l3 (14oct15)

git-svn-id: svn://tug.org/texlive/trunk@38642 c570f23f-e606-0410-a88d-b1316a301751

8 files changed, 384 insertions, 349 deletions

diff --git a/Master/texmf-dist/source/latex/l3kernel/expl3.dtx b/Master/texmf-dist/source/latex/l3kernel/expl3.dtx
index 753aeb0ec53..42ff1e3e4f4 100644
--- a/Master/texmf-dist/source/latex/l3kernel/expl3.dtx
+++ b/Master/texmf-dist/source/latex/l3kernel/expl3.dtx
@@ -36,8 +36,8 @@
 %<*driver|generic|package>
 \def\ExplFileName{expl3}
 \def\ExplFileDescription{L3 programming layer}
-\def\ExplFileDate{2015/09/27}
-\def\ExplFileVersion{6111}
+\def\ExplFileDate{2015/10/14}
+\def\ExplFileVersion{6210}
 %</driver|generic|package>
 %<*driver>
 \documentclass[full]{l3doc}
diff --git a/Master/texmf-dist/source/latex/l3kernel/l3bootstrap.dtx b/Master/texmf-dist/source/latex/l3kernel/l3bootstrap.dtx
index 29d0a01caa8..69556596190 100644
--- a/Master/texmf-dist/source/latex/l3kernel/l3bootstrap.dtx
+++ b/Master/texmf-dist/source/latex/l3kernel/l3bootstrap.dtx
@@ -145,7 +145,7 @@
 % \end{macro}
 % \end{macro}
 % \end{macro}
-\GetIdInfo$Id: l3bootstrap.dtx 5983 2015-09-10 18:57:56Z joseph $
+\GetIdInfo$Id: l3bootstrap.dtx 6139 2015-09-30 14:02:38Z bruno $
   {L3 Bootstrap code}
 %</driver|package>
 %<*driver>
@@ -609,6 +609,7 @@
 \catcode 9   = 9\relax
 \catcode 32  = 9\relax
 \catcode 34  = 12\relax
+\catcode 38 =  4\relax
 \catcode 58  = 11\relax
 \catcode 94  = 7\relax
 \catcode 95  = 11\relax
diff --git a/Master/texmf-dist/source/latex/l3kernel/l3candidates.dtx b/Master/texmf-dist/source/latex/l3kernel/l3candidates.dtx
index 6c65d33db05..d9a3202c949 100644
--- a/Master/texmf-dist/source/latex/l3kernel/l3candidates.dtx
+++ b/Master/texmf-dist/source/latex/l3kernel/l3candidates.dtx
@@ -38,7 +38,7 @@
 \documentclass[full]{l3doc}
 %</driver>
 %<*driver|package>
-\GetIdInfo$Id: l3candidates.dtx 6039 2015-09-23 12:41:26Z joseph $
+\GetIdInfo$Id: l3candidates.dtx 6208 2015-10-09 20:01:54Z joseph $
   {L3 Experimental additions to l3kernel}
 %</driver|package>
 %<*driver>
@@ -576,6 +576,98 @@
 %
 % \section{Additions to \pkg{l3prg}}
 %
+% Minimal (lazy) evaluation can be obtained using the functions
+% \cs{bool_all_p:n}, \cs{bool_and_p:nn}, \cs{bool_any_p:n}, or
+% \cs{bool_or_p:nn}, which only evaluate their boolean expression
+% arguments when they are needed to determine the resulting truth
+% value.  For example, when evaluating the boolean expression
+% \begin{verbatim}
+%     \bool_and_p:nn
+%       {
+%         \bool_any_p:n
+%           {
+%             { \int_compare_p:n { 2 = 3 } }
+%             { \int_compare_p:n { 4 <= 4 } }
+%             { \int_compare_p:n { 1 = \error } } % is skipped
+%           }
+%       }
+%       { ! \int_compare_p:n { 2 = 4 } }
+% \end{verbatim}
+% the line marked with |is skipped| is not expanded because the result
+% of \cs{bool_any_p:n} is known once the second boolean expression is
+% found to be logically \texttt{true}.  On the other hand, the last
+% line is expanded because its logical value is needed to determine the
+% result of \cs{bool_and_p:nn}.
+%   
+% \begin{function}[EXP, added = 2015-09-28]{\bool_all_p:n}
+%   \begin{syntax}
+%     \cs{bool_all_p:n} \{ \Arg{boolexpr_1} \Arg{boolexpr_2} $\cdots$ \Arg{boolexpr_N} \}
+%   \end{syntax}
+%   Implements the \enquote{And} operation on the \meta{boolean
+%   expressions}, hence is \texttt{true} if all of them are
+%   \texttt{true} and \texttt{false} if any of them is \texttt{false}.
+%   Contrarily to the infix operator |&&|, only the \meta{boolean
+%   expressions} which are needed to determine the result of
+%   \cs{bool_all_p:n} will be evaluated.  See also \cs{bool_and_p:nn}
+%   when there are only two \meta{boolean expressions}.
+% \end{function}
+%
+% \begin{function}[EXP, added = 2015-09-28]{\bool_and_p:nn}
+%   \begin{syntax}
+%     \cs{bool_and_p:nn} \Arg{boolexpr_1} \Arg{boolexpr_2}
+%   \end{syntax}
+%   Implements the \enquote{And} operation between two boolean
+%   expressions, hence is \texttt{true} if both are \texttt{true}.
+%   Contrarily to the infix operator |&&|, the \meta{boolexpr_2} will
+%   only be evaluated if it is needed to determine the result of
+%   \cs{bool_and_p:nn}.  See also \cs{bool_all_p:n} when there are more
+%   than two \meta{boolean expressions}.
+% \end{function}
+%
+% \begin{function}[EXP, added = 2015-09-28]{\bool_any_p:n}
+%   \begin{syntax}
+%     \cs{bool_any_p:n} \{ \Arg{boolexpr_1} \Arg{boolexpr_2} $\cdots$ \Arg{boolexpr_N} \}
+%   \end{syntax}
+%   Implements the \enquote{Or} operation on the \meta{boolean
+%   expressions}, hence is \texttt{true} if any of them is
+%   \texttt{true} and \texttt{false} if all of them are \texttt{false}.
+%   Contrarily to the infix operator \verb"||", only the \meta{boolean
+%   expressions} which are needed to determine the result of
+%   \cs{bool_any_p:n} will be evaluated.  See also \cs{bool_or_p:nn}
+%   when there are only two \meta{boolean expressions}.
+% \end{function}
+%
+% \begin{function}[EXP, updated = 2012-07-08]{\bool_not_p:n}
+%   \begin{syntax}
+%      \cs{bool_not_p:n} \Arg{boolean expression}
+%   \end{syntax}
+%   Function version of |!(|\meta{boolean expression}|)| within a boolean
+%   expression.
