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|
% \iffalse meta-comment
%
%% File: l3prop.dtx Copyright (C) 1990-2013 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 "l3kernel 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{l3bootstrap}
\GetIdInfo$Id: l3prop.dtx 4581 2013-07-28 08:38:50Z joseph $
{L3 Property lists}
%</driver|package>
%<*driver>
\documentclass[full]{l3doc}
\begin{document}
\DocInput{\jobname.dtx}
\end{document}
%</driver>
% \fi
%
% \title{^^A
% The \pkg{l3prop} package\\ Property lists^^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}
%
% \LaTeX3 implements a \enquote{property list} data type, which contain
% an unordered list of entries each of which consists of a \meta{key} and
% an associated \meta{value}. The \meta{key} and \meta{value} may both be
% any \meta{balanced text}. It is possible to map functions to property lists
% such that the function is applied to every key--value pair within
% the list.
%
% Each entry in a property list must have a unique \meta{key}: if an entry is
% added to a property list which already contains the \meta{key} then the new
% entry will overwrite the existing one. The \meta{keys} are compared on a
% string basis, using the same method as \cs{str_if_eq:nn}.
%
% Property lists are intended for storing key-based information for use within
% code. This is in contrast to key--value lists, which are a form of
% \emph{input} parsed by the \pkg{keys} module.
%
% \section{Creating and initialising property lists}
%
% \begin{function}{\prop_new:N, \prop_new:c}
% \begin{syntax}
% \cs{prop_new:N} \meta{property list}
% \end{syntax}
% Creates a new \meta{property list} or raises an error if the name is
% already taken. The declaration is global. The \meta{property list} will
% initially contain no entries.
% \end{function}
%
% \begin{function}
% {\prop_clear:N, \prop_clear:c, \prop_gclear:N, \prop_gclear:c}
% \begin{syntax}
% \cs{prop_clear:N} \meta{property list}
% \end{syntax}
% Clears all entries from the \meta{property list}.
% \end{function}
%
% \begin{function}
% {
% \prop_clear_new:N, \prop_clear_new:c,
% \prop_gclear_new:N, \prop_gclear_new:c
% }
% \begin{syntax}
% \cs{prop_clear_new:N} \meta{property list}
% \end{syntax}
% Ensures that the \meta{property list} exists globally by applying
% \cs{prop_new:N} if necessary, then applies \cs{prop_(g)clear:N} to leave
% the list empty.
% \end{function}
%
% \begin{function}
% {
% \prop_set_eq:NN, \prop_set_eq:cN, \prop_set_eq:Nc, \prop_set_eq:cc,
% \prop_gset_eq:NN, \prop_gset_eq:cN, \prop_gset_eq:Nc, \prop_gset_eq:cc
% }
% \begin{syntax}
% \cs{prop_set_eq:NN} \meta{property list_1} \meta{property list_2}
% \end{syntax}
% Sets the content of \meta{property list_1} equal to that of
% \meta{property list_2}.
% \end{function}
%
% \section{Adding entries to property lists}
%
% \begin{function}[updated = 2012-07-09]
% {
% \prop_put:Nnn, \prop_put:NnV, \prop_put:Nno, \prop_put:Nnx,
% \prop_put:NVn, \prop_put:NVV, \prop_put:Non, \prop_put:Noo,
% \prop_put:cnn, \prop_put:cnV, \prop_put:cno, \prop_put:cnx,
% \prop_put:cVn, \prop_put:cVV, \prop_put:con, \prop_put:coo,
% \prop_gput:Nnn, \prop_gput:NnV, \prop_gput:Nno, \prop_gput:Nnx,
% \prop_gput:NVn, \prop_gput:NVV, \prop_gput:Non, \prop_gput:Noo,
% \prop_gput:cnn, \prop_gput:cnV, \prop_gput:cno, \prop_gput:cnx,
% \prop_gput:cVn, \prop_gput:cVV, \prop_gput:con, \prop_gput:coo
% }
% \begin{syntax}
% \cs{prop_put:Nnn} \meta{property list} \Arg{key} \Arg{value}
% \end{syntax}
% Adds an entry to the \meta{property list} which may be accessed
% using the \meta{key} and which has \meta{value}. Both the \meta{key}
% and \meta{value} may contain any \meta{balanced text}. The \meta{key}
% is stored after processing with \cs{tl_to_str:n}, meaning that
% category codes are ignored. If the \meta{key} is already present
% in the \meta{property list}, the existing entry is overwritten
% by the new \meta{value}.
