l3 (24sep18)

git-svn-id: svn://tug.org/texlive/trunk@48749 c570f23f-e606-0410-a88d-b1316a301751

5 files changed, 224 insertions, 165 deletions

diff --git a/Master/texmf-dist/source/latex/l3packages/l3keys2e/l3keys2e.dtx b/Master/texmf-dist/source/latex/l3packages/l3keys2e/l3keys2e.dtx
index 16702af9e43..9df257daa7e 100644
--- a/Master/texmf-dist/source/latex/l3packages/l3keys2e/l3keys2e.dtx
+++ b/Master/texmf-dist/source/latex/l3packages/l3keys2e/l3keys2e.dtx
@@ -60,7 +60,7 @@
 %    }^^A
 % }
 %
-% \date{Released 2018-08-23}
+% \date{Released 2018-09-24}
 %
 % \maketitle
 %
@@ -131,7 +131,7 @@
 %    \end{macrocode}
 %
 %    \begin{macrocode}
-\ProvidesExplPackage{l3keys2e}{2018-08-23}{}
+\ProvidesExplPackage{l3keys2e}{2018-09-24}{}
   {LaTeX2e option processing using LaTeX3 keys}
 %    \end{macrocode}
 %
diff --git a/Master/texmf-dist/source/latex/l3packages/xfp/xfp.dtx b/Master/texmf-dist/source/latex/l3packages/xfp/xfp.dtx
index 9491f672954..32b7edaa0fd 100644
--- a/Master/texmf-dist/source/latex/l3packages/xfp/xfp.dtx
+++ b/Master/texmf-dist/source/latex/l3packages/xfp/xfp.dtx
@@ -62,7 +62,7 @@
 %    }^^A
 % }
 %
-% \date{Released 2018-08-23}
+% \date{Released 2018-09-24}
 %
 % \maketitle
 %
@@ -161,7 +161,7 @@
 %    \end{macrocode}
 %
 %    \begin{macrocode}
-\ProvidesExplPackage{xfp}{2018-08-23}{}
+\ProvidesExplPackage{xfp}{2018-09-24}{}
   {L3 Floating point unit}
 %    \end{macrocode}
 %
diff --git a/Master/texmf-dist/source/latex/l3packages/xfrac/xfrac.dtx b/Master/texmf-dist/source/latex/l3packages/xfrac/xfrac.dtx
index 2a1c9de876f..578c69b07c0 100644
--- a/Master/texmf-dist/source/latex/l3packages/xfrac/xfrac.dtx
+++ b/Master/texmf-dist/source/latex/l3packages/xfrac/xfrac.dtx
@@ -63,7 +63,7 @@
 %    }^^A
 % }
 %
-% \date{Released 2018-08-23}
+% \date{Released 2018-09-24}
 %
 % \maketitle
 %
@@ -533,7 +533,7 @@
 %    \end{macrocode}
 %
 %    \begin{macrocode}
-\ProvidesExplPackage{xfrac}{2018-08-23}{}
+\ProvidesExplPackage{xfrac}{2018-09-24}{}
   {L3 Experimental split-level fractions}
 %    \end{macrocode}
 %
diff --git a/Master/texmf-dist/source/latex/l3packages/xparse/xparse.dtx b/Master/texmf-dist/source/latex/l3packages/xparse/xparse.dtx
index c9685d264d5..1e24d659fe7 100644
--- a/Master/texmf-dist/source/latex/l3packages/xparse/xparse.dtx
+++ b/Master/texmf-dist/source/latex/l3packages/xparse/xparse.dtx
@@ -67,7 +67,7 @@
 %    }^^A
 % }
 %
-% \date{Released 2018-08-23}
+% \date{Released 2018-09-24}
 %
 % \maketitle
 %
@@ -818,7 +818,7 @@
 %    \end{macrocode}
 %
 %    \begin{macrocode}
-\ProvidesExplPackage{xparse}{2018-08-23}{}
+\ProvidesExplPackage{xparse}{2018-09-24}{}
   {L3 Experimental document command parser}
 %    \end{macrocode}
 %
@@ -953,6 +953,13 @@
 %    \end{macrocode}
 % \end{variable}
 %
+% \begin{variable}{\l_@@_obey_spaces_bool}
+%   For trailing optionals.
+%    \begin{macrocode}
+\bool_new:N \l_@@_obey_spaces_bool
+%    \end{macrocode}
+% \end{variable}
+%
 % \begin{variable}{\l_@@_last_delimiters_tl}
 %   Holds the delimiters (first tokens) of all optional arguments since
 %   the previous mandatory argument, to warn about cases where it would
@@ -971,13 +978,6 @@
 %    \end{macrocode}
 % \end{variable}
 %
-% \begin{variable}{\l_@@_ignore_spaces_bool}
-%   For trailing optionals.