+% \end{function}
+%
+% \begin{function}[EXP, added = 2015-09-28]{\bool_or_p:nn}
+%   \begin{syntax}
+%     \cs{bool_or_p:nn} \Arg{boolexpr_1} \Arg{boolexpr_2}
+%   \end{syntax}
+%   Implements the \enquote{Or} operation between two boolean
+%   expressions, hence is \texttt{true} if either one is \texttt{true}.
+%   Contrarily to the infix operator \verb"||", the \meta{boolexpr_2}
+%   will only be evaluated if it is needed to determine the result of
+%   \cs{bool_or_p:nn}.  See also \cs{bool_any_p:n} when there are more
+%   than two \meta{boolean expressions}.
+% \end{function}
+%
+% \begin{function}[EXP, updated = 2012-07-08]{\bool_xor_p:nn}
+%   \begin{syntax}
+%     \cs{bool_xor_p:nn} \Arg{boolexpr_1} \Arg{boolexpr_2}
+%   \end{syntax}
+%   Implements an \enquote{exclusive or} operation between two boolean
+%   expressions. There is no infix operation for this logical
+%   operator.
+% \end{function}
+%
+
+%
 % \begin{function}[added = 2014-08-22, updated = 2015-08-03]{\bool_log:N, \bool_log:c}
 %   \begin{syntax}
 %     \cs{bool_log:N} \meta{boolean}
@@ -1057,7 +1149,7 @@
 %   \end{itemize}
 %   and other values will raise an error.
 %
-%   The \meta{catcode} may be any one valid for the engine in use. Note
+%   The \meta{charcode} may be any one valid for the engine in use. Note
 %   however that for \XeTeX{} releases prior to 0.99992 only the 8-bit
 %   range ($0$ to $255$) is accepted due to engine limitations.
 % \end{function}
@@ -2484,6 +2576,86 @@
 %<@@=bool>
 %    \end{macrocode}
 %
+% \begin{macro}{\bool_all_p:n}
+% \begin{macro}[aux]{\@@_all_aux:n}
+%   Go through the list of expressions, stopping whenever an expression
+%   is \texttt{false}.  If the end is reached without finding any
+%   \texttt{false} expression, then the result is \texttt{true}.
+%    \begin{macrocode}
+\cs_new:Npn \bool_all_p:n #1
+  { \@@_all_aux:n #1 \q_recursion_tail \q_recursion_stop }
+\cs_new:Npn \@@_all_aux:n #1
+  {
+    \quark_if_recursion_tail_stop_do:nn {#1} { \c_true_bool }
+    \bool_if:nF {#1}
+      { \use_i_delimit_by_q_recursion_stop:nw { \c_false_bool } }
+    \@@_all_aux:n
+  }
+%    \end{macrocode}
+% \end{macro}
+% \end{macro}
+%
+% \begin{macro}{\bool_and_p:nn}
+%   Only evaluate the second expression if the first is \texttt{true}.
+%    \begin{macrocode}
+\cs_new:Npn \bool_and_p:nn #1#2
+  { \bool_if:nTF {#1} { \bool_if_p:n {#2} } { \c_false_bool } }
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\bool_any_p:n}
+% \begin{macro}[aux]{\@@_any_aux:n}
+%   Go through the list of expressions, stopping whenever an expression
+%   is \texttt{true}.  If the end is reached without finding any
+%   \texttt{true} expression, then the result is \texttt{false}.
+%    \begin{macrocode}
+\cs_new:Npn \bool_any_p:n #1
+  { \@@_any_aux:n #1 \q_recursion_tail \q_recursion_stop }
+\cs_new:Npn \@@_any_aux:n #1
+  {
+    \quark_if_recursion_tail_stop_do:nn {#1} { \c_false_bool }
+    \bool_if:nT {#1}
+      { \use_i_delimit_by_q_recursion_stop:nw { \c_true_bool } }
+    \@@_any_aux:n
+  }
+%    \end{macrocode}
+% \end{macro}
+% \end{macro}
+%
+% \begin{macro}{\bool_not_p:n}
+% \UnitTested
+%   The Not variant just reverses the outcome of \cs{bool_if_p:n}. Can
+%   be optimized but this is nice and simple and according to the
+%   implementation plan. Not even particularly useful to have it when
+%   the infix notation is easier to use.
+%    \begin{macrocode}
+\cs_new:Npn \bool_not_p:n #1 { \bool_if_p:n { ! ( #1 ) } }
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\bool_or_p:nn}
+%   Only evaluate the second expression if the first is \texttt{false}.
+%    \begin{macrocode}
+\cs_new:Npn \bool_or_p:nn #1#2
+  { \bool_if:nTF {#1} { \c_true_bool } { \bool_if_p:n {#2} } }
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\bool_xor_p:nn}
+% \UnitTested
+%    Exclusive or. If the boolean expressions have same truth value,
+%    return false, otherwise return true.
+%    \begin{macrocode}
+\cs_new:Npn \bool_xor_p:nn #1#2
+  {
+    \int_compare:nNnTF { \bool_if_p:n {#1} } = { \bool_if_p:n {#2} }
+      \c_false_bool
+      \c_true_bool
+  }
+%    \end{macrocode}
+% \end{macro}
+%
+%
 % \begin{macro}{\bool_log:N, \bool_log:c, \bool_log:n}
 %   Redirect output of \cs{bool_show:N} to the log.
 %    \begin{macrocode}
@@ -4418,7 +4590,8 @@
           \char_set_lccode:nn { 32 } {#1}
           \exp_args:Nx \tex_lowercase:D
             {
-              \tl_const:cn { c_@@_ \__int_to_roman:w #1 _tl }
+              \tl_const:Nn
+                \exp_not:c { c_@@_ \__int_to_roman:w #1 _tl }
                 { \exp_not:o \l_@@_tmp_tl }
             }
         }
diff --git a/Master/texmf-dist/source/latex/l3kernel/l3msg.dtx b/Master/texmf-dist/source/latex/l3kernel/l3msg.dtx
index 7ff417961b5..c4cce9a58aa 100644
--- a/Master/texmf-dist/source/latex/l3kernel/l3msg.dtx
+++ b/Master/texmf-dist/source/latex/l3kernel/l3msg.dtx
@@ -37,7 +37,7 @@
 \documentclass[full]{l3doc}
 %</driver>
 %<*driver|package>
-\GetIdInfo$Id: l3msg.dtx 6037 2015-09-23 12:41:15Z joseph $
+\GetIdInfo$Id: l3msg.dtx 6113 2015-09-28 21:30:11Z bruno $
   {L3 Messages}
 %</driver|package>
 %<*driver>
@@ -2005,31 +2005,30 @@
 %   (with category code $7$) and keep tokens until that space character,
 %   dropping everything else until \cs{q_stop}. The \cs{exp_end:} prevents
 %   losing braces around the user-inserted text if any, and stops the
-%   expansion of \cs{exp:w}.
