} +% Typesets the \meta{contents} into a horizontal box of zero width +% and then includes this box in the current list for typesetting. +% \end{function} +% +% \begin{function}{\hbox_set:Nn, \hbox_set:cn} +% \begin{syntax} +% \cs{hbox_set:Nn} \meta{box} \Arg{contents} +% \end{syntax} +% Typesets the \meta{contents} at natural width and then stores the +% result inside the \meta{box}. The assignment is local. +% \end{function} +% +% \begin{function}{\hbox_gset:Nn, \hbox_gset:cn} +% \begin{syntax} +% \cs{hbox_gset:Nn} \meta{box} \Arg{contents} +% \end{syntax} +% Typesets the \meta{contents} at natural width and then stores the +% result inside the \meta{box}. The assignment is global. +% \end{function} +% +% \begin{function}{\hbox_set_to_wd:Nnn, \hbox_set_to_wd:cnn} +% \begin{syntax} +% \cs{hbox_set_to_wd:Nnn} \meta{box} \Arg{dimexpr} \Arg{contents} +% \end{syntax} +% Typesets the \meta{contents} to the width given by the \meta{dimexpr} +% and then stores the result inside the \meta{box}. The assignment is +% local. +% \end{function} +% +% \begin{function}{\hbox_gset_to_wd:Nnn, \hbox_gset_to_wd:cnn} +% \begin{syntax} +% \cs{hbox_gset_to_wd:Nnn} \meta{box} \Arg{dimexpr} \Arg{contents} +% \end{syntax} +% Typesets the \meta{contents} to the width given by the \meta{dimexpr} +% and then stores the result inside the \meta{box}. The assignment is +% global. +% \end{function} +% +% \begin{function}{\hbox_overlap_right:n} +% \begin{syntax} +% \cs{hbox_overlap_right:n} \Arg{contents} +% \end{syntax} +% Typesets the \meta{contents} into a horizontal box of zero width +% such that material will protrude to the right of the insertion +% point. +% \end{function} +% +% \begin{function}{\hbox_overlap_left:n} +% \begin{syntax} +% \cs{hbox_overlap_left:n} \Arg{contents} +% \end{syntax} +% Typesets the \meta{contents} into a horizontal box of zero width +% such that material will protrude to the left of the insertion +% point. +% \end{function} +% +% \begin{function} +% { +% \hbox_set_inline_begin:N, \hbox_set_inline_begin:c, +% \hbox_set_inline_end: +% } +% \begin{syntax} +% \cs{hbox_set_inline_begin:N} \meta{box} \meta{contents} +% ~~\cs{hbox_set_inline_end:} +% \end{syntax} +% Typesets the \meta{contents} at natural width and then stores the +% result inside the \meta{box}. The assignment is local. In contrast +% to \cs{hbox_set:Nn} this function does not absorb the argument +% when finding the \meta{content}, and so can be used in circumstances +% where the \meta{content} may not be a simple argument. +% \end{function} +% +% \begin{function} +% { +% \hbox_gset_inline_begin:N, \hbox_gset_inline_begin:c, +% \hbox_gset_inline_end: +% } +% \begin{syntax} +% \cs{hbox_gset_inline_begin:N} \meta{box} \meta{contents} +% ~~\cs{hbox_gset_inline_end:} +% \end{syntax} +% Typesets the \meta{contents} at natural width and then stores the +% result inside the \meta{box}. The assignment is global. In contrast +% to \cs{hbox_set:Nn} this function does not absorb the argument +% when finding the \meta{content}, and so can be used in circumstances +% where the \meta{content} may not be a simple argument. +% \end{function} +% +% \begin{function}{\hbox_unpack:N, \hbox_unpack:c} +% \begin{syntax} +% \cs{hbox_unpack:N} \meta{box} +% \end{syntax} +% Unpacks the content of the horizontal \meta{box}, retaining any stretching +% or shrinking applied when the \meta{box} was set. +% \begin{texnote} +% This is the \TeX{} primitive \cs{unhcopy}. +% \end{texnote} +% \end{function} +% +% \begin{function}{\hbox_unpack_clear:N, \hbox_unpack_clear:c} +% \begin{syntax} +% \cs{hbox_unpack_clear:N} \meta{box} +% \end{syntax} +% Unpacks the content of the horizontal \meta{box}, retaining any stretching +% or shrinking applied when the \meta{box} was set. The \meta{box} is +% then cleared globally. +% \begin{texnote} +% This is the \TeX{} primitive \cs{unhbox}. +% \end{texnote} +% \end{function} +% +% \section{Vertical mode boxes} +% +% Vertical boxes inherit their baseline from their contents. The +% standard case is that the baseline of the box is at the same position +% as that of the last item added to the box. This means that the box +% will have no depth unless the last item added to it had depth. As a +% result most vertical boxes have a large height value and small or +% zero depth. The exception are |_top| boxes, where the reference point +% is that of the first item added. These tend to have a large depth and +% small height, although the later will typically be non-zero. +% +% \begin{function}{\vbox:n} +% \begin{syntax} +% \cs{vbox:n} \Arg{contents} +% \end{syntax} +% Typesets the \meta{contents} into a vertical box of natural height +% and includes this box in the current list for typesetting. +% \begin{texnote} +% This is the \TeX{} primitive \cs{vbox}. +% \end{texnote} +% \end{function} +% +% \begin{function}{\vbox_top:n} +% \begin{syntax} +% \cs{vbox_top:n} \Arg{contents} +% \end{syntax} +% Typesets the \meta{contents} into a vertical box of natural height +% and includes this box in the current list for typesetting. The +% baseline of the box will tbe equal to that of the \emph{first} +% item added to the box. +% \begin{texnote} +% This is the \TeX{} primitive \cs{vtop}. +% \end{texnote} +% \end{function} +% +% \begin{function}{\vbox_to_ht:nn} +% \begin{syntax} +% \cs{vbox_to_ht:n} \Arg{contents} \Arg{dimexpr} +% \end{syntax} +% Typesets the \meta{contents} into a vertical box of height +% \meta{dimexpr} and then includes this box in the current list for +% typesetting. +% \end{function} +% +% \begin{function}{\vbox_to_zero:n} +% \begin{syntax} +% \cs{vbox_to_zero:n} \Arg{contents} +% \end{syntax} +% Typesets the \meta{contents} into a vertical box of zero height +% and then includes this box in the current list for typesetting. +% \end{function} +% +% \begin{function}{\vbox_set:Nn, \vbox_set:cn} +% \begin{syntax} +% \cs{vbox_set:Nn} \meta{box} \Arg{contents} +% \end{syntax} +% Typesets the \meta{contents} at natural height and then stores the +% result inside the \meta{box}. The assignment is local. +% \end{function} +% +% \begin{function}{\vbox_gset:Nn, \vbox_gset:cn} +% \begin{syntax} +% \cs{vbox_gset:Nn} \meta{box} \Arg{contents} +% \end{syntax} +% Typesets the \meta{contents} at natural height and then stores the +% result inside the \meta{box}. The assignment is global. +% \end{function} +% +% \begin{function}{\vbox_set_top:Nn, \vbox_set_top:cn} +% \begin{syntax} +% \cs{vbox_set_top:Nn} \meta{box} \Arg{contents} +% \end{syntax} +% Typesets the \meta{contents} at natural height and then stores the +% result inside the \meta{box}. The baseline of the box will tbe equal +% to that of the \emph{first} item added to the box. The assignment is +% local. +% \end{function} +% +% \begin{function}{\vbox_gset_top:Nn, \vbox_gset_top:cn} +% \begin{syntax} +% \cs{vbox_gset_top:Nn} \meta{box} \Arg{contents} +% \end{syntax} +% Typesets the \meta{contents} at natural height and then stores the +% result inside the \meta{box}. The baseline of the box will tbe equal +% to that of the \emph{first} item added to the box. The assignment is +% global. +% \end{function} +% +% \begin{function}{\vbox_set_to_ht:Nnn, \vbox_set_to_ht:cnn} +% \begin{syntax} +% \cs{vbox_set_to_ht:Nnn} \meta{box} \Arg{dimexpr} \Arg{contents} +% \end{syntax} +% Typesets the \meta{contents} to the height given by the +% \meta{dimexpr} and then stores the result inside the \meta{box}. +% The assignment is local. +% \end{function} +% +% \begin{function}{\vbox_gset_to_ht:Nnn, \vbox_gset_to_ht:cnn} +% \begin{syntax} +% \cs{vbox_gset_to_ht:Nnn} \meta{box} \Arg{dimexpr} \Arg{contents} +% \end{syntax} +% Typesets the \meta{contents} to the height given by the +% \meta{dimexpr} and then stores the result inside the \meta{box}. +% The assignment is global. +% \end{function} +% +% \begin{function} +% { +% \vbox_set_inline_begin:N, \vbox_set_inline_begin:c, +% \vbox_set_inline_end: +% } +% \begin{syntax} +% \cs{vbox_set_inline_begin:N} \meta{box} \meta{contents} +% ~~\cs{vbox_set_inline_end:} +% \end{syntax} +% Typesets the \meta{contents} at natural height and then stores the +% result inside the \meta{box}. The assignment is local. In contrast +% to \cs{vbox_set:Nn} this function does not absorb the argument +% when finding the \meta{content}, and so can be used in circumstances +% where the \meta{content} may not be a simple argument. +% \end{function} +% +% \begin{function} +% { +% \vbox_gset_inline_begin:N, \vbox_gset_inline_begin:c, +% \vbox_gset_inline_end: +% } +% \begin{syntax} +% \cs{vbox_gset_inline_begin:N} \meta{box} \meta{contents} +% ~~\cs{vbox_set_inline_end:} +% \end{syntax} +% Typesets the \meta{contents} at natural height and then stores the +% result inside the \meta{box}. The assignment is global. In contrast +% to \cs{vbox_set:Nn} this function does not absorb the argument +% when finding the \meta{content}, and so can be used in circumstances +% where the \meta{content} may not be a simple argument. +% \end{function} +% +% \begin{function}{\vbox_set_split_to_ht:NNn} +% \begin{syntax} +% \cs{vbox_set_split_to_ht:NNn} \meta{box1} \meta{box2} \Arg{dimexpr} +% \end{syntax} +% Sets \meta{box1} to contain material to the height given by the +% \meta{dimexpr} by removing content from the top of \meta{box2} +% (which must be a vertical box). +% \begin{texnote} +% This is the \TeX{} primitive \cs{vsplit}. +% \end{texnote} +% \end{function} +% +% \begin{function}{\vbox_unpack:N, \vbox_unpack:c} +% \begin{syntax} +% \cs{vbox_unpack:N} \meta{box} +% \end{syntax} +% Unpacks the content of the vertical \meta{box}, retaining any stretching +% or shrinking applied when the \meta{box} was set. +% \begin{texnote} +% This is the \TeX{} primitive \cs{unvcopy}. +% \end{texnote} +% \end{function} +% +% \begin{function}{\vbox_unpack_clear:N, \vbox_unpack_clear:c} +% \begin{syntax} +% \cs{vbox_unpack:N} \meta{box} +% \end{syntax} +% Unpacks the content of the vertical \meta{box}, retaining any stretching +% or shrinking applied when the \meta{box} was set. The \meta{box} +% is then cleared globally. +% \begin{texnote} +% This is the \TeX{} primitive \cs{unvbox}. +% \end{texnote} +% \end{function} +% +% \section{Primitive box conditionals} +% +% \begin{function}[EXP]{\if_hbox:N} +% \begin{syntax} +% \cs{if_hbox:N} \meta{box} +% ~~\meta{true code} +% \cs{else:} +% ~~\meta{false code} +% \cs{fi:} +% \end{syntax} +% Tests is \meta{box} is a horizontal box. +% \begin{texnote} +% This is the \TeX{} primitive \cs{ifhbox}. +% \end{texnote} +% \end{function} +% +% \begin{function}[EXP]{\if_vbox:N} +% \begin{syntax} +% \cs{if_vbox:N} \meta{box} +% ~~\meta{true code} +% \cs{else:} +% ~~\meta{false code} +% \cs{fi:} +% \end{syntax} +% Tests is \meta{box} is a vertical box. +% \begin{texnote} +% This is the \TeX{} primitive \cs{ifvbox}. +% \end{texnote} +% \end{function} +% +% \begin{function}[EXP]{\if_box_empty:N} +% \begin{syntax} +% \cs{if_box_empty:N} \meta{box} +% ~~\meta{true code} +% \cs{else:} +% ~~\meta{false code} +% \cs{fi:} +% \end{syntax} +% Tests is \meta{box} is an empty (void) box. +% \begin{texnote} +% This is the \TeX{} primitive \cs{ifvoid}. +% \end{texnote} +% \end{function} +% +% \end{documentation} +% +% \begin{implementation} +% +% \section{\pkg{l3box} implementation} +% +% \begin{macrocode} +%<*initex|package> +% \end{macrocode} +% +% \begin{macrocode} +%<*package> +\ProvidesExplPackage + {\ExplFileName}{\ExplFileDate}{\ExplFileVersion}{\ExplFileDescription} +\package_check_loaded_expl: +%<*initex|package> +% \end{macrocode} +% +% The code in this module is very straight forward so I'm not going to +% comment it very extensively. +% +% \subsection{Creating and initialising boxes} +% +% \TestFiles{m3box001.lvt} +% +% \begin{macro}{\box_new:N,\box_new:c} +% Defining a new \meta{box} register: remember that box $255$ is not +% generally available. +% \begin{macrocode} +%<*initex> +\alloc_new:nnnN { box } \c_zero \c_max_register_int \tex_mathchardef:D +\seq_put_right:Nn \g_box_allocation_seq {255} +%</initex> +%<*package> +\cs_new_protected:Npn \box_new:N #1 + { + \chk_if_free_cs:N #1 + \newbox #1 + } +%</package> +\cs_generate_variant:Nn \box_new:N { c } +% \end{macrocode} +% +% \begin{macro}{\box_clear:N, \box_clear:c} +% \begin{macro}{\box_gclear:N, \box_gclear:c} +% \testfile* +% Clear a \meta{box} register. +% \begin{macrocode} +\cs_new_protected_nopar:Npn \box_clear:N #1 + { \box_set_eq:NN #1 \c_empty_box } +\cs_new_protected_nopar:Npn \box_gclear:N #1 + { \box_gset_eq:NN #1 \c_empty_box } +\cs_generate_variant:Nn \box_clear:N { c } +\cs_generate_variant:Nn \box_gclear:N { c } +% \end{macrocode} +% \end{macro} +% \end{macro} +% +% \begin{macro}{\box_clear_new:N, \box_clear_new:c} +% \begin{macro}{\box_gclear_new:N, \box_gclear_new:c} +% \testfile* +% Clear or new. +% \begin{macrocode} +\cs_new_protected_nopar:Npn \box_clear_new:N #1 + { + \cs_if_exist:NTF #1 + { \box_set_eq:NN #1 \c_empty_box } + { \box_new:N #1 } + } +\cs_new_protected_nopar:Npn \box_gclear_new:N #1 + { + \cs_if_exist:NTF #1 + { \box_gset_eq:NN #1 \c_empty_box } + { \box_new:N #1 } + } +\cs_generate_variant:Nn \box_clear_new:N { c } +\cs_generate_variant:Nn \box_gclear_new:N { c } +% \end{macrocode} +% \end{macro} +% \end{macro} +% +% \begin{macro} +% {\box_set_eq:NN, \box_set_eq:cN, \box_set_eq:Nc, \box_set_eq:cc} +% \testfile* +% \begin{macro} +% {\box_gset_eq:NN, \box_gset_eq:cN, \box_gset_eq:Nc, \box_gset_eq:cc} +% \testfile* +% Assigning the contents of a box to be another box. +% \begin{macrocode} +\cs_new_protected_nopar:Npn \box_set_eq:NN #1#2 + { \tex_setbox:D #1 \tex_copy:D #2 } +\cs_new_protected_nopar:Npn \box_gset_eq:NN + { \pref_global:D \box_set_eq:NN } +\cs_generate_variant:Nn \box_set_eq:NN { cN , Nc , cc } +\cs_generate_variant:Nn \box_gset_eq:NN { cN , Nc , cc } +% \end{macrocode} +% \end{macro} +% \end{macro} +% +% \begin{macro} +% { +% \box_set_eq_clear:NN, \box_set_eq_clear:cN, +% \box_set_eq_clear:Nc, \box_set_eq_clear:cc +% } +% \testfile* +% \begin{macro} +% { +% \box_gset_eq_clear:NN, \box_gset_eq_clear:cN, +% \box_gset_eq_clear:Nc, \box_gset_eq_clear:cc +% } +% \testfile* +% Assigning the contents of a box to be another box. +% This clears the second box globally (that's how \TeX{} does it). +% \begin{macrocode} +\cs_new_protected_nopar:Npn \box_set_eq_clear:NN #1#2 + { \tex_setbox:D #1 \tex_box:D #2 } +\cs_new_protected_nopar:Npn \box_gset_eq_clear:NN + { \pref_global:D \box_set_eq_clear:NN } +\cs_generate_variant:Nn \box_set_eq_clear:NN { cN , Nc , cc } +\cs_generate_variant:Nn \box_gset_eq_clear:NN { cN , Nc , cc } +% \end{macrocode} +% \end{macro} +% \end{macro} +% +% \subsection{Measuring and setting box dimensions} +% +% \begin{macro}{\box_ht:N,\box_ht:c} +% \begin{macro}{\box_dp:N,\box_dp:c} +% \begin{macro}{\box_wd:N,\box_wd:c} +% \testfile* +% Accessing the height, depth, and width of a \meta{box} register. +% \begin{macrocode} +\cs_new_eq:NN \box_ht:N \tex_ht:D +\cs_new_eq:NN \box_dp:N \tex_dp:D +\cs_new_eq:NN \box_wd:N \tex_wd:D +\cs_generate_variant:Nn \box_ht:N { c } +\cs_generate_variant:Nn \box_dp:N { c } +\cs_generate_variant:Nn \box_wd:N { c } +% \end{macrocode} +% \end{macro} +% \end{macro} +% \end{macro} +% +% \begin{macro}{\box_set_ht:Nn, \box_set_ht:cn} +% \begin{macro}{\box_set_dp:Nn, \box_set_dp:cn} +% \begin{macro}{\box_set_wd:Nn, \box_set_wd:cn} +% Measuring is easy: all primitive work. These primitives are not +% expandable, so the derived functions are not either. +% \begin{macrocode} +\cs_new_protected_nopar:Npn \box_set_dp:Nn #1#2 + { \box_dp:N #1 \dim_eval:w #2 \dim_eval_end: } +\cs_new_protected_nopar:Npn \box_set_ht:Nn #1#2 + { \box_ht:N #1 \dim_eval:w #2 \dim_eval_end: } +\cs_new_protected_nopar:Npn \box_set_wd:Nn #1#2 + { \box_wd:N #1 \dim_eval:w #2 \dim_eval_end: } +\cs_generate_variant:Nn \box_set_ht:Nn { c } +\cs_generate_variant:Nn \box_set_dp:Nn { c } +\cs_generate_variant:Nn \box_set_wd:Nn { c } +% \end{macrocode} +% \end{macro} +% \end{macro} +% \end{macro} +% +% \subsection{Using boxes} +% +% \begin{macro}{\box_use_clear:N, \box_use_clear:c} +% \begin{macro}{\box_use:N, \box_use:c} +% Using a \meta{box}. These are just \TeX{} primitives with meaningful +% names. +% \begin{macrocode} +\cs_new_eq:NN \box_use_clear:N \tex_box:D +\cs_new_eq:NN \box_use:N \tex_copy:D +\cs_generate_variant:Nn \box_use_clear:N { c } +\cs_generate_variant:Nn \box_use:N { c } +% \end{macrocode} +% \end{macro} +% \end{macro} +% +% \begin{macro}{\box_move_left:nn,\box_move_right:nn} +% \begin{macro}{\box_move_up:nn,\box_move_down:nn} +% \testfile* +% Move box material in different directions. +% \begin{macrocode} +\cs_new_protected:Npn \box_move_left:nn #1#2 + { \tex_moveleft:D \dim_eval:w #1 \dim_eval_end: #2 } +\cs_new_protected:Npn \box_move_right:nn #1#2 + { \tex_moveright:D \dim_eval:w #1 \dim_eval_end: #2 } +\cs_new_protected:Npn \box_move_up:nn #1#2 + { \tex_raise:D \dim_eval:w #1 \dim_eval_end: #2 } +\cs_new_protected:Npn \box_move_down:nn #1#2 + { \tex_lower:D \dim_eval:w #1 \dim_eval_end: #2 } +% \end{macrocode} +% \end{macro} +% \end{macro} +% +% \subsection{Box conditionals} +% +% \begin{macro}{\if_hbox:N} +% \begin{macro}{\if_vbox:N} +% \begin{macro}{\if_box_empty:N} +% \testfile* +% The primitives for testing if a \meta{box} is empty/void or which +% type of box it is. +% \begin{macrocode} +\cs_new_eq:NN \if_hbox:N \tex_ifhbox:D +\cs_new_eq:NN \if_vbox:N \tex_ifvbox:D +\cs_new_eq:NN \if_box_empty:N \tex_ifvoid:D +% \end{macrocode} +% \end{macro} +% \end{macro} +% \end{macro} +% +% \begin{macro}[pTF]{\box_if_horizontal:N,\box_if_horizontal:c} +% \testfile* +% \begin{macro}[pTF]{\box_if_vertical:N,\box_if_vertical:c} +% \testfile* +% \begin{macrocode} +\prg_new_conditional:Npnn \box_if_horizontal:N #1 { p , T , F , TF } + { \if_hbox:N #1 \prg_return_true: \else: \prg_return_false: \fi: } +\prg_new_conditional:Npnn \box_if_vertical:N #1 { p , T , F , TF } + { \if_vbox:N #1 \prg_return_true: \else: \prg_return_false: \fi: } +\cs_generate_variant:Nn \box_if_horizontal_p:N { c } +\cs_generate_variant:Nn \box_if_horizontal:NT { c } +\cs_generate_variant:Nn \box_if_horizontal:NF { c } +\cs_generate_variant:Nn \box_if_horizontal:NTF { c } +\cs_generate_variant:Nn \box_if_vertical_p:N { c } +\cs_generate_variant:Nn \box_if_vertical:NT { c } +\cs_generate_variant:Nn \box_if_vertical:NF { c } +\cs_generate_variant:Nn \box_if_vertical:NTF { c } +% \end{macrocode} +% \end{macro} +% \end{macro} +% +% \begin{macro}[pTF]{\box_if_empty:N, \box_if_empty:c} +% \testfile* +% Testing if a \meta{box} is empty/void. +% \begin{macrocode} +\prg_new_conditional:Npnn \box_if_empty:N #1 { p , T , F , TF } + { \if_box_empty:N #1 \prg_return_true: \else: \prg_return_false: \fi: } +\cs_generate_variant:Nn \box_if_empty_p:N { c } +\cs_generate_variant:Nn \box_if_empty:NT { c } +\cs_generate_variant:Nn \box_if_empty:NF { c } +\cs_generate_variant:Nn \box_if_empty:NTF { c } +% \end{macrocode} +% \end{macro} +% \end{macro} +% +% \subsection{The last box inserted} +% +% \begin{variable}{\l_last_box} +% A different name for this read-only primitive. +% \begin{macrocode} +\cs_new_eq:NN \l_last_box \tex_lastbox:D +% \end{macrocode} +% \end{variable} +% +% \begin{macro}{\box_set_to_last:N, \box_set_to_last:c} +% \begin{macro}{\box_gset_to_last:N, \box_gset_to_last:c} +% \testfile* +% Set a box to the previous box. +% \begin{macrocode} +\cs_new_protected_nopar:Npn \box_set_to_last:N #1 + { \tex_setbox:D #1 \l_last_box } +\cs_new_protected_nopar:Npn \box_gset_to_last:N + { \pref_global:D \box_set_to_last:N } +\cs_generate_variant:Nn \box_set_to_last:N { c } +\cs_generate_variant:Nn \box_gset_to_last:N { c } +% \end{macrocode} +% \end{macro} +% \end{macro} +% +% \subsection{Constant boxes} +% +% \begin{variable}{\c_empty_box} +% \begin{macrocode} +%<*package> +\cs_new_eq:NN \c_empty_box \voidb@x +%</package> +%<*initex> +\box_new:N \c_empty_box +%</initex> +% \end{macrocode} +% \end{variable} +% +% \subsection{Scratch boxes} +% +% \begin{variable}{\l_tmpa_box, \l_tmpb_box} +% \begin{macrocode} +%<*package> +\cs_new_eq:NN \l_tmpa_box \@tempboxa +%</package> +%<*initex> +\box_new:N \l_tmpa_box +%</initex> +\box_new:N \l_tmpb_box +% \end{macrocode} +% \end{variable} +% +% \subsection{Viewing box contents} +% +% \begin{macro}{\box_show:N,\box_show:c} +% \testfile* +% Show the contents of a box and write it into the log file. +% \begin{macrocode} +\cs_new_eq:NN \box_show:N \tex_showbox:D +\cs_generate_variant:Nn \box_show:N { c } +% \end{macrocode} +% \end{macro} +% +% \subsection{Horizontal mode boxes} +% +% \begin{macro}{\hbox:n} +% \testfile{m3box002.lvt} +% Put a horizontal box directly into the input stream. +% \begin{macrocode} +\cs_new_protected_nopar:Npn \hbox:n { \tex_hbox:D \scan_stop: } +% \end{macrocode} +% \end{macro} +% +% \begin{macro}{\hbox_set:Nn,\hbox_set:cn} +% \begin{macro}{\hbox_gset:Nn,\hbox_gset:cn} +% \testfile* +% \begin{macrocode} +\cs_new_protected:Npn \hbox_set:Nn #1#2 { \tex_setbox:D #1 \tex_hbox:D {#2} } +\cs_new_protected_nopar:Npn \hbox_gset:Nn { \pref_global:D \hbox_set:Nn } +\cs_generate_variant:Nn \hbox_set:Nn { c } +\cs_generate_variant:Nn \hbox_gset:Nn { c } +% \end{macrocode} +% \end{macro} +% \end{macro} +% +% \begin{macro}{\hbox_set_to_wd:Nnn,\hbox_set_to_wd:cnn} +% \begin{macro}{\hbox_gset_to_wd:Nnn,\hbox_gset_to_wd:cnn} +% \testfile* +% Storing material in a horizontal box with a specified width. +% \begin{macrocode} +\cs_new_protected:Npn \hbox_set_to_wd:Nnn #1#2#3 + { \tex_setbox:D #1 \tex_hbox:D to \dim_eval:w #2 \dim_eval_end: {#3} } +\cs_new_protected_nopar:Npn \hbox_gset_to_wd:Nnn + { \pref_global:D \hbox_set_to_wd:Nnn } +\cs_generate_variant:Nn \hbox_set_to_wd:Nnn { c } +\cs_generate_variant:Nn \hbox_gset_to_wd:Nnn {cnn} +% \end{macrocode} +% \end{macro} +% \end{macro} +% +% \begin{macro}{\hbox_set_inline_begin:N, \hbox_set_inline_begin:c} +% \begin{macro}{\hbox_gset_inline_begin:N, \hbox_gset_inline_begin:c} +% \begin{macro}{\hbox_set_inline_end:} +% \begin{macro}{\hbox_gset_inline_end:} +% \testfile* +% Storing material in a horizontal box. This type is useful in +% environment definitions. +% \begin{macrocode} +\cs_new_protected_nopar:Npn \hbox_set_inline_begin:N #1 + { \tex_setbox:D #1 \tex_hbox:D \c_group_begin_token } +\cs_new_protected_nopar:Npn \hbox_gset_inline_begin:N + { \pref_global:D \hbox_set_inline_begin:N } +\cs_generate_variant:Nn \hbox_set_inline_begin:N { c } +\cs_generate_variant:Nn \hbox_gset_inline_begin:N { c } +\cs_new_eq:NN \hbox_set_inline_end: \c_group_end_token +\cs_new_eq:NN \hbox_gset_inline_end: \c_group_end_token +% \end{macrocode} +% \end{macro} +% \end{macro} +% \end{macro} +% \end{macro} +% +% \begin{macro}{\hbox_to_wd:nn} +% \begin{macro}{\hbox_to_zero:n} +% \testfile* +% Put a horizontal box directly into the input stream. +% \begin{macrocode} +\cs_new_protected:Npn \hbox_to_wd:nn #1#2 + { \tex_hbox:D to \dim_eval:w #1 \dim_eval_end: {#2} } +\cs_new_protected:Npn \hbox_to_zero:n #1 { \tex_hbox:D to \c_zero_skip {#1} } +% \end{macrocode} +% \end{macro} +% \end{macro} +% +% \begin{macro}{\hbox_overlap_left:n,} +% \begin{macro}{\hbox_overlap_right:n} +% Put a zero-sized box with the contents pushed against one side (which +% makes it stick out on the other) directly into the input stream. +% \begin{macrocode} +\cs_new_protected:Npn \hbox_overlap_left:n #1 + { \hbox_to_zero:n { \tex_hss:D #1 } } +\cs_new_protected:Npn \hbox_overlap_right:n #1 + { \hbox_to_zero:n { #1 \tex_hss:D } } +% \end{macrocode} +% \end{macro} +% \end{macro} +% +% \begin{macro}{\hbox_unpack:N, \hbox_unpack:c} +% \begin{macro}{\hbox_unpack_clear:N, \hbox_unpack_clear:c} +% \testfile* +% Unpacking a box and if requested also clear it. +% \begin{macrocode} +\cs_new_eq:NN \hbox_unpack:N \tex_unhcopy:D +\cs_new_eq:NN \hbox_unpack_clear:N \tex_unhbox:D +\cs_generate_variant:Nn \hbox_unpack:N { c } +\cs_generate_variant:Nn \hbox_unpack_clear:N { c } +% \end{macrocode} +% \end{macro} +% \end{macro} +% +% \subsection{Vertical mode boxes} +% +% \begin{macro}{\vbox:n} +% \TestFiles{m3box003.lvt} +% \begin{macro}{\vbox:n\vbox_top:n} +% \TestFiles{m3box003.lvt} +% Put a vertical box directly into the input stream. +% \begin{macrocode} +\cs_new_protected_nopar:Npn \vbox:n { \tex_vbox:D \scan_stop: } +\cs_new_protected_nopar:Npn \vbox_top:n { \tex_vtop:D \scan_stop: } +% \end{macrocode} +% \end{macro} +% \end{macro} +% +% \begin{macro}{\vbox_to_ht:nn,\vbox_to_zero:n} +% \begin{macro}{\vbox_to_ht:nn,\vbox_to_zero:n} +% \testfile* +% Put a vertical box directly into the input stream. +% \begin{macrocode} +\cs_new_protected:Npn \vbox_to_ht:nn #1#2 + { \tex_vbox:D