-%    \begin{macrocode}
-\bool_new:N \l_@@_ignore_spaces_bool
-%    \end{macrocode}
-% \end{variable}
-%
 % \begin{variable}{\l_@@_m_args_int}
 %   The number of \texttt{m} arguments: if this is the same as the total
 %   number of arguments, then a short-cut can be taken in the creation of
@@ -1028,15 +1028,20 @@
 %    \end{macrocode}
 % \end{variable}
 %
-% \begin{variable}{\l_@@_some_long_bool, \l_@@_some_short_bool}
-%   Both of these flags are set while normalizing the argument
-%   specification.  To grab arguments expandably, all short arguments
-%   must appear before long arguments, so as soon as the first long
-%   argument is seen (other than \texttt{t}-type, whose long status is
-%   ignored) the \texttt{some_long} flag is set.  The
-%   \texttt{some_short} flag is used for expandable commands, to know
-%   whether to define a short auxiliary too.
-%    \begin{macrocode}
+% \begin{variable}
+%   {\l_@@_some_obey_spaces_bool, \l_@@_some_long_bool, \l_@@_some_short_bool}
+%   These flags are set while normalizing the argument specification.
+%   The \texttt{obey_spaces} one is used to detect when |!| is used on
+%   an argument that is not a trailing optional argument.
+%   The other two are used to check whether all short arguments appear
+%   before long arguments: this is needed to grab arguments expandably.
+%   As soon as the first long argument is seen (other than
+%   \texttt{t}-type, whose long status is ignored) the
+%   \texttt{some_long} flag is set.  The \texttt{some_short} flag is
+%   used for expandable commands, to know whether to define a short
+%   auxiliary too.
+%    \begin{macrocode}
+\bool_new:N \l_@@_some_obey_spaces_bool
 \bool_new:N \l_@@_some_long_bool
 \bool_new:N \l_@@_some_short_bool
 %    \end{macrocode}
@@ -1521,50 +1526,49 @@
 % specification is valid before the main parsing run.  If it is not
 % valid the entire set up is abandoned to avoid any strange internal
 % errors.  A function is provided for each argument type that will grab
-% any extra arguments and call the loop function.
-%
-% The first thing that is done in the loop is to check that the various
-% argument types have the correct number of data items associated with
-% them.  The opportunity is also taken to make sure that where a single
-% character is required, one has actually been supplied.
-%
-% The second is that processors and the marker~|+| for long arguments
-% must be followed by arguments.
-%
-% The third is to check for forbidden types for expandable commands,
-% namely \texttt{G}/\texttt{v} always, and \texttt{l}/\texttt{u} after
-% optional arguments (\pkg{xparse} may have inserted braces due to a
-% failed search for an optional argument).
-%
-% The fourth is that an optional argument should not be followed by a
-% mandatory argument with the same delimiter, as otherwise the optional
-% argument could never be omitted.
-%
-% The fifth is to keep track in \cs{l_@@_some_long_bool} and
-% \cs{l_@@_some_short_bool} of whether the command has some long/short
-% arguments.
-%
-% The sixth is to keep track in \cs{l_@@_grab_expandably_bool} of
-% whether all arguments are \texttt{m}/\texttt{l}/\texttt{u} type and
-% short arguments appear before long ones, in which case they can be
-% grabbed expandably just as safely as they could be grabbed expandably.
-% Regardless of that, arguments of expandable commands will be grabbed
-% expandably and arguments of environments will not (because the list of
-% arguments built by non-expandable grabbing is used to pass them to the
-% end-environment code).
-%
-% The last is to count mandatory arguments, used later to detect which
-% optional arguments are trailing.
+% any extra data items and call the loop function after performing the
+% following checks and tasks.
+% \begin{itemize}
+%   \item Check that each argument has the correct number of data items
+%     associated with it, and that where a single character is required,
+%     one has actually been supplied.
+%   \item Check that processors and the markers~|+| and~|!| are followed
+%     by an argument for which they make sense, and are not redundant.
+%   \item Check the absence of forbidden types for expandable commands,
+%     namely \texttt{G}/\texttt{v} always, and \texttt{l}/\texttt{u}
+%     after optional arguments (\pkg{xparse} may have inserted braces
+%     due to a failed search for an optional argument).
+%   \item Check that no optional argument is followed by a mandatory
+%     argument with the same delimiter, as otherwise the optional
+%     argument could never be omitted.
+%   \item Keep track in \cs{l_@@_some_long_bool} and
+%     \cs{l_@@_some_short_bool} of whether the command has some
+%     long/short arguments.
+%   \item Keep track in \cs{l_@@_grab_expandably_bool} of whether all
+%     arguments are \texttt{m}/\texttt{l}/\texttt{u} type and short
+%     arguments appear before long ones, in which case they can be
+%     grabbed expandably just as safely as they could be grabbed
+%     nonexpandably.  Regardless of that, arguments of expandable
+%     commands will be grabbed expandably and arguments of environments
+%     will not (because the list of arguments built by non-expandable
+%     grabbing is used to pass them to the end-environment code).
+%   \item Count mandatory arguments, used later to detect which optional
+%     arguments are trailing.
+% \end{itemize}
+% Further checks happen at the end of the loop:
+% \begin{itemize}
+% \item that there are at most $9$ arguments;
+% \item that an expandable command does not end with an optional
+%   argument (this case is detected by using the fact that
+%   \cs{l_@@_last_delimiters_tl} is cleared by every mandatory argument
+%   and filled by every optional argument).
+% \end{itemize}
 %
 % \begin{macro}{\@@_normalize_arg_spec:n}
 % \begin{macro}{\@@_normalize_arg_spec_loop:n}
 %   Loop through the argument specification, calling an auxiliary
 %   specific to each argument type.  If any argument is unknown stop the
-%   definition.  After the loop, if there are more than
-%   $9$ arguments, stop.  Additionally, expandable commands may not end
-%   with an optional argument; this case is detected by using the fact
-%   that \cs{l_@@_last_delimiters_tl} is cleared by every mandatory
-%   argument and filled by every optional argument.
+%   definition.
 %    \begin{macrocode}
 \cs_new_protected:Npn \@@_normalize_arg_spec:n #1
   {
@@ -1573,10 +1577,11 @@
     \tl_clear:N \l_@@_last_delimiters_tl
     \tl_clear:N \l_@@_arg_spec_tl
     \bool_set_true:N \l_@@_grab_expandably_bool
+    \bool_set_false:N \l_@@_obey_spaces_bool
     \bool_set_false:N \l_@@_long_bool
+    \bool_set_false:N \l_@@_some_obey_spaces_bool
     \bool_set_false:N \l_@@_some_long_bool
     \bool_set_false:N \l_@@_some_short_bool
-    \bool_set_false:N \l_@@_ignore_spaces_bool
     \@@_normalize_arg_spec_loop:n #1
       \q_recursion_tail \q_recursion_tail \q_recursion_tail \q_recursion_stop
     \int_compare:nNnT \l_@@_current_arg_int > 9
@@ -1691,7 +1696,12 @@
 \cs_new_protected:cpn { @@_normalize_type_+:w } #1
   {
     \quark_if_recursion_tail_stop_do:nn {#1} { \@@_bad_arg_spec:wn }
-    \tl_put_right:Nn \l_@@_arg_spec_tl { + }
+    \bool_if:NT \l_@@_long_bool
+      {
+        \__kernel_msg_error:nnxx { xparse } { two-markers }
+          { \iow_char:N \\ \l_@@_function_tl } { + }
+        \@@_bad_def:wn
+      }
     \bool_set_true:N \l_@@_long_bool
     \int_decr:N \l_@@_current_arg_int
     \@@_normalize_arg_spec_loop:n {#1}
@@ -1699,7 +1709,14 @@
 \cs_new_protected:cpn { @@_normalize_type_!:w } #1
   {
     \quark_if_recursion_tail_stop_do:nn {#1} { \@@_bad_arg_spec:wn }
-    \tl_put_right:Nn \l_@@_arg_spec_tl { ! }
+    \bool_if:NT \l_@@_obey_spaces_bool
+      {
+        \__kernel_msg_error:nnxx { xparse } { two-markers }
+          { \iow_char:N \\ \l_@@_function_tl } { ! }
+        \@@_bad_def:wn
+      }
+    \bool_set_true:N \l_@@_obey_spaces_bool
+    \bool_set_true:N \l_@@_some_obey_spaces_bool
     \int_decr:N \l_@@_current_arg_int
     \@@_normalize_arg_spec_loop:n {#1}
   }
@@ -1770,9 +1787,14 @@
   {
     \quark_if_recursion_tail_stop_do:Nn #1 { \@@_bad_arg_spec:wn }
     \@@_single_char_check:n {#1}
-    \tl_put_right:Nn \l_@@_arg_spec_tl { t #1 }
+    \tl_put_right:Nx \l_@@_arg_spec_tl
+      {
+        \bool_if:NT \l_@@_obey_spaces_bool { ! }
+        t \exp_not:n {#1}
+      }
     \tl_put_right:Nn \l_@@_last_delimiters_tl {#1}
     \bool_set_false:N \l_@@_grab_expandably_bool
+    \bool_set_false:N \l_@@_obey_spaces_bool
     \bool_set_false:N \l_@@_long_bool
     \@@_normalize_arg_spec_loop:n
   }
@@ -1800,17 +1822,13 @@
 \cs_new_protected:Npn \@@_normalize_type_l:w
   {
     \@@_normalize_check_lu:N l
-    \@@_add_arg_spec:n { l }
-    \int_incr:N \l_@@_mandatory_args_int
-    \tl_clear:N \l_@@_last_delimiters_tl
+    \@@_add_arg_spec_mandatory:n { l }
     \@@_normalize_arg_spec_loop:n
   }
 \cs_new_protected:Npn \@@_normalize_type_m:w
   {
     \@@_delimiter_check:nnn { } { m } { \iow_char:N \{ }