+%   expansion of \cs{exp:w}.  One group is used to keep the settings
+%   for \tn{lowercase} local and the other one is used to prevent
+%   |\LaTeX3~error:| from being equal to \cs{scan_stop:}.
 %    \begin{macrocode}
 \group_begin:
-\char_set_catcode_math_superscript:N \^
-\char_set_lccode:nn { `^ } { `\  }
-\char_set_lccode:nn { `L } { `L }
-\char_set_lccode:nn { `T } { `T }
-\char_set_lccode:nn { `X } { `X }
-\tex_lowercase:D
+\cs_set_protected:Npn \@@_tmp:w #1#2
   {
-    \cs_new:Npx \@@_expandable_error:n #1
+    \group_end:
+    \cs_new:Npn \@@_expandable_error:n ##1
       {
-        \exp_not:n
-          {
-            \exp:w
-            \exp_after:wN \exp_after:wN
-            \exp_after:wN \@@_expandable_error:w
-            \exp_after:wN \exp_after:wN
-            \exp_after:wN \exp_end:
-          }
-        \exp_not:N \use:n { \exp_not:c { LaTeX3~error: } ^ #1 } ^
+        \exp:w
+        \exp_after:wN \exp_after:wN
+        \exp_after:wN \@@_expandable_error:w
+        \exp_after:wN \exp_after:wN
+        \exp_after:wN \exp_end:
+        \use:n { #2 #1 ##1 } #1
       }
-    \cs_new:Npn \@@_expandable_error:w #1 ^ #2 ^ { #1 }
+    \cs_new:Npn \@@_expandable_error:w ##1 #1 ##2 #1 {##1}
   }
-\group_end:
+\group_begin:
+\char_set_catcode_math_superscript:N \^
+\char_set_lccode:nn { `^ } { `\  }
+\tex_lowercase:D
+  { \group_end: \exp_args:NNc \@@_tmp:w ^ } { LaTeX3~error: }
 %    \end{macrocode}
 % \end{macro}
 % \end{macro}
diff --git a/Master/texmf-dist/source/latex/l3kernel/l3names.dtx b/Master/texmf-dist/source/latex/l3kernel/l3names.dtx
index 6b3dafbc2b3..f7d7ed4e2ee 100644
--- a/Master/texmf-dist/source/latex/l3kernel/l3names.dtx
+++ b/Master/texmf-dist/source/latex/l3kernel/l3names.dtx
@@ -37,7 +37,7 @@
 \documentclass[full]{l3doc}
 %</driver>
 %<*driver|package>
-\GetIdInfo$Id: l3names.dtx 6108 2015-09-27 08:58:42Z joseph $
+\GetIdInfo$Id: l3names.dtx 6209 2015-10-10 19:51:42Z joseph $
   {L3 Namespace for primitives}
 %</driver|package>
 %<*driver>
@@ -611,11 +611,9 @@
   \__kernel_primitive:NN \pdfoutput                 \pdftex_pdfoutput:D
   \__kernel_primitive:NN \pdfpageattr               \pdftex_pdfpageattr:D
   \__kernel_primitive:NN \pdfpagebox                \pdftex_pdfpagebox:D
-  \__kernel_primitive:NN \pdfpageheight             \pdftex_pdfpageheight:D
   \__kernel_primitive:NN \pdfpageref                \pdftex_pdfpageref:D
   \__kernel_primitive:NN \pdfpageresources          \pdftex_pdfpageresources:D
   \__kernel_primitive:NN \pdfpagesattr              \pdftex_pdfpagesattr:D
-  \__kernel_primitive:NN \pdfpagewidth              \pdftex_pdfpagewidth:D
   \__kernel_primitive:NN \pdfrefobj                 \pdftex_pdfrefobj:D
   \__kernel_primitive:NN \pdfrefxform               \pdftex_pdfrefxform:D
   \__kernel_primitive:NN \pdfrefximage              \pdftex_pdfrefximage:D
@@ -639,6 +637,8 @@
 %    \end{macrocode}
 % While these are not.
 %    \begin{macrocode}
+  \__kernel_primitive:NN \ifpdfabsdim               \pdftex_ifabsdim:D
+  \__kernel_primitive:NN \ifpdfabsnum               \pdftex_ifabsnum:D
   \__kernel_primitive:NN \ifpdfprimitive            \pdftex_ifprimitive:D
   \__kernel_primitive:NN \pdfadjustspacing          \pdftex_adjustspacing:D
   \__kernel_primitive:NN \pdfcopyfont               \pdftex_copyfont:D
@@ -657,6 +657,8 @@
   \__kernel_primitive:NN \pdfmapline                \pdftex_mapline:D
   \__kernel_primitive:NN \pdfnoligatures            \pdftex_noligatures:D
   \__kernel_primitive:NN \pdfnormaldeviate          \pdftex_normaldeviate:D
+  \__kernel_primitive:NN \pdfpageheight             \pdftex_pageheight:D
+  \__kernel_primitive:NN \pdfpagewidth              \pdftex_pagewidth:D
   \__kernel_primitive:NN \pdfpkmode                 \pdftex_pkmode:D
   \__kernel_primitive:NN \pdfpkresolution           \pdftex_pkresolution:D
   \__kernel_primitive:NN \pdfprimitive              \pdftex_primitive:D
@@ -753,9 +755,7 @@
 %    \end{macrocode}
 % Primitives from \LuaTeX{}, some of which have been ported back to
 % \XeTeX{}. Notice that \tn{expanded} was intended for \pdfTeX{}~1.50 but
-% as that was not released we call this a \LuaTeX{} primitive. Primitives
-% which are aliases are covered only once, so for example \tn{pdfpageheight}
-% covers \tn{pageheight} as well.
+% as that was not released we call this a \LuaTeX{} primitive.
 %    \begin{macrocode}
   \__kernel_primitive:NN \alignmark                 \luatex_alignmark:D
   \__kernel_primitive:NN \aligntab                  \luatex_aligntab:D
@@ -771,6 +771,7 @@
   \__kernel_primitive:NN \expanded                  \luatex_expanded:D
   \__kernel_primitive:NN \fontid                    \luatex_fontid:D
   \__kernel_primitive:NN \formatname                \luatex_formatname:D
+  \__kernel_primitive:NN \hyphenationmin            \luatex_hypenationmin:D
   \__kernel_primitive:NN \gleaders                  \luatex_gleaders:D
   \__kernel_primitive:NN \initcatcodetable          \luatex_initcatcodetable:D
   \__kernel_primitive:NN \latelua                   \luatex_latelua:D
@@ -1037,7 +1038,7 @@
 % (depending on the format-building date). There are a few primitives
 % that get the right names anyway so are missing here!