% \end{function}
%
% \begin{function}
% {
% \prop_put_if_new:Nnn, \prop_put_if_new:cnn,
% \prop_gput_if_new:Nnn, \prop_gput_if_new:cnn
% }
% \begin{syntax}
% \cs{prop_put_if_new:Nnn} \meta{property list} \Arg{key} \Arg{value}
% \end{syntax}
% If the \meta{key} is present in the \meta{property list} then
% no action is taken. If the \meta{key} is not present in the
% \meta{property list} then a new entry is added. Both the \meta{key}
% and \meta{value} may contain any \meta{balanced text}. The \meta{key}
% is stored after processing with \cs{tl_to_str:n}, meaning that
% category codes are ignored.
% \end{function}
%
% \section{Recovering values from property lists}
%
% \begin{function}[updated = 2011-08-28]
% {
% \prop_get:NnN, \prop_get:NVN, \prop_get:NoN,
% \prop_get:cnN, \prop_get:cVN, \prop_get:coN,
% }
% \begin{syntax}
% \cs{prop_get:NnN} \meta{property list} \Arg{key} \meta{tl var}
% \end{syntax}
% Recovers the \meta{value} stored with \meta{key} from the
% \meta{property list}, and places this in the \meta{token list
% variable}. If the \meta{key} is not found in the
% \meta{property list} then the \meta{token list variable} will
% contain the special marker \cs{q_no_value}. The \meta{token list
% variable} is set within the current \TeX{} group. See also
% \cs{prop_get:NnNTF}.
% \end{function}
%
% \begin{function}[updated = 2011-08-18]
% {\prop_pop:NnN, \prop_pop:NoN, \prop_pop:cnN, \prop_pop:coN}
% \begin{syntax}
% \cs{prop_pop:NnN} \meta{property list} \Arg{key} \meta{tl var}
% \end{syntax}
% Recovers the \meta{value} stored with \meta{key} from the
% \meta{property list}, and places this in the \meta{token list
% variable}. If the \meta{key} is not found in the
% \meta{property list} then the \meta{token list variable} will
% contain the special marker \cs{q_no_value}. The \meta{key} and
% \meta{value} are then deleted from the property list. Both
% assignments are local. See also \cs{prop_pop:NnNTF}.
% \end{function}
%
% \begin{function}[updated = 2011-08-18]
% {\prop_gpop:NnN, \prop_gpop:NoN, \prop_gpop:cnN, \prop_gpop:coN}
% \begin{syntax}
% \cs{prop_gpop:NnN} \meta{property list} \Arg{key} \meta{tl var}
% \end{syntax}
% Recovers the \meta{value} stored with \meta{key} from the
% \meta{property list}, and places this in the \meta{token list
% variable}. If the \meta{key} is not found in the
% \meta{property list} then the \meta{token list variable} will
% contain the special marker \cs{q_no_value}. The \meta{key} and
% \meta{value} are then deleted from the property list.
% The \meta{property list} is modified globally, while the assignment of
% the \meta{token list variable} is local. See also \cs{prop_gpop:NnNTF}.
% \end{function}
%
% \section{Modifying property lists}
%
% \begin{function}[added = 2012-05-12]
% {
% \prop_remove:Nn, \prop_remove:NV, \prop_remove:cn, \prop_remove:cV,
% \prop_gremove:Nn, \prop_gremove:NV, \prop_gremove:cn, \prop_gremove:cV
% }
% \begin{syntax}
% \cs{prop_remove:Nn} \meta{property list} \Arg{key}
% \end{syntax}
% Removes the entry listed under \meta{key} from the
% \meta{property list}. If the \meta{key} is
% not found in the \meta{property list} no change occurs,
% \emph{i.e}~there is no need to test for the existence of a key before
% deleting it.
% \end{function}
%
% \section{Property list conditionals}
%
% \begin{function}[EXP, pTF, added = 2012-03-03]
% {\prop_if_exist:N, \prop_if_exist:c}
% \begin{syntax}
% \cs{prop_if_exist_p:N} \meta{property list}
% \cs{prop_if_exist:NTF} \meta{property list} \Arg{true code} \Arg{false code}
% \end{syntax}
% Tests whether the \meta{property list} is currently defined. This does not
% check that the \meta{property list} really is a property list variable.
% \end{function}
%
% \begin{function}[EXP, pTF]{\prop_if_empty:N, \prop_if_empty:c}
% \begin{syntax}
% \cs{prop_if_empty_p:N} \meta{property list}
% \cs{prop_if_empty:NTF} \meta{property list} \Arg{true code} \Arg{false code}
% \end{syntax}
% Tests if the \meta{property list} is empty (containing no entries).
% \end{function}
%
% \begin{function}[updated = 2011-09-15, EXP, pTF]
% {
% \prop_if_in:Nn, \prop_if_in:NV, \prop_if_in:No,
% \prop_if_in:cn, \prop_if_in:cV, \prop_if_in:co
% }
% \begin{syntax}
% \cs{prop_if_in:NnTF} \meta{property list} \Arg{key} \Arg{true code} \Arg{false code}
% \end{syntax}
% Tests if the \meta{key} is present in the \meta{property list},
% making the comparison using the method described by \cs{str_if_eq:nnTF}.
% \begin{texnote}
% This function iterates through every key--value pair in the
% \meta{property list} and is therefore slower than using the
% non-expandable \cs{prop_get:NnNTF}.
% \end{texnote}
% \end{function}
%
% \section{Recovering values from property lists with branching}
%
% The functions in this section combine tests for the presence of a key
% in a property list with recovery of the associated valued. This makes them
% useful for cases where different cases follow dependent on the presence
% or absence of a key in a property list. They offer increased readability
% and performance over separate testing and recovery phases.
%
% \begin{function}[updated = 2012-05-19, TF]
% {
% \prop_get:NnN, \prop_get:NVN, \prop_get:NoN,
% \prop_get:cnN, \prop_get:cVN, \prop_get:coN
% }
% \begin{syntax}
% \cs{prop_get:NnNTF} \meta{property list} \Arg{key} \meta{token list variable} \\
% ~~\Arg{true code} \Arg{false code}
% \end{syntax}
% If the \meta{key} is not present in the \meta{property list}, leaves
% the \meta{false code} in the input stream. The value of the
% \meta{token list variable} is not defined in this case and should
% not be relied upon. If the \meta{key} is present in the
% \meta{property list}, stores the corresponding \meta{value} in the
% \meta{token list variable} without removing it from the
% \meta{property list}, then leaves the \meta{true code} in the input
% stream. The \meta{token list variable} is assigned locally.
% \end{function}
%
% \begin{function}[TF, added = 2011-08-18, updated = 2012-05-19]
% {\prop_pop:NnN, \prop_pop:cnN}
% \begin{syntax}
% \cs{prop_pop:NnNTF} \meta{property list} \Arg{key} \meta{token list variable} \Arg{true code} \Arg{false code}
% \end{syntax}
% If the \meta{key} is not present in the \meta{property list}, leaves
% the \meta{false code} in the input stream. The value of the
% \meta{token list variable} is not defined in this case and should
% not be relied upon. If the \meta{key} is present in
% the \meta{property list}, pops the corresponding \meta{value}
% in the \meta{token list variable}, \emph{i.e.}~removes the item from
% the \meta{property list}.
% Both the \meta{property list} and the \meta{token list variable}
% are assigned locally.
% \end{function}
%
% \begin{function}[TF, added = 2011-08-18, updated = 2012-05-19]
% {\prop_gpop:NnN, \prop_gpop:cnN}
% \begin{syntax}
% \cs{prop_gpop:NnNTF} \meta{property list} \Arg{key} \meta{token list variable} \Arg{true code} \Arg{false code}
% \end{syntax}
% If the \meta{key} is not present in the \meta{property list}, leaves
% the \meta{false code} in the input stream. The value of the
% \meta{token list variable} is not defined in this case and should
% not be relied upon. If the \meta{key} is present in
% the \meta{property list}, pops the corresponding \meta{value}
% in the \meta{token list variable}, \emph{i.e.}~removes the item from
% the \meta{property list}.
% The \meta{property list} is modified globally, while the
% \meta{token list variable} is assigned locally.
% \end{function}
%
% \section{Mapping to property lists}
%
% \begin{function}[updated = 2013-01-08, rEXP]
% {\prop_map_function:NN, \prop_map_function:cN}
% \begin{syntax}
% \cs{prop_map_function:NN} \meta{property list} \meta{function}
% \end{syntax}
% Applies \meta{function} to every \meta{entry} stored in the
% \meta{property list}. The \meta{function} will receive two argument for
% each iteration: the \meta{key} and associated \meta{value}.
% The order in which \meta{entries} are returned is not defined and
% should not be relied upon.
% \end{function}
%
% \begin{function}[updated = 2013-01-08]
% {\prop_map_inline:Nn, \prop_map_inline:cn}
% \begin{syntax}
% \cs{prop_map_inline:Nn} \meta{property list} \Arg{inline function}
% \end{syntax}
% Applies \meta{inline function} to every \meta{entry} stored
% within the \meta{property list}. The \meta{inline function} should
% consist of code which will receive the \meta{key} as |#1| and the
% \meta{value} as |#2|.
% The order in which \meta{entries} are returned is not defined and
% should not be relied upon.
% \end{function}
%
% \begin{function}[updated = 2012-06-29, rEXP]{\prop_map_break:}
% \begin{syntax}
% \cs{prop_map_break:}
% \end{syntax}
% Used to terminate a \cs{prop_map_\ldots} function before all
% entries in the \meta{property list} have been processed. This will
% normally take place within a conditional statement, for example
% \begin{verbatim}
% \prop_map_inline:Nn \l_my_prop
% {
% \str_if_eq:nnTF { #1 } { bingo }
% { \prop_map_break: }
% {
% % Do something useful
% }
% }
% \end{verbatim}
% Use outside of a \cs{prop_map_\ldots} scenario will lead to low
% level \TeX{} errors.
% \end{function}
%
% \begin{function}[updated = 2012-06-29, rEXP]{\prop_map_break:n}
% \begin{syntax}
% \cs{prop_map_break:n} \Arg{tokens}
% \end{syntax}
% Used to terminate a \cs{prop_map_\ldots} function before all
% entries in the \meta{property list} have been processed, inserting
% the \meta{tokens} after the mapping has ended. This will
% normally take place within a conditional statement, for example
% \begin{verbatim}
% \prop_map_inline:Nn \l_my_prop
% {
% \str_if_eq:nnTF { #1 } { bingo }
% { \prop_map_break:n { <tokens> } }
% {
% % Do something useful
% }
% }
% \end{verbatim}
% Use outside of a \cs{prop_map_\ldots} scenario will lead to low
% level \TeX{} errors.
% \end{function}
%
% \section{Viewing property lists}
%
% \begin{function}[updated = 2012-09-09]{\prop_show:N, \prop_show:c}
% \begin{syntax}
% \cs{prop_show:N} \meta{property list}
% \end{syntax}
% Displays the entries in the \meta{property list} in the terminal.
% \end{function}
%
% \section{Scratch property lists}
%
% \begin{variable}[added = 2012-06-23]{\l_tmpa_prop, \l_tmpb_prop}
% Scratch property lists 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}
%
% \begin{variable}[added = 2012-06-23]{\g_tmpa_prop, \g_tmpb_prop}
% Scratch property lists for global 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{Constants}
%
% \begin{variable}{\c_empty_prop}
% A permanently-empty property list used for internal comparisons.
% \end{variable}
%
% \section{Internal property list functions}
%
% \begin{variable}{\s__prop}
% The internal token used at the beginning of property lists. This is
% also used after each \meta{key} (see \cs{__prop_pair:wn}).
% \end{variable}
%
% \begin{variable}{\__prop_pair:wn}
% \begin{syntax}
% \cs{__prop_pair:wn} \meta{key} \cs{s__prop} \Arg{item}
% \end{syntax}
% The internal token used to begin each key--value pair in the
% property list. If expanded outside of a mapping or manipulation
% function, an error will be raised. The definition should always be
% set globally.
% \end{variable}
%
% \begin{variable}{\l__prop_internal_tl}
% Token list used to store new key--value pairs to be inserted by
% functions of the \cs{prop_put:Nnn} family.
% \end{variable}
%
% \begin{function}[updated = 2013-01-08]{\__prop_split:NnTF}
% \begin{syntax}
% \cs{__prop_split:NnTF} \meta{property list} \Arg{key} \Arg{true code} \Arg{false code}
% \end{syntax}
% Splits the \meta{property list} at the \meta{key}, giving three
% token lists: the \meta{extract} of \meta{property list} before the
% \meta{key}, the \meta{value} associated with the \meta{key} and the
% \meta{extract} