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authorKarl Berry <karl@freefriends.org>2019-03-05 22:35:14 +0000
committerKarl Berry <karl@freefriends.org>2019-03-05 22:35:14 +0000
commit68872ff6a2a91fa0e84763fc9316493d82075c95 (patch)
tree0546ec4c414553802e31a423aec44f74d252f645 /Master/texmf-dist/source/latex/l3kernel/l3tl.dtx
parent541c4ddf7c5b402b9cfe8af5ef4e49ffa15d3e83 (diff)
l3 (5mar19)
git-svn-id: svn://tug.org/texlive/trunk@50246 c570f23f-e606-0410-a88d-b1316a301751
Diffstat (limited to 'Master/texmf-dist/source/latex/l3kernel/l3tl.dtx')
-rw-r--r--Master/texmf-dist/source/latex/l3kernel/l3tl.dtx69
1 files changed, 57 insertions, 12 deletions
diff --git a/Master/texmf-dist/source/latex/l3kernel/l3tl.dtx b/Master/texmf-dist/source/latex/l3kernel/l3tl.dtx
index 1c8867340c2..ec82eca63f0 100644
--- a/Master/texmf-dist/source/latex/l3kernel/l3tl.dtx
+++ b/Master/texmf-dist/source/latex/l3kernel/l3tl.dtx
@@ -43,7 +43,7 @@
% }^^A
% }
%
-% \date{Released 2019-02-15}
+% \date{Released 2019-03-05}
%
% \maketitle
%
@@ -700,6 +700,16 @@
% giving an \meta{integer denotation}.
% \end{function}
%
+% \begin{function}[EXP, added = 2019-02-25]{\tl_count_tokens:n}
+% \begin{syntax}
+% \cs{tl_count_tokens:n} \Arg{tokens}
+% \end{syntax}
+% Counts the number of \TeX{} tokens in the \meta{tokens} and leaves
+% this information in the input stream. Every token, including spaces and
+% braces, contributes one to the total; thus for instance, the token count of
+% |a~{bc}| is $6$.
+% \end{function}
+%
% \begin{function}[updated = 2012-01-08, EXP]
% {\tl_reverse:n, \tl_reverse:V, \tl_reverse:o}
% \begin{syntax}
@@ -822,7 +832,7 @@
% \begin{texnote}
% The result is returned within \cs{exp_not:n}, which means that the
% token list does not expand further when appearing in an
-% \texttt{x}-type argument expansion.
+% \texttt{x}-type or \texttt{e}-type argument expansion.
% \end{texnote}
% \end{function}
%
@@ -1149,7 +1159,7 @@
%
% \begin{variable}[added = 2017-11-14]{\c_novalue_tl}
% A marker for the absence of an argument. This constant |tl| can safely
-% be typeset (\emph{cf.}~|\q_nil|), with the result being |-NoValue-|.
+% be typeset (\emph{cf.}~\cs{q_nil}), with the result being |-NoValue-|.
% It is important to note that \cs{c_novalue_tl} is constructed such that it
% will \emph{not} match the simple text input |-NoValue-|, \emph{i.e.}
% that
@@ -1571,6 +1581,10 @@
%
% The two \cs{if_false:} \ldots{} \cs{fi:} are there to prevent
% alignment tabs to cause a change of tabular cell while rescanning.
+% We put the \enquote{opening} one after \cs{group_begin:} so that if
+% one accidentally \texttt{f}-expands \cs{tl_set_rescan:Nnn} braces
+% remain balanced. This is essential in \texttt{e}-type arguments
+% when \tn{expanded} is not available.
% \begin{macrocode}
\cs_new_protected:Npn \tl_set_rescan:Nnn
{ \@@_set_rescan:NNnn \tl_set:No }
@@ -1584,8 +1598,8 @@
}
\cs_new_protected:Npn \@@_set_rescan:NNnn #1#2#3#4
{
- \if_false: { \fi:
\group_begin:
+ \if_false: { \fi:
\int_set_eq:NN \tex_tracingnesting:D \c_zero_int
\exp_args:No \tex_everyeof:D { \c_@@_rescan_marker_tl }
\int_compare:nNnT \tex_endlinechar:D = { 32 }
@@ -1804,7 +1818,7 @@
% \meta{pattern}~|#6| then we can use it as the \meta{delimiter}
% through \cs{@@_replace_auxii:nNNNnn} |{#1}|. Otherwise, we end up
% calling \cs{@@_replace:NnNNNnn} repeatedly with the first two
-% arguments |\q_mark| |{?}|, |\?| |{??}|, |\??| |{???}|, and so on,
+% arguments \cs{q_mark} |{?}|, |\?| |{??}|, |\??| |{???}|, and so on,
% until |#6|~does not contain the control sequence~|#1|, which we take
% as our~\meta{A}. The argument~|#2| only serves to collect~|?|
% characters for~|#1|. Note that the order of the tests means that
@@ -2126,9 +2140,12 @@
% groups makes the test work also for empty arguments.
% The \cs{if_false:} constructions are a faster way to do
% \cs{group_align_safe_begin:} and \cs{group_align_safe_end:}.
+% The \cs{scan_stop:} ensures that \texttt{f}-expanding
+% \cs{tl_if_in:nn} does not lead to unbalanced braces.
% \begin{macrocode}
\prg_new_protected_conditional:Npnn \tl_if_in:nn #1#2 { T , F , TF }
{
+ \scan_stop:
\if_false: { \fi:
\cs_set:Npn \@@_tmp:w ##1 #2 { }
\tl_if_empty:oTF { \@@_tmp:w #1 {} {} #2 }
@@ -2427,6 +2444,36 @@
% \end{macro}
% \end{macro}
%
+%
+% \begin{macro}[EXP]{\tl_count_tokens:n}
+% \begin{macro}[EXP]{\@@_act_count_normal:nN,
+% \@@_act_count_group:nn, \@@_act_count_space:n}
+% The token count is computed through an \cs{int_eval:n} construction.
+% Each \texttt{1+} is output to the \emph{left}, into the integer
+% expression, and the sum is ended by the \cs{exp_end:} inserted by
+% \cs{@@_act_end:wn} (which is technically implemented as \cs{c_zero_int}).
+% Somewhat a hack!
+% \begin{macrocode}
+\cs_new:Npn \tl_count_tokens:n #1
+ {
+ \int_eval:n
+ {
+ \@@_act:NNNnn
+ \@@_act_count_normal:nN
+ \@@_act_count_group:nn
+ \@@_act_count_space:n
+ { }
+ {#1}
+ }
+ }
+\cs_new:Npn \@@_act_count_normal:nN #1 #2 { 1 + }
+\cs_new:Npn \@@_act_count_space:n #1 { 1 + }
+\cs_new:Npn \@@_act_count_group:nn #1 #2
+ { 2 + \tl_count_tokens:n {#2} + }
+% \end{macrocode}
+% \end{macro}
+% \end{macro}
+%
% \begin{macro}{\tl_reverse_items:n}
% \begin{macro}{\@@_reverse_items:nwNwn}
% \begin{macro}{\@@_reverse_items:wn}
@@ -2945,13 +2992,11 @@
% \end{macro}
%
% \begin{macro}[EXP,pTF]{\tl_if_head_is_group:n}
-% Pass the first token of |#1| through \cs{token_to_str:N},
-% then check for the brace balance. The extra \texttt{?}
-% caters for an empty argument.\footnote{Bruno: this could
-% be made faster, but we don't: if we hope to ever have
-% an e-type argument, we need all brace \enquote{tricks}
-% to happen in one step of expansion, keeping the token
-% list brace balanced at all times.}
+% Pass the first token of |#1| through \cs{token_to_str:N}, then check
+% for the brace balance. The extra \texttt{?} caters for an empty
+% argument. This could be made faster, but we need all brace tricks
+% to happen in one step of expansion, keeping the token list brace
+% balanced at all times.
% \begin{macrocode}
\prg_new_conditional:Npnn \tl_if_head_is_group:n #1 { p , T , F , TF }
{