 %    \begin{macrocode}
-\etex_ifdefined:D \luatexcatcodetable
+\etex_ifdefined:D \luatexsuppressfontnotfounderror
   \tex_let:D \luatex_alignmark:D                 \luatexalignmark
   \tex_let:D \luatex_aligntab:D                  \luatexaligntab
   \tex_let:D \luatex_attribute:D                 \luatexattribute
@@ -1079,10 +1080,6 @@
 %    \begin{macrocode}
   \tex_let:D \luatex_bodydir:D               \luatexbodydir
   \tex_let:D \luatex_boxdir:D                \luatexboxdir
-  \tex_let:D \luatex_chardp:D                \luatexchardp
-  \tex_let:D \luatex_charht:D                \luatexcharht
-  \tex_let:D \luatex_charit:D                \luatexcharit
-  \tex_let:D \luatex_charwd:D                \luatexcharwd
   \tex_let:D \luatex_leftghost:D             \luatexleftghost
   \tex_let:D \luatex_localbrokenpenalty:D    \luatexlocalbrokenpenalty
   \tex_let:D \luatex_localinterlinepenalty:D \luatexlocalinterlinepenalty
@@ -1139,12 +1136,27 @@
 \tex_fi:D
 %    \end{macrocode}
 % Up to v0.80, \LuaTeX{} defines the \pdfTeX{} version data: rather
-% confusing.
+% confusing. Removing them means that \cs{pdftex_pdftexversion:D} is
+% a marker for \pdfTeX{} alone: useful in engine-dependent code later.
 %    \begin{macrocode}
 \etex_ifdefined:D \luatex_luatexversion:D
-  \tex_let:D \pdftex_pdftexbanner:D  \tex_undefined:D
-  \tex_let:D \pdftex_pdftexbanner:D  \tex_undefined:D
-  \tex_let:D \pdftex_pdftexversion:D \tex_undefined:D
+  \tex_let:D \pdftex_pdftexbanner:D   \tex_undefined:D
+  \tex_let:D \pdftex_pdftexrevision:D \tex_undefined:D
+  \tex_let:D \pdftex_pdftexversion:D  \tex_undefined:D
+\tex_fi:D
+%    \end{macrocode}
+% From v0.81, \LuaTeX{} drops the |pdf| prefix in some cases.
+%    \begin{macrocode}
+\etex_ifdefined:D \lastxpos
+  \tex_let:D \pdftex_lastxpos:D       \lastxpos
+  \tex_let:D \pdftex_lastypos:D       \lastypos
+  \tex_let:D \pdftex_normaldeviate:D  \normaldeviate
+  \tex_let:D \pdftex_pageheight:D     \pageheight
+  \tex_let:D \pdftex_pagewith:D       \pagewidth
+  \tex_let:D \pdftex_randomseed:D     \randomseed
+  \tex_let:D \pdftex_setrandomseed:D  \setrandomseed
+  \tex_let:D \pdftex_savepos:D        \savepos
+  \tex_let:D \pdftex_uniformdeviate:D \uniformdeviate
 \tex_fi:D
 %    \end{macrocode}
 %
diff --git a/Master/texmf-dist/source/latex/l3kernel/l3prg.dtx b/Master/texmf-dist/source/latex/l3kernel/l3prg.dtx
index 9acff26f534..1fc47d225b9 100644
--- a/Master/texmf-dist/source/latex/l3kernel/l3prg.dtx
+++ b/Master/texmf-dist/source/latex/l3kernel/l3prg.dtx
@@ -37,7 +37,7 @@
 \documentclass[full]{l3doc}
 %</driver>
 %<*driver|package>
-\GetIdInfo$Id: l3prg.dtx 5983 2015-09-10 18:57:56Z joseph $
+\GetIdInfo$Id: l3prg.dtx 6208 2015-10-09 20:01:54Z joseph $
   {L3 Control structures}
 %</driver|package>
 %<*driver>
@@ -72,9 +72,7 @@
 % performs a series of tests, possibly involving assignments and
 % calling other functions that do not read further ahead in the input
 % stream. After processing the input, a \emph{state} is returned. The
-% typical states returned are \meta{true} and \meta{false} but other
-% states are possible, say an \meta{error} state for erroneous
-% input, \emph{e.g.}, text as input in a function comparing integers.
+% states returned are \meta{true} and \meta{false}.
 %
 % \LaTeX3 has two forms of conditional flow processing based
 % on these states. The first form is predicate functions that turn the
@@ -87,8 +85,12 @@
 % input stream based on the result of the testing as in
 % \cs{cs_if_free:NTF} which also takes one argument (the |N|) and then
 % executes either \texttt{true} or \texttt{false} depending on the
-% result. Important to note here is that the arguments are executed
-% after exiting the underlying |\if...\fi:| structure.
+% result.
+%
+% \begin{texnote}
+%   The arguments are executed after exiting the underlying
+%   |\if...\fi:| structure.
+% \end{texnote}
 %
 % \section{Defining a set of conditional functions}
 % \label{sec:l3prg:new-conditional-functions}
@@ -140,7 +142,7 @@
 %     which will supply either a logical \texttt{true} or logical
 %     \texttt{false}. This function is intended for use in cases where
 %     one or more logical tests are combined to lead to a final outcome.
-%     This function will not work properly for \texttt{protected}
+%     This function cannot be defined for \texttt{protected}
 %     conditionals.
 %   \item \cs{\meta{name}:\meta{arg spec}T} --- a function with one more
 %     argument than the original \meta{arg spec} demands. The \meta{true
@@ -192,7 +194,7 @@
 %   \begin{syntax}
 %     \cs{prg_new_eq_conditional:NNn} \cs{\meta{name_1}:\meta{arg spec_1}} \cs{\meta{name_2}:\meta{arg spec_2}} \Arg{conditions}
 %   \end{syntax}
-%   These functions copies a family of conditionals. The \texttt{new} version
+%   These functions copy a family of conditionals. The \texttt{new} version
 %   will check for existing definitions (\emph{cf.}~\cs{cs_new:Npn}) whereas
 %   the \texttt{set} version will not (\emph{cf.}~\cs{cs_set:Npn}). The
 %   conditionals copied are depended on the comma-separated list of
@@ -208,7 +210,7 @@
 %   These `return' functions define the logical state of a conditional statement.
 %   They appear within the code for a conditional
 %   function generated by \cs{prg_set_conditional:Npnn}, \emph{etc}, to indicate
-%   when a true or false branch has been taken.
+%   when a true or false branch should be taken.
 %   While they may appear multiple times each within the code of such conditionals,
 %   the execution of the conditional must result in the expansion of one of these
 %   two functions \emph{exactly once}.
@@ -357,22 +359,23 @@
 % of predicate functions and boolean variables, return boolean
 % \meta{true} or \meta{false}. It supports the logical operations And,
 % Or and Not as the well-known infix operators |&&|, \verb"||" and |!|
-% with their usual precedences. In
+% with their usual precedences (namely, |&&| binds more tightly than
+% \verb"||"). In
 % addition to this, parentheses can be used to isolate
 % sub-expressions. For example,
 % \begin{verbatim}
 %     \int_compare_p:n { 1 = 1 } &&
 %       (
 %         \int_compare_p:n { 2 = 3 } ||
-%         \int_compare_p:n { 4 = 4 } ||
-%         \int_compare_p:n { 1 = \error } % is skipped
+%         \int_compare_p:n { 4 <= 4 } ||
+%         \str_if_eq_p:nn { abc } { def }
 %       ) &&
-%     ! ( \int_compare_p:n { 2 = 4 } )
+%     ! \int_compare_p:n { 2 = 4 }
 % \end{verbatim}
-% is a valid boolean expression. Note that minimal evaluation is
-% carried out whenever possible so that whenever a truth value cannot
-% be changed any more, the remaining tests within the current group
-% are skipped.
+% is a valid boolean expression.
+%
+% At present, the infix operators |&&| and \verb"||" perform lazy
+% evaluation as well, but this will change in a future release.
 %
 % \begin{function}[EXP, pTF, updated = 2012-07-08]{\bool_if:n}
 %   \begin{syntax}
@@ -384,45 +387,10 @@
 %   \meta{boolean expression} should consist of a series of predicates
 %   or boolean variables with the logical relationship between these
 %   defined using |&&| (\enquote{And}), \verb"||" (\enquote{Or}),
-%   |!| (\enquote{Not}) and parentheses. Minimal evaluation is used
-%   in the processing, so that once a result is defined there is
-%   not further expansion of the tests. For example
-%   \begin{verbatim}
-%     \bool_if_p:n
-%       {
-%        \int_compare_p:nNn { 1 } = { 1 }
-%        &&
-%        (
-%          \int_compare_p:nNn { 2 } = { 3 } ||
-%          \int_compare_p:nNn { 4 } = { 4 } ||
-%          \int_compare_p:nNn { 1 } = { \error } % is skipped
-%        )
-%        &&
-%        ! \int_compare_p:nNn { 2 } = { 4 }
-%     }
-%   \end{verbatim}
-%   will be \texttt{true} and will not evaluate
-%   |\int_compare_p:nNn { 1 } = { \error }|. The logical Not applies to
+%   |!| (\enquote{Not}) and parentheses.  The logical Not applies to
 %   the next predicate or group.
 % \end{function}
 %
-% \begin{function}[EXP, updated = 2012-07-08]{\bool_not_p:n}
-%   \begin{syntax}
-%      \cs{bool_not_p:n} \Arg{boolean expression}
-%   \end{syntax}
-%   Function version of |!(|\meta{boolean expression}|)| within a boolean
-%   expression.
-% \end{function}
-%
-% \begin{function}[EXP, updated = 2012-07-08]{\bool_xor_p:nn}
-%   \begin{syntax}
-%     \cs{bool_xor_p:nn} \Arg{boolexpr_1} \Arg{boolexpr_2}
-%   \end{syntax}
-%   Implements an \enquote{exclusive or} operation between two boolean
-%   expressions. There is no infix operation for this logical
-%   operator.
-% \end{function}
-%
 % \section{Logical loops}
 %
 % Loops using either boolean expressions or stored boolean values.
@@ -568,17 +536,17 @@
 %
 % \begin{function}[EXP]{\if_predicate:w}
 %   \begin{syntax}
-%     "\if_predicate:w" <predicate> <true code> "\else:" <false code> "\fi:"
+%     \cs{if_predicate:w} \meta{predicate} \meta{true code} \cs{else:} \meta{false code} \cs{fi:}
 %   \end{syntax}
 %   This function takes a predicate function and
 %   branches according to the result.  (In practice this function would also
-%   accept a single boolean variable in place of the <predicate> but to make the
-%   coding clearer this should be done through "\if_bool:N".)
+%   accept a single boolean variable in place of the \meta{predicate} but to make the
+%   coding clearer this should be done through \cs{if_bool:N}.)
 % \end{function}
 %
 % \begin{function}[EXP]{\if_bool:N}
 %   \begin{syntax}
-%     "\if_bool:N" <boolean> <true code> "\else:" <false code> "\fi:"
+%     \cs{if_bool:N} \meta{boolean} \meta{true code} \cs{else:} \meta{false code} \cs{fi:}
 %   \end{syntax}
 %   This function takes a boolean variable and
 %   branches according to the result.
@@ -664,7 +632,7 @@
 % \section{\pkg{l3prg} implementation}
 %
 % \TestFiles{m3prg001.lvt,m3prg002.lvt,m3prg003.lvt}
-%%
+%
 %    \begin{macrocode}
 %<*initex|package>
 %    \end{macrocode}
@@ -1128,7 +1096,7 @@
 % \begin{macro}[aux]+\@@_&_1:w+
 % \begin{macro}[aux]+\@@_|_0:w+
 %   Two cases where we simply continue scanning.  We must remove the
-%   second "&" or \verb"|".
+%   second |&| or \verb"|".
 %    \begin{macrocode}
 \cs_new_nopar:cpn { @@_&_1:w } & { \@@_get_next:NN \use_i:nn }
 \cs_new_nopar:cpn { @@_|_0:w } | { \@@_get_next:NN \use_i:nn }
@@ -1237,31 +1205,6 @@
 % \end{macro}
 % \end{macro}
 %
-% \begin{macro}{\bool_not_p:n}
-% \UnitTested
-%   The Not variant just reverses the outcome of \cs{bool_if_p:n}. Can
-%   be optimized but this is nice and simple and according to the
-%   implementation plan. Not even particularly useful to have it when
-%   the infix notation is easier to use.
-%    \begin{macrocode}
-\cs_new:Npn \bool_not_p:n #1 { \bool_if_p:n { ! ( #1 ) } }
-%    \end{macrocode}
-% \end{macro}
-%
-% \begin{macro}{\bool_xor_p:nn}
-% \UnitTested
-%    Exclusive or. If the boolean expressions have same truth value,
-%    return false, otherwise return true.
-%    \begin{macrocode}
-\cs_new:Npn \bool_xor_p:nn #1#2
-  {
-    \int_compare:nNnTF { \bool_if_p:n {#1} } = { \bool_if_p:n {#2} }
-      \c_false_bool
-      \c_true_bool
-  }
-%    \end{macrocode}
-% \end{macro}
-%
 % \subsection{Logical loops}
 %
 % \begin{macro}{\bool_while_do:Nn, \bool_while_do:cn}
diff --git a/Master/texmf-dist/source/latex/l3kernel/l3tl.dtx b/Master/texmf-dist/source/latex/l3kernel/l3tl.dtx
index 5ffb9ffdf33..57bfe04f3d7 100644
--- a/Master/texmf-dist/source/latex/l3kernel/l3tl.dtx
+++ b/Master/texmf-dist/source/latex/l3kernel/l3tl.dtx
@@ -37,7 +37,7 @@
 \documentclass[full]{l3doc}
 %</driver>
 %<*driver|package>
-\GetIdInfo$Id: l3tl.dtx 6037 2015-09-23 12:41:15Z joseph $
+\GetIdInfo$Id: l3tl.dtx 6121 2015-09-29 20:31:06Z bruno $
   {L3 Token lists}
 %</driver|package>
 %<*driver>
@@ -1833,14 +1833,16 @@
 %   If on the one hand it is found within the \meta{token list}, then
 %   |##1| cannot contain the \meta{delimiter}~|#1| that we worked so
 %   hard to obtain, thus \cs{@@_replace_wrap:w} gets~|##1| as its own
-%   argument~|##1|, and wraps it using \cs{exp_not:o} for consumption by
+%   argument~|##1|, and protects it against
 %   the \texttt{x}-expanding assignment.  It also finds \cs{exp_not:n}
 %   as~|##2| and does nothing to it, thus letting through \cs{exp_not:n}
-%   \Arg{replacement} into the assignment.  (Note that
+%   \Arg{replacement} into the assignment.  Note that
 %   \cs{@@_replace_next:w} and \cs{@@_replace_wrap:w} are always called
-%   followed by \cs{prg_do_nothing:} to avoid losing braces when
-%   grabbing delimited arguments, hence the use of \cs{exp_not:o} rather
-%   than \cs{exp_not:n}.)  Afterwards, \cs{@@_replace_next:w} is called
+%   followed by two empty brace groups.  These are safe because no
+%   delimiter can match them.  They prevent losing braces when grabbing
+%   delimited arguments, but require the use of \cs{exp_not:o} and
+%   \cs{use_none:nn}, rather than simply \cs{exp_not:n}.
+%   Afterwards, \cs{@@_replace_next:w} is called
 %   to repeat the replacement, or \cs{@@_replace_wrap:w} if we only want
 %   a single replacement.  In this second case, |##1| is the
 %   \meta{remaining tokens} in the \meta{token list} and |##2| is some
@@ -1850,9 +1852,9 @@
 %
 %   If on the other hand the argument~|##1| of \cs{@@_replace_next:w} is
 %   delimited by the trailing \meta{pattern}~|#5|, then |##1| is
-%   \enquote{\cs{prg_do_nothing:} \meta{token list} \meta{delimiter}
+%   \enquote{\{ \} \{ \} \meta{token list} \meta{delimiter}
 %     \Arg{ending code}}, hence \cs{@@_replace_wrap:w} finds
-%   \enquote{\cs{prg_do_nothing:} \meta{token list}} as |##1| and the
+%   \enquote{\{ \} \{ \} \meta{token list}} as |##1| and the
 %   \meta{ending code} as~|##2|.  It leaves the \meta{token list} into
 %   the assignment and unbraces the \meta{ending code} which removes
 %   what remains (essentially the \meta{delimiter} and
@@ -1861,25 +1863,27 @@
 \cs_new_protected:Npn \@@_replace_auxii:nNNNnn #1#2#3#4#5#6
   {
     \group_align_safe_begin:
-    \cs_set:Npn \@@_replace_wrap:w ##1 #1 ##2 { \exp_not:o {##1} ##2 }
+    \cs_set:Npn \@@_replace_wrap:w ##1 #1 ##2
+      { \exp_not:o { \use_none:nn ##1 } ##2 }
     \cs_set:Npx \@@_replace_next:w ##1 #5
       {
         \exp_not:N \@@_replace_wrap:w ##1
         \exp_not:n { #1 }
         \exp_not:n { \exp_not:n {#6} }
-        \exp_not:n { #2 \prg_do_nothing: }
+        \exp_not:n { #2 { } { } }
       }
     #3 #4
       {
         \exp_after:wN \@@_replace_next:w
-        \exp_after:wN \prg_do_nothing: #4
+        \exp_after:wN { \exp_after:wN }
+        \exp_after:wN { \exp_after:wN }
+        #4
         #1
         {
           \if_false: { \fi: }
           \exp_after:wN \use_none:n \exp_after:wN { \if_false: } \fi:
         }
         #5
-        \q_recursion_stop
       }
     \group_align_safe_end:
   }
diff --git a/Master/texmf-dist/source/latex/l3kernel/l3token.dtx b/Master/texmf-dist/source/latex/l3kernel/l3token.dtx
index 9699b2492eb..0075c4abfeb 100644
--- a/Master/texmf-dist/source/latex/l3kernel/l3token.dtx
+++ b/Master/texmf-dist/source/latex/l3kernel/l3token.dtx
@@ -37,7 +37,7 @@
 \documentclass[full]{l3doc}
 %</driver>
 %<*driver|package>
-\GetIdInfo$Id: l3token.dtx 6040 2015-09-23 12:41:32Z joseph $
+\GetIdInfo$Id: l3token.dtx 6114 2015-09-28 21:32:37Z bruno $
   {L3 Experimental token manipulation}
 %</driver|package>
 %<*driver>
@@ -1668,240 +1668,143 @@
 %    \end{macrocode}
 % \end{macro}
 %
+% \begin{macro}[aux]
+%   {
+%     \@@_delimit_by_char":w,
+%     \@@_delimit_by_count:w,
+%     \@@_delimit_by_dimen:w,
+%     \@@_delimit_by_macro:w,
+%     \@@_delimit_by_muskip:w,
+%     \@@_delimit_by_skip:w,
+%     \@@_delimit_by_toks:w,
+%   }
+%   These auxiliary functions are used below to define some
+%   conditionals which detect whether the \tn{meaning} of their
+%   argument begins with a particular string.  Each auxiliary takes an
+%   argument delimited by a string, a second one delimited by
+%   \cs{q_stop}, and returns the first one and its delimiter.
+%   This result will eventually be compared to another string.
+%    \begin{macrocode}
+\group_begin:
+\cs_set_protected:Npn \@@_tmp:w #1
+  {
+    \use:x
+      {
+        \cs_new:Npn \exp_not:c { @@_delimit_by_ #1 :w }
+            ####1 \tl_to_str:n {#1} ####2 \exp_not:N \q_stop
+          { ####1 \tl_to_str:n {#1} }
+      }
+  }
+\@@_tmp:w { char" }
+\@@_tmp:w { count }
+\@@_tmp:w { dimen }
+\@@_tmp:w { macro }
+\@@_tmp:w { muskip }
+\@@_tmp:w { skip }
+\@@_tmp:w { toks }
+\group_end:
+%    \end{macrocode}
+% \end{macro}
+%
 % \begin{macro}[pTF]
 %   {
 %     \token_if_chardef:N,               \token_if_mathchardef:N,
+%                                        \token_if_long_macro:N,
+%     \token_if_protected_macro:N,       \token_if_protected_long_macro:N,
 %     \token_if_dim_register:N,          \token_if_int_register:N,
 %     \token_if_muskip_register:N,
 %     \token_if_skip_register:N,         \token_if_toks_register:N,
-%                                        \token_if_long_macro:N,
-%     \token_if_protected_macro:N,       \token_if_protected_long_macro:N,
 %   }
-% \begin{macro}[aux]
-%   {
-%     \@@_if_chardef:w,
-%     \@@_if_dim_register:w,
-%     \@@_if_int_register:w,
-%     \@@_if_muskip_register:w,
-%     \@@_if_skip_register:w,
-%     \@@_if_toks_register:w,
-%     \@@_if_protected_macro:w,
-%     \@@_if_long_macro:w,
-%   }
-%   Most of these functions have to check the meaning of the token in
-%   question so we need to do some checkups on which characters are
-%   output by \cs{token_to_meaning:N}. As usual, these characters have
-%   catcode 12 so we must do some serious substitutions in the code
-%   below\dots
+%   Each of these conditionals tests whether its argument's
+%   \tn{meaning} starts with a given string.  This is essentially done
+%   by having an auxiliary grab an argument delimited by the string and
+%   testing whether the argument was empty.  Of course, a copy of this
+%   string must first be added to the end of the \tn{meaning} to avoid
+%   a runaway argument in case it does not contain the string.  Two
+%   complications arise.  First, the escape character is not fixed, and
+%   cannot be included in the delimiter of the auxiliary function (this
+%   function cannot be defined on the fly because tests must remain
+%   expandable): instead the first argument of the auxiliary (plus the
+%   delimiter to avoid complications with trailing spaces) is compared
+%   using \cs{__str_if_eq_x_return:nn} to the result of applying
+%   \cs{token_to_str:N} to a control sequence.  Second, the
+%   \tn{meaning} of primitives such as \tn{dimen} or \tn{dimendef}
+%   starts in the same way as registers such as
+%   \tn{dimen}\texttt{123}, so they must be tested for.
+%
+%   Characters used as delimiters must have catcode~$12$
+%   and are obtained through \cs{tl_to_str:n}.  This requires doing all
+%   definitions within \texttt{x}-expansion.  The temporary function
+%   \cs{@@_tmp:w} used to define each conditional receives three
+%   arguments: the name of the conditional, the auxiliary's delimiter
+%   (also used to name the auxiliary), and the string to which one
+%   compares the auxiliary's result.  Note that the \tn{meaning} of a
+%   protected long macro starts with |\protected\long macro|, with no
+%   space after |\protected| but a space after |\long|, hence the
+%   mixture of \cs{token_to_str:N} and \cs{tl_to_str:n}.
+%
+%   For the first five conditionals, \cs{cs_if_exist:cT} turns out to
+%   be \texttt{false}, and the code boils down to a string comparison
+%   between the result of the auxiliary on the \tn{meaning} of the
+%   conditional's argument~|####1|, and~|#3|.  Both are evaluated at
+%   run-time, as this is important to get the correct escape character.
+%
+%   The other five conditionals have additional code that compares the
+%   argument~|####1| to two \TeX{} primitives which would wrongly be
+%   recognized as registers otherwise.  Despite using \TeX{}'s
+%   primitive conditional construction, this does not break
+%   when~|####1| is itself a conditional, because branches of the
+%   conditionals are only skipped if |####1|~is one of the two
+%   primitives that are tested for (which are not \TeX{} conditionals).
 %    \begin{macrocode}
 \group_begin:
-  \char_set_lccode:nn { `T } { `T }
-  \char_set_lccode:nn { `F } { `F }
-  \char_set_lccode:nn { `X } { `n }
-  \char_set_lccode:nn { `Y } { `t }
-  \char_set_lccode:nn { `Z } { `d }
-  \tl_map_inline:nn { A C E G H I K L M O P R S U X Y Z R " }
-    { \char_set_catcode:nn { `#1 } \c_twelve }
-%    \end{macrocode}
-%   We convert the token list to lower case and restore the catcode and
-%   lowercase code changes.
-%    \begin{macrocode}
-\tex_lowercase:D
+\cs_set_protected:Npn \@@_tmp:w #1#2#3
   {
-    \group_end:
-%    \end{macrocode}
-%   First up is checking if something has been defined with
-%   \tn{chardef} or \tn{mathchardef}. This is easy since \TeX{}
-%   thinks of such tokens as hexadecimal so it stores them as
-%   |\char"|\meta{hex~number} or |\mathchar"|\meta{hex~number}.
-%   Grab until the first occurrence of |char"|, and compare what
-%   precedes with |\| or |\math|. In fact, the escape character
-%   may not be a backslash, so we compare with the result of
-%   converting some other control sequence to a string, namely
-%   |\char| or |\mathchar| (the auxiliary adds the |char| back).
-%    \begin{macrocode}
-    \prg_new_conditional:Npnn \token_if_chardef:N #1 { p , T ,  F , TF }
-      {
-        \__str_if_eq_x_return:nn
-          {
-            \exp_after:wN \@@_if_chardef:w
-              \token_to_meaning:N #1 CHAR" \q_stop
-          }
-          { \token_to_str:N \char }
-      }
-    \prg_new_conditional:Npnn \token_if_mathchardef:N #1 { p , T ,  F , TF }
+    \use:x
       {
-        \__str_if_eq_x_return:nn
+        \prg_new_conditional:Npnn \exp_not:c { token_if_ #1 :N } ####1
+          { p , T ,  F , TF }
           {
-            \exp_after:wN \@@_if_chardef:w
-              \token_to_meaning:N #1 CHAR" \q_stop
-          }
-          { \token_to_str:N \mathchar }
-      }
-    \cs_new:Npn \@@_if_chardef:w #1 CHAR" #2 \q_stop { #1 CHAR }
-%    \end{macrocode}
-%   Dim registers are a bit more difficult since their \tn{meaning}
-%   has the form \tn{dimen}\meta{number}, and we must take care of the
-%   two primitives \tn{dimen} and \tn{dimendef}.
-%    \begin{macrocode}
-    \prg_new_conditional:Npnn \token_if_dim_register:N #1 { p , T , F , TF }
-      {
-        \if_meaning:w \tex_dimen:D #1
-          \prg_return_false:
-        \else:
-          \if_meaning:w \tex_dimendef:D #1
-            \prg_return_false:
-          \else:
-            \__str_if_eq_x_return:nn
-              {
-                \exp_after:wN \@@_if_dim_register:w
-                  \token_to_meaning:N #1 ZIMEX \q_stop
-              }
-              { \token_to_str:N \  }
-          \fi:
-        \fi:
-      }
-    \cs_new:Npn \@@_if_dim_register:w #1 ZIMEX #2 \q_stop { #1 ~ }
-%    \end{macrocode}
-% Integer registers are one step harder since constants are implemented
-% differently from variables, and we also have to take care of the
-% primitives \tn{count} and \tn{countdef}.