-    \@@_add_arg_spec:n { m }
-    \int_incr:N \l_@@_mandatory_args_int
-    \tl_clear:N \l_@@_last_delimiters_tl
+    \@@_add_arg_spec_mandatory:n { m }
     \@@_normalize_arg_spec_loop:n
   }
 \cs_new_protected:Npn \@@_normalize_type_R:w #1#2#3
@@ -1819,27 +1837,21 @@
     \@@_single_char_check:n {#1}
     \@@_single_char_check:n {#2}
     \@@_delimiter_check:nnn {#1} { R/r } { \tl_to_str:n {#1} }
-    \@@_add_arg_spec:n { R #1 #2 {#3} }
-    \int_incr:N \l_@@_mandatory_args_int
-    \tl_clear:N \l_@@_last_delimiters_tl
     \bool_set_false:N \l_@@_grab_expandably_bool
+    \@@_add_arg_spec_mandatory:n { R #1 #2 {#3} }
     \@@_normalize_arg_spec_loop:n
   }
 \cs_new_protected:Npn \@@_normalize_type_u:w #1
   {
     \quark_if_recursion_tail_stop_do:nn {#1} { \@@_bad_arg_spec:wn }
     \@@_normalize_check_lu:N u
-    \@@_add_arg_spec:n { u {#1} }
-    \int_incr:N \l_@@_mandatory_args_int
-    \tl_clear:N \l_@@_last_delimiters_tl
+    \@@_add_arg_spec_mandatory:n { u {#1} }
     \@@_normalize_arg_spec_loop:n
   }
 \cs_new_protected:Npn \@@_normalize_type_v:w
   {
     \@@_normalize_check_gv:N v
-    \@@_add_arg_spec:n { v }
-    \int_incr:N \l_@@_mandatory_args_int
-    \tl_clear:N \l_@@_last_delimiters_tl
+    \@@_add_arg_spec_mandatory:n { v }
     \@@_normalize_arg_spec_loop:n
   }
 %    \end{macrocode}
@@ -1936,13 +1948,16 @@
 %    \end{macrocode}
 % \end{macro}
 %
-% \begin{macro}{\@@_add_arg_spec:n}
+% \begin{macro}{\@@_add_arg_spec:n, \@@_add_arg_spec_mandatory:n}
 %   When adding an argument to the argument specification, set the
 %   \texttt{some_long} or \texttt{some_short} booleans as appropriate
-%   and clear the boolean keeping track of whether the argument is long.
+%   and clear the booleans keeping track of |+| and |!| markers.
 %   Before that, test for a short argument following some long
 %   arguments: this is forbidden for expandable commands and prevents
 %   grabbing arguments expandably.
+%
+%   For mandatory arguments do some more work, in particular complain if
+%   they were preceeded by~|!|.
 %    \begin{macrocode}
 \cs_new_protected:Npn \@@_add_arg_spec:n #1
   {
@@ -1961,8 +1976,26 @@
     \bool_if:NTF \l_@@_long_bool
       { \bool_set_true:N \l_@@_some_long_bool }
       { \bool_set_true:N \l_@@_some_short_bool }
+    \tl_put_right:Nx \l_@@_arg_spec_tl
+      {
+        \bool_if:NT \l_@@_long_bool { + }
+        \bool_if:NT \l_@@_obey_spaces_bool { ! }
+        \exp_not:n {#1}
+      }
     \bool_set_false:N \l_@@_long_bool
-    \tl_put_right:Nn \l_@@_arg_spec_tl {#1}
+    \bool_set_false:N \l_@@_obey_spaces_bool
+  }
+\cs_new_protected:Npn \@@_add_arg_spec_mandatory:n #1
+  {
+    \bool_if:NT \l_@@_some_obey_spaces_bool
+      {
+        \__kernel_msg_error:nnxx { xparse } { non-trailing-obey-spaces }
+          { \iow_char:N \\ \l_@@_function_tl } { \tl_to_str:n {#1} }
+        \@@_bad_def:wn
+      }
+    \int_incr:N \l_@@_mandatory_args_int
+    \tl_clear:N \l_@@_last_delimiters_tl
+    \@@_add_arg_spec:n {#1}
   }
 %    \end{macrocode}
 % \end{macro}
@@ -1972,8 +2005,8 @@
 % \begin{macro}{\@@_prepare_signature:n}
 % \begin{macro}{\@@_prepare_signature:N}
 % \begin{macro}{\@@_prepare_signature_bypass:N}
-%   Actually creating the signature uses the same loop approach as counting
-%   up mandatory arguments. There are first a number of variables which need
+%   Actually creating the signature uses the same loop approach as
+%   normalizing the signature. There are first a number of variables which need
 %   to be set to track what is going on. Many of these variables are unused
 %   when defining expandable commands.