to \dim_eval:w #1 \dim_eval_end: {#2} } +\cs_new_protected:Npn \vbox_to_zero:n #1 { \tex_vbox:D to \c_zero_dim {#1} } +% \end{macrocode} +% \end{macro} +% \end{macro} +% +% \begin{macro}{\vbox_set:Nn, \vbox_set:cn} +% \begin{macro}{\vbox_gset:Nn, \vbox_gset:cn} +% \testfile* +% Storing material in a vertical box with a natural height. +% \begin{macrocode} +\cs_new_protected:Npn \vbox_set:Nn #1#2 { \tex_setbox:D #1 \tex_vbox:D {#2} } +\cs_new_protected_nopar:Npn \vbox_gset:Nn { \pref_global:D \vbox_set:Nn } +\cs_generate_variant:Nn \vbox_set:Nn { c } +\cs_generate_variant:Nn \vbox_gset:Nn { c } +% \end{macrocode} +% \end{macro} +% \end{macro} +% +% \begin{macro}{\vbox_set_top:Nn, \vbox_set_top:cn} +% \begin{macro}{\vbox_gset_top:Nn, \vbox_gset_top:cn} +% \testfile* +% Storing material in a vertical box with a natural height and reference +% point at the baseline of the first object in the box. +% \begin{macrocode} +\cs_new_protected:Npn \vbox_set_top:Nn #1#2 + { \tex_setbox:D #1 \tex_vtop:D {#2} } +\cs_new_protected_nopar:Npn \vbox_gset_top:Nn + { \pref_global:D \vbox_set_top:Nn } +\cs_generate_variant:Nn \vbox_set_top:Nn { c } +\cs_generate_variant:Nn \vbox_gset_top:Nn { c } +% \end{macrocode} +% \end{macro} +% \end{macro} +% +% \begin{macro}{\vbox_set_to_ht:Nnn,\vbox_set_to_ht:cnn} +% \begin{macro}{\vbox_gset_to_ht:Nnn,\vbox_gset_to_ht:cnn} +% \testfile* +% Storing material in a vertical box with a specified height. +% \begin{macrocode} +\cs_new_protected:Npn \vbox_set_to_ht:Nnn #1#2#3 + { \tex_setbox:D #1 \tex_vbox:D to \dim_eval:w #2 \dim_eval_end: {#3} } +\cs_new_protected_nopar:Npn \vbox_gset_to_ht:Nnn + { \pref_global:D \vbox_set_to_ht:Nnn } +\cs_generate_variant:Nn \vbox_set_to_ht:Nnn { c } +\cs_generate_variant:Nn \vbox_gset_to_ht:Nnn { c } +% \end{macrocode} +% \end{macro} +% \end{macro} +% +% \begin{macro}{\vbox_set_inline_begin:N, \vbox_set_inline_begin:c} +% \begin{macro}{\vbox_gset_inline_begin:N, \vbox_gset_inline_begin:c} +% \begin{macro}{\vbox_set_inline_end:} +% \begin{macro}{\vbox_gset_inline_end:} +% \testfile* +% Storing material in a vertical box. This type is useful in +% environment definitions. +% \begin{macrocode} +\cs_new_nopar:Npn \vbox_set_inline_begin:N #1 + { \tex_setbox:D #1 \tex_vbox:D \c_group_begin_token } +\cs_new_protected_nopar:Npn \vbox_gset_inline_begin:N + { \pref_global:D \vbox_set_inline_begin:N } +\cs_generate_variant:Nn \vbox_set_inline_begin:N { c } +\cs_generate_variant:Nn \vbox_gset_inline_begin:N { c } +\cs_new_eq:NN \vbox_set_inline_end: \c_group_end_token +\cs_new_eq:NN \vbox_gset_inline_end: \c_group_end_token +% \end{macrocode} +% \end{macro} +% \end{macro} +% \end{macro} +% \end{macro} +% +% \begin{macro}{\vbox_unpack:N, \vbox_unpack:c} +% \begin{macro}{\vbox_unpack_clear:N, \vbox_unpack_clear:c} +% \testfile* +% Unpacking a box and if requested also clear it. +% \begin{macrocode} +\cs_new_eq:NN \vbox_unpack:N \tex_unvcopy:D +\cs_new_eq:NN \vbox_unpack_clear:N \tex_unvbox:D +\cs_generate_variant:Nn \vbox_unpack:N { c } +\cs_generate_variant:Nn \vbox_unpack_clear:N { c } +% \end{macrocode} +% \end{macro} +% \end{macro} +% +% \begin{macro}{\vbox_set_split_to_ht:NNn} +% \testfile* +% Splitting a vertical box in two. +% \begin{macrocode} +\cs_new_protected_nopar:Npn \vbox_set_split_to_ht:NNn #1#2#3 + { \tex_setbox:D #1 \tex_vsplit:D #2 to \dim_eval:w #3 \dim_eval_end: } +% \end{macrocode} +% \end{macro} +% +% \begin{macrocode} +%</initex|package> +% \end{macrocode} +% +% \end{implementation} +% +% \PrintIndex |