-%    \begin{macrocode}
-    \prg_new_conditional:Npnn \token_if_int_register:N #1 { p , T , F , TF }
-      {
-        % \token_if_chardef:NTF #1 { \prg_return_true: }
-        %   {
-        %     \token_if_mathchardef:NTF #1 { \prg_return_true: }
-        %       {
-        \if_meaning:w \tex_count:D #1
-          \prg_return_false:
-        \else:
-          \if_meaning:w \tex_countdef:D #1
-            \prg_return_false:
-          \else:
-            \__str_if_eq_x_return:nn
-              {
-                \exp_after:wN \@@_if_int_register:w
-                  \token_to_meaning:N #1 COUXY \q_stop
-              }
-              { \token_to_str:N \  }
-          \fi:
-        \fi:
-        %       }
-        %   }
-      }
-    \cs_new:Npn \@@_if_int_register:w #1 COUXY #2 \q_stop { #1 ~ }
-%    \end{macrocode}
-%   Muskip registers are done the same way as the dimension registers.
-%    \begin{macrocode}
-    \prg_new_conditional:Npnn \token_if_muskip_register:N #1
-      { p , T , F , TF }
-      {
-        \if_meaning:w \tex_muskip:D #1
-          \prg_return_false:
-        \else:
-          \if_meaning:w \tex_muskipdef:D #1
-            \prg_return_false:
-          \else:
-            \__str_if_eq_x_return:nn
+            \cs_if_exist:cT { tex_ #2 :D }
               {
-                \exp_after:wN \@@_if_muskip_register:w
-                  \token_to_meaning:N #1 MUSKIP \q_stop
+                \exp_not:N \if_meaning:w ####1 \exp_not:c { tex_ #2 :D }
+                \exp_not:N \prg_return_false:
+                \exp_not:N \else:
+                \exp_not:N \if_meaning:w ####1 \exp_not:c { tex_ #2 def:D }
+                \exp_not:N \prg_return_false:
+                \exp_not:N \else:
               }
-              { \token_to_str:N \  }
-          \fi:
-        \fi:
-      }
-    \cs_new:Npn \@@_if_muskip_register:w #1 MUSKIP #2 \q_stop { #1 ~ }
-%    \end{macrocode}
-%   Skip registers.
-%    \begin{macrocode}
-    \prg_new_conditional:Npnn \token_if_skip_register:N #1
-      { p , T , F , TF }
-      {
-        \if_meaning:w \tex_skip:D #1
-          \prg_return_false:
-        \else:
-          \if_meaning:w \tex_skipdef:D #1
-            \prg_return_false:
-          \else:
-            \__str_if_eq_x_return:nn
+            \exp_not:N \__str_if_eq_x_return:nn
               {
-                \exp_after:wN \@@_if_skip_register:w
-                  \token_to_meaning:N #1 SKIP \q_stop
+                \exp_not:N \exp_after:wN
+                \exp_not:c { @@_delimit_by_ #2 :w }
+                \exp_not:N \token_to_meaning:N ####1
+                ? \tl_to_str:n {#2} \exp_not:N \q_stop
               }
-              { \token_to_str:N \  }
-          \fi:
-        \fi:
-      }
-    \cs_new:Npn \@@_if_skip_register:w #1 SKIP #2 \q_stop { #1 ~ }
-%    \end{macrocode}
-%   Toks registers.
-%    \begin{macrocode}
-    \prg_new_conditional:Npnn \token_if_toks_register:N #1
-      { p , T , F , TF }
-      {
-        \if_meaning:w \tex_toks:D #1
-          \prg_return_false:
-        \else:
-          \if_meaning:w \tex_toksdef:D #1
-            \prg_return_false:
-          \else:
-            \__str_if_eq_x_return:nn
+              { \exp_not:n {#3} }
+            \cs_if_exist:cT { tex_ #2 :D }
               {
-                \exp_after:wN \@@_if_toks_register:w
-                  \token_to_meaning:N #1 YOKS \q_stop
+                \exp_not:N \fi:
+                \exp_not:N \fi:
               }
-              { \token_to_str:N \  }
-          \fi:
-        \fi:
-      }
-     \cs_new:Npn \@@_if_toks_register:w #1 YOKS #2 \q_stop { #1 ~ }
-%    \end{macrocode}
-%   Protected macros.
-%    \begin{macrocode}
-    \prg_new_conditional:Npnn \token_if_protected_macro:N #1
-      { p , T ,  F , TF }
-      {
-        \__str_if_eq_x_return:nn
-          {
-            \exp_after:wN \@@_if_protected_macro:w
-              \token_to_meaning:N #1 PROYECYEZ~MACRO \q_stop
           }
-          { \token_to_str:N \  }
       }
-    \cs_new:Npn \@@_if_protected_macro:w
-      #1 PROYECYEZ~MACRO #2 \q_stop { #1 ~ }
-%    \end{macrocode}
-%   Long macros and protected long macros share an auxiliary.
-%    \begin{macrocode}
-    \prg_new_conditional:Npnn \token_if_long_macro:N #1 { p , T ,  F , TF }
-      {
-        \__str_if_eq_x_return:nn
-          {
-            \exp_after:wN \@@_if_long_macro:w
-              \token_to_meaning:N #1 LOXG~MACRO \q_stop
-          }
-          { \token_to_str:N \  }
-      }
-    \prg_new_conditional:Npnn \token_if_protected_long_macro:N #1
-      { p , T ,  F , TF }
-      {
-        \__str_if_eq_x_return:nn
-          {
-            \exp_after:wN \@@_if_long_macro:w
-              \token_to_meaning:N #1 LOXG~MACRO \q_stop
-          }
-          { \token_to_str:N \protected \token_to_str:N \  }
-      }
-    \cs_new:Npn \@@_if_long_macro:w #1 LOXG~MACRO #2 \q_stop { #1 ~ }
-%    \end{macrocode}
-% Finally the \cs{tex_lowercase:D} ends!
-%    \begin{macrocode}
   }
+\@@_tmp:w { chardef } { char" } { \token_to_str:N \char" }
+\@@_tmp:w { mathchardef } { char" } { \token_to_str:N \mathchar" }
+\@@_tmp:w { long_macro } { macro } { \tl_to_str:n { \long } macro }
+\@@_tmp:w { protected_macro } { macro }
+  { \tl_to_str:n { \protected } macro }
+\@@_tmp:w { protected_long_macro } { macro }
+  { \token_to_str:N \protected \tl_to_str:n { \long } macro }
+\@@_tmp:w { dim_register } { dimen } { \token_to_str:N \dimen }
+\@@_tmp:w { int_register } { count } { \token_to_str:N \count }
+\@@_tmp:w { muskip_register } { muskip } { \token_to_str:N \muskip }
+\@@_tmp:w { skip_register } { skip } { \token_to_str:N \skip }
+\@@_tmp:w { toks_register } { toks } { \token_to_str:N \toks }
+\group_end:
 %    \end{macrocode}
 % \end{macro}
-% \end{macro}
 %
 % \begin{macro}[pTF]{\token_if_primitive:N}
 % \begin{macro}[aux]{\@@_if_primitive:NNw,