 %    \begin{macrocode}
@@ -1981,7 +2014,7 @@
   {
     \int_zero:N \l_@@_current_arg_int
     \bool_set_false:N \l_@@_long_bool
-    \bool_set_false:N \l_@@_ignore_spaces_bool
+    \bool_set_false:N \l_@@_obey_spaces_bool
     \int_zero:N \l_@@_m_args_int
     \bool_set_false:N \l_@@_defaults_bool
     \tl_clear:N \l_@@_defaults_tl
@@ -2056,7 +2089,7 @@
 \cs_new_protected:cpn { @@_add_type_!:w }
   {
     \@@_flush_m_args:
-    \bool_set_true:N \l_@@_ignore_spaces_bool
+    \bool_set_true:N \l_@@_obey_spaces_bool
     \bool_set_true:N \l_@@_prefixed_bool
     \@@_prepare_signature_bypass:N
   }
@@ -2239,24 +2272,16 @@
 %
 % \begin{macro}{\@@_add_grabber_mandatory:N}
 % \begin{macro}{\@@_add_grabber_optional:N}
-%   To keep the various checks needed in one place, adding the grabber to
-%   the signature is done here. For mandatory arguments, the only question
-%   is whether to add a long grabber. For optional arguments, there is
-%   also a check to see if any mandatory arguments are still to be added.
-%   This is used to determine whether to skip spaces or not when
-%   searching for the argument.
+%   To keep the various checks needed in one place, adding the grabber
+%   to the signature is done here.  The only questions are whether the
+%   grabber should be long or not, and whether to obey spaces.  The
+%   \cs{l_@@_obey_spaces_bool} boolean can only be \texttt{true} for
+%   trailing optional arguments.  In that case spaces will not be
+%   ignored when looking for that optional argument.
 %    \begin{macrocode}
 \cs_new_protected:Npn \@@_add_grabber_mandatory:N #1
   {
-    \tl_put_right:Nx \l_@@_signature_tl
-      {
-        \exp_not:c
-          { @@_grab_ #1 \bool_if:NT \l_@@_long_bool { _long } :w }
-      }
-    \bool_set_false:N \l_@@_long_bool
-    \tl_put_right:Nx \l_@@_process_all_tl
-      { { \exp_not:o \l_@@_process_one_tl } }
-    \tl_clear:N \l_@@_process_one_tl
+    \@@_add_grabber_optional:N #1
     \int_decr:N \l_@@_mandatory_args_int
   }
 \cs_new_protected:Npn \@@_add_grabber_optional:N #1
@@ -2267,15 +2292,12 @@
           {
             @@_grab_ #1
             \bool_if:NT \l_@@_long_bool { _long }
-            \bool_lazy_and:nnT
-              { \l_@@_ignore_spaces_bool }
-              { \int_compare_p:nNn \l_@@_mandatory_args_int = 0 }
-              { _ignore_spaces }
+            \bool_if:NT \l_@@_obey_spaces_bool { _obey_spaces }
             :w
           }
       }
     \bool_set_false:N \l_@@_long_bool
-    \bool_set_false:N \l_@@_ignore_spaces_bool
+    \bool_set_false:N \l_@@_obey_spaces_bool
     \tl_put_right:Nx \l_@@_process_all_tl
       { { \exp_not:o \l_@@_process_one_tl } }
     \tl_clear:N \l_@@_process_one_tl
@@ -2573,28 +2595,34 @@
 %
 % \begin{macro}{\@@_grab_D:w}
 % \begin{macro}{\@@_grab_D_long:w}
-% \begin{macro}{\@@_grab_D_ignore_spaces:w}
-% \begin{macro}{\@@_grab_D_long_ignore_spaces:w}
+% \begin{macro}{\@@_grab_D_obey_spaces:w}
+% \begin{macro}{\@@_grab_D_long_obey_spaces:w}
 %   The generic delimited argument grabber. The auxiliary function does
 %   a peek test before calling \cs{@@_grab_D_call:Nw}, so that the
 %   optional nature of the argument works as expected.
 %    \begin{macrocode}
 \cs_new_protected:Npn \@@_grab_D:w #1#2#3 \@@_run_code:
   {
-    \@@_grab_D_aux:NNnNn #1 #2 {#3} \cs_set_protected_nopar:Npn
-      { _ignore_spaces }
+    \@@_grab_D_aux:NNnNN #1 #2 {#3} \cs_set_protected_nopar:Npn
+      \@@_peek_nonspace_remove:NTF
   }
 \cs_new_protected:Npn \@@_grab_D_long:w #1#2#3 \@@_run_code:
   {
-    \@@_grab_D_aux:NNnNn #1 #2 {#3} \cs_set_protected:Npn
-      { _ignore_spaces }
+    \@@_grab_D_aux:NNnNN #1 #2 {#3} \cs_set_protected:Npn
+      \@@_peek_nonspace_remove:NTF
+  }
+\cs_new_protected:Npn \@@_grab_D_obey_spaces:w #1#2#3 \@@_run_code:
+  {
+    \@@_grab_D_aux:NNnNN #1 #2 {#3} \cs_set_protected_nopar:Npn
+      \peek_meaning_remove:NTF
+  }
+\cs_new_protected:Npn \@@_grab_D_long_obey_spaces:w #1#2#3 \@@_run_code:
+  {
+    \@@_grab_D_aux:NNnNN #1 #2 {#3} \cs_set_protected:Npn
+      \peek_meaning_remove:NTF
   }
-\cs_new_protected:Npn \@@_grab_D_ignore_spaces:w #1#2#3 \@@_run_code:
-  { \@@_grab_D_aux:NNnNn #1 #2 {#3} \cs_set_protected_nopar:Npn { } }
-\cs_new_protected:Npn \@@_grab_D_long_ignore_spaces:w #1#2#3 \@@_run_code:
-  { \@@_grab_D_aux:NNnNn #1 #2 {#3} \cs_set_protected:Npn { } }
 %    \end{macrocode}
-% \begin{macro}{\@@_grab_D_aux:NNnNn}
+% \begin{macro}{\@@_grab_D_aux:NNnNN}
 % \begin{macro}{\@@_grab_D_aux:NNnN}
 %   This is a bit complicated. The idea is that, in order to check for
 %   nested optional argument tokens (\texttt{[[...]]} and so on) the
@@ -2604,10 +2632,10 @@
 %   prevents loss of braces, and there is then a test to see if there are
 %   nested delimiters to handle.
 %    \begin{macrocode}
-\cs_new_protected:Npn \@@_grab_D_aux:NNnNn #1#2#3#4#5
+\cs_new_protected:Npn \@@_grab_D_aux:NNnNN #1#2#3#4#5
   {
     \@@_grab_D_aux:NNnN #1#2 {#3} #4
-    \use:c { peek_meaning_remove #5 :NTF } #1
+    #5 #1
       { \@@_grab_D_call:Nw #1 }
       { \@@_add_arg:o \c_novalue_tl }
   }
@@ -2743,36 +2771,36 @@
 % \begin{macro}
 %   {
 %     \@@_grab_E:w, \@@_grab_E_long:w,
-%     \@@_grab_E_ignore_spaces:w, \@@_grab_E_long_ignore_spaces:w
+%     \@@_grab_E_obey_spaces:w, \@@_grab_E_long_obey_spaces:w
 %   }
-% \begin{macro}{\@@_grab_E:nnNn}
-% \begin{macro}{\@@_grab_E_loop:nnN}
+% \begin{macro}{\@@_grab_E:nnNN}
+% \begin{macro}{\@@_grab_E_loop:NnN}
 % \begin{macro}{\@@_grab_E_finalise:}
 %   Everything here needs to point to a loop.
 %    \begin{macrocode}
 \cs_new_protected:Npn \@@_grab_E:w #1#2 \@@_run_code:
   {
-    \@@_grab_E:nnNn {#1} {#2}
+    \@@_grab_E:nnNN {#1} {#2}
       \cs_set_protected_nopar:Npn
-      { _ignore_spaces }
+      \@@_peek_nonspace_remove:NTF
   }
 \cs_new_protected:Npn \@@_grab_E_long:w #1#2 \@@_run_code:
   {
-    \@@_grab_E:nnNn {#1} {#2}
+    \@@_grab_E:nnNN {#1} {#2}
       \cs_set_protected:Npn
-      { _ignore_spaces }
+      \@@_peek_nonspace_remove:NTF
   }
-\cs_new_protected:Npn \@@_grab_E_ignore_spaces:w #1#2 \@@_run_code:
+\cs_new_protected:Npn \@@_grab_E_obey_spaces:w #1#2 \@@_run_code:
   {
-    \@@_grab_E:nnNn {#1} {#2}
+    \@@_grab_E:nnNN {#1} {#2}
       \cs_set_protected_nopar:Npn
-      { }
+      \peek_meaning_remove:NTF
   }
-\cs_new_protected:Npn \@@_grab_E_long_ignore_spaces:w #1#2 \@@_run_code:
+\cs_new_protected:Npn \@@_grab_E_long_obey_spaces:w #1#2 \@@_run_code:
   {
-    \@@_grab_E:nnNn {#1} {#2}
+    \@@_grab_E:nnNN {#1} {#2}
       \cs_set_protected:Npn
-      { }
+      \peek_meaning_remove:NTF
   }
 %    \end{macrocode}
 %   A loop is needed here to allow a random ordering of keys. These are
@@ -2780,12 +2808,12 @@
 %   they can appear later. The grabbed values are held in a property list
 %   which is then turned into an ordered list to be passed back to the user.
 %    \begin{macrocode}
-\cs_new_protected:Npn \@@_grab_E:nnNn #1#2#3#4
+\cs_new_protected:Npn \@@_grab_E:nnNN #1#2#3#4
   {
     \exp_after:wN #3 \l_@@_fn_tl ##1##2##3
       {
         \prop_put:Nnn \l_@@_tmp_prop {##1} {##3}
-        \@@_grab_E_loop:nnN {#4} { } ##2 \q_recursion_stop
+        \@@_grab_E_loop:NnN #4 { } ##2 \q_recursion_stop
       }
     \prop_clear:N \l_@@_tmp_prop
     \tl_set:Nn \l_@@_signature_tl {#2}
@@ -2800,16 +2828,16 @@
           }
         \l_@@_signature_tl \@@_run_code:
       }
-    \@@_grab_E_loop:nnN {#4} { } #1 \q_recursion_tail \q_recursion_stop
+    \@@_grab_E_loop:NnN #4 { } #1 \q_recursion_tail \q_recursion_stop
   }
-\cs_new_protected:Npn \@@_grab_E_loop:nnN #1#2#3#4 \q_recursion_stop
+\cs_new_protected:Npn \@@_grab_E_loop:NnN #1#2#3#4 \q_recursion_stop
   {
     \cs_if_eq:NNTF #3 \q_recursion_tail
       { \@@_grab_E_finalise: }
       {
-        \use:c { peek_meaning_remove #1 :NTF } #3
+        #1 #3
           { \l_@@_fn_tl #3 {#2#4} }
-          { \@@_grab_E_loop:nnN {#1} {#2#3} #4 \q_recursion_stop }
+          { \@@_grab_E_loop:NnN #1 {#2#3} #4 \q_recursion_stop }
       }
   }
 \cs_new_protected:Npn \@@_grab_E_finalise: { }
@@ -2821,31 +2849,38 @@
 %
 % \begin{macro}{\@@_grab_G:w}
 % \begin{macro}{\@@_grab_G_long:w}
-% \begin{macro}{\@@_grab_G_ignore_spaces:w}
-% \begin{macro}{\@@_grab_G_long_ignore_spaces:w}
-% \begin{macro}{\@@_grab_G_aux:nNn}
+% \begin{macro}{\@@_grab_G_obey_spaces:w}
+% \begin{macro}{\@@_grab_G_long_obey_spaces:w}
+% \begin{macro}{\@@_grab_G_aux:nNN}
 %   Optional groups are checked by meaning, so that the same code will
 %   work with, for example, \ConTeXt{}-like input.
 %    \begin{macrocode}
 \cs_new_protected:Npn \@@_grab_G:w #1 \@@_run_code:
   {
-    \@@_grab_G_aux:nNn {#1} \cs_set_protected_nopar:Npn
-      { _ignore_spaces }
+    \@@_grab_G_aux:nNN {#1} \cs_set_protected_nopar:Npn
+      \@@_peek_nonspace:NTF
   }
 \cs_new_protected:Npn \@@_grab_G_long:w #1 \@@_run_code:
   {
-    \@@_grab_G_aux:nNn {#1} \cs_set_protected:Npn { _ignore_spaces }
+    \@@_grab_G_aux:nNN {#1} \cs_set_protected:Npn
+      \@@_peek_nonspace:NTF
+  }
+\cs_new_protected:Npn \@@_grab_G_obey_spaces:w #1 \@@_run_code:
+  {
+    \@@_grab_G_aux:nNN {#1} \cs_set_protected_nopar:Npn
+      \peek_meaning:NTF
   }
-\cs_new_protected:Npn \@@_grab_G_ignore_spaces:w #1 \@@_run_code:
-  { \@@_grab_G_aux:nNn {#1} \cs_set_protected_nopar:Npn { } }
-\cs_new_protected:Npn \@@_grab_G_long_ignore_spaces:w #1 \@@_run_code:
-  { \@@_grab_G_aux:nNn {#1} \cs_set_protected:Npn { } }
-\cs_new_protected:Npn \@@_grab_G_aux:nNn #1#2#3
+\cs_new_protected:Npn \@@_grab_G_long_obey_spaces:w #1 \@@_run_code:
+  {
+    \@@_grab_G_aux:nNN {#1} \cs_set_protected:Npn
+      \peek_meaning:NTF
+  }
+\cs_new_protected:Npn \@@_grab_G_aux:nNN #1#2#3
   {
     \tl_set:Nn \l_@@_signature_tl {#1}
     \exp_after:wN #2 \l_@@_fn_tl ##1
       { \@@_add_arg:n {##1} }
-    \use:c { peek_meaning #3 :NTF } \c_group_begin_token
+    #3 \c_group_begin_token
       { \l_@@_fn_tl }
       { \@@_add_arg:o \c_novalue_tl }
   }
@@ -2998,7 +3033,7 @@
 \cs_new_protected:Npn \@@_grab_R_aux:NNnN #1#2#3#4
   {
     \@@_grab_D_aux:NNnN #1 #2 {#3} #4
-    \peek_meaning_remove_ignore_spaces:NTF #1
+    \@@_peek_nonspace_remove:NTF #1
       { \@@_grab_D_call:Nw #1 }
       {
         \__kernel_msg_error:nnxx { xparse } { missing-required }
@@ -3012,19 +3047,15 @@
 % \end{macro}
 %
 % \begin{macro}{\@@_grab_t:w}
-% \begin{macro}{\@@_grab_t_long:w}
-% \begin{macro}{\@@_grab_t_ignore_spaces:w}
-% \begin{macro}{\@@_grab_t_long_ignore_spaces:w}
+% \begin{macro}{\@@_grab_t_obey_spaces:w}
 % \begin{macro}{\@@_grab_t_aux:NNw}
 %   Dealing with a token is quite easy. Check the match, remove the
 %   token if needed and add a flag to the output.
 %    \begin{macrocode}
 \cs_new_protected:Npn \@@_grab_t:w
-  { \@@_grab_t_aux:NNw \peek_meaning_remove_ignore_spaces:NTF }
-\cs_new_eq:NN \@@_grab_t_long:w \@@_grab_t:w
-\cs_new_protected:Npn \@@_grab_t_ignore_spaces:w
+  { \@@_grab_t_aux:NNw \@@_peek_nonspace_remove:NTF }
+\cs_new_protected:Npn \@@_grab_t_obey_spaces:w
   { \@@_grab_t_aux:NNw \peek_meaning_remove:NTF }
-\cs_new_eq:NN \@@_grab_t_long_ignore_spaces:w \@@_grab_t_ignore_spaces:w
 \cs_new_protected:Npn \@@_grab_t_aux:NNw #1#2#3 \@@_run_code:
   {
     \tl_set:Nn \l_@@_signature_tl {#3}
@@ -3040,8 +3071,6 @@
 % \end{macro}
 % \end{macro}
 % \end{macro}
-% \end{macro}
-% \end{macro}
 %
 % \begin{macro}{\@@_grab_u:w}
 % \begin{macro}{\@@_grab_u_long:w}
@@ -4066,6 +4095,23 @@
 % \end{macro}
 % \end{macro}
 %
+% \begin{macro}{\@@_peek_nonspace:NTF, \@@_peek_nonspace_remove:NTF, \@@_peek_nonspace_aux:nNNTF}
+%   Collect spaces in a loop, and put the collected spaces back in the
+%   false branch of a call to \cs{peek_meaning:NTF} or
+%   \cs{peek_meaning_remove:NTF}.
+%    \begin{macrocode}
+\cs_new_protected:Npn \@@_peek_nonspace:NTF
+  { \@@_peek_nonspace_aux:nNNTF { } \peek_meaning:NTF }
+\cs_new_protected:Npn \@@_peek_nonspace_remove:NTF
+  { \@@_peek_nonspace_aux:nNNTF { } \peek_meaning_remove:NTF }
+\cs_new_protected:Npn \@@_peek_nonspace_aux:nNNTF #1#2#3#4#5
+  {
+    \peek_meaning_remove:NTF \c_space_token
+      { \@@_peek_nonspace_aux:nNNTF { #1 ~ } #2 #3 {#4} {#5} }
+      { #2 #3 { #4 } { #5 #1 } }
+  }
+% \end{macro}
+%
 % \subsection{Messages}
 %
 % Some messages intended as errors.
@@ -4158,6 +4204,13 @@
     The~current~command~'#1'~expects~an~argument~starting~with~'#2'.~
     LaTeX~did~not~find~it,~and~will~insert~a~default~value~to~be~processed.
   }
+\__kernel_msg_new:nnnn { xparse } { non-trailing-obey-spaces }
+  { Prefix~'!'~used~before~mandatory~argument~'#2'~of~command~'#1'. }
+  {
+    The~prefix~'!'~can~only~apply~to~trailing~optional~arguments.
+    \\ \\
+    LaTeX~will~ignore~this~entire~definition.
+  }
 \__kernel_msg_new:nnnn { xparse } { non-xparse-command }
   { Command~'#1'~not~defined~using~xparse. }
   {
@@ -4219,6 +4272,12 @@
     This~cannot~be~implemented. \\ \\
     LaTeX~will~ignore~this~entire~definition.
   }
+\__kernel_msg_new:nnnn { xparse } { two-markers }
+  { Two~'#2'~apply~to~the~same~argument~in~argument~specification~of~command~'#1'. }
+  {
+    The~argument~specification~provided~has~two~markers~'#2'~applying~
+    to~the~same~argument;~these~are~redundant.
+  }
 \__kernel_msg_new:nnnn { xparse } { unknown-argument-type }
   { Unknown~argument~type~'#2'~for~the~command~'#1'. }
   {
diff --git a/Master/texmf-dist/source/latex/l3packages/xtemplate/xtemplate.dtx b/Master/texmf-dist/source/latex/l3packages/xtemplate/xtemplate.dtx
index 182e8be40f8..d0f69f40172 100644
--- a/Master/texmf-dist/source/latex/l3packages/xtemplate/xtemplate.dtx
+++ b/Master/texmf-dist/source/latex/l3packages/xtemplate/xtemplate.dtx
@@ -63,7 +63,7 @@
 %    }^^A
 % }
 %
-% \date{Released 2018-08-23}
+% \date{Released 2018-09-24}
 %
 % \maketitle
 %
@@ -682,7 +682,7 @@
 %    \end{macrocode}
 %
 %    \begin{macrocode}
-\ProvidesExplPackage{xtemplate}{2018-08-23}{}
+\ProvidesExplPackage{xtemplate}{2018-09-24}{}
   {L3 Experimental prototype document functions}
 %    \end{macrocode}
 %