[latex3-commits] [git/LaTeX3-latex3-latex3] gh900: Implement \str_map_tokens:nn (see #900) (9d3ee0fb0)

[Joseph Wright]

Repository : https://github.com/latex3/latex3
On branch  : gh900
Link       : https://github.com/latex3/latex3/commit/9d3ee0fb0ff556e601bd5d3ccc7218b4e0193aff

>---------------------------------------------------------------

commit 9d3ee0fb0ff556e601bd5d3ccc7218b4e0193aff
Author: Bruno Le Floch <blflatex at gmail.com>
Date:   Wed May 5 00:08:49 2021 +0200

    Implement \str_map_tokens:nn (see #900)


>---------------------------------------------------------------

9d3ee0fb0ff556e601bd5d3ccc7218b4e0193aff
 l3kernel/l3candidates.dtx | 39 +++++++++++++++++++++++++++++++++++++++
 l3kernel/l3str.dtx        | 10 +++++-----
 2 files changed, 44 insertions(+), 5 deletions(-)

diff --git a/l3kernel/l3candidates.dtx b/l3kernel/l3candidates.dtx
index 6cfb0d745..7e963e4eb 100644
--- a/l3kernel/l3candidates.dtx
+++ b/l3kernel/l3candidates.dtx
@@ -470,6 +470,21 @@
 %   assigned locally for |pop| or globally for |gpop| functions.
 % \end{function}
 %
+% \section{Additions to \pkg{l3str}}
+%
+% \begin{function}[rEXP, added = 2021-05-05]
+%   {\str_map_tokens:nn, \str_map_tokens:Nn, \str_map_tokens:cn}
+%   \begin{syntax}
+%     \cs{str_map_tokens:nn} \Arg{token list} \Arg{code}
+%     \cs{str_map_tokens:Nn} \meta{str~var} \Arg{code}
+%   \end{syntax}
+%   Converts the \meta{token list} to a \meta{string} then applies
+%   \meta{code} to every \meta{character} in the \meta{string} including
+%   spaces.  The \meta{code} receives each character as a trailing brace
+%   group.  This is equivalent to \cs{str_map_function:nN} if the
+%   \meta{code} consists of a single function.
+% \end{function}
+%
 % \section{Additions to \pkg{l3sys}}
 %
 % \begin{variable}[added = 2018-05-02]{\c_sys_engine_version_str}
@@ -1333,6 +1348,30 @@
 % \end{macro}
 % \end{macro}
 %
+% \subsection{Additions to \pkg{l3str}}
+%
+%    \begin{macrocode}
+%<@@=str>
+%    \end{macrocode}
+%
+% \begin{macro}[rEXP]{\str_map_tokens:Nn, \str_map_tokens:cn}
+% \begin{macro}[rEXP]{\str_map_tokens:nn}
+%   Uses an auxiliary of \cs{str_map_function:NN}.
+%    \begin{macrocode}
+\cs_new:Npn \str_map_tokens:nn #1#2
+  {
+    \exp_args:Nno \use:nn
+      { \@@_map_function:w \@@_map_function:nn {#2} }
+      { \__kernel_tl_to_str:w {#1} }
+      \q_@@_recursion_tail ? ~
+    \prg_break_point:Nn \str_map_break: { }
+  }
+\cs_new:Npn \str_map_tokens:Nn { \exp_args:No \str_map_tokens:nn }
+\cs_generate_variant:Nn \str_map_tokens:Nn { c }
+%    \end{macrocode}
+% \end{macro}
+% \end{macro}
+%
 % \subsection{Additions to \pkg{l3sys}}
 %
 %    \begin{macrocode}
diff --git a/l3kernel/l3str.dtx b/l3kernel/l3str.dtx
index 8d67927c3..9f710adae 100644
--- a/l3kernel/l3str.dtx
+++ b/l3kernel/l3str.dtx
@@ -1247,7 +1247,7 @@
 % \begin{macro}{\str_map_variable:nNn}
 % \begin{macro}{\str_map_break:}
 % \begin{macro}{\str_map_break:n}
-% \begin{macro}[rEXP]{\@@_map_function:w, \@@_map_function:Nn}
+% \begin{macro}[rEXP]{\@@_map_function:w, \@@_map_function:nn}
 % \begin{macro}{\@@_map_inline:NN, \@@_map_variable:NnN}
 %   The inline and variable mappings are similar to the usual token list
 %   mappings but start out by turning the argument to an ``other
@@ -1255,7 +1255,7 @@
 %   require \cs{__kernel_str_to_other:n}, quadratic in the string length.  To deal
 %   with spaces in that case, \cs{@@_map_function:w} replaces the
 %   following space by a braced space and a further call to itself.
-%   These are received by \cs{@@_map_function:Nn}, which passes
+%   These are received by \cs{@@_map_function:nn}, which passes
 %   the space to |#1| and calls \cs{@@_map_function:w} to deal with the
 %   next space.  The space before the braced space allows to optimize
 %   the \cs{q_@@_recursion_tail} test.  Of course we need to include a
@@ -1273,7 +1273,7 @@
 \cs_new:Npn \str_map_function:nN #1#2
   {
     \exp_after:wN \@@_map_function:w
-    \exp_after:wN \@@_map_function:Nn \exp_after:wN #2
+    \exp_after:wN \@@_map_function:nn \exp_after:wN #2
       \__kernel_tl_to_str:w {#1}
       \q_@@_recursion_tail ? ~
     \prg_break_point:Nn \str_map_break: { }
@@ -1282,12 +1282,12 @@
   { \exp_args:No \str_map_function:nN }
 \cs_new:Npn \@@_map_function:w #1 ~
   { #1 { ~ { ~ } \@@_map_function:w } }
-\cs_new:Npn \@@_map_function:Nn #1#2
+\cs_new:Npn \@@_map_function:nn #1#2
   {
     \if_meaning:w \q_@@_recursion_tail #2
       \exp_after:wN \str_map_break:
     \fi:
-    #1 #2 \@@_map_function:Nn #1
+    #1 #2 \@@_map_function:nn {#1}
   }
 \cs_generate_variant:Nn \str_map_function:NN { c }
 \cs_new_protected:Npn \str_map_inline:nn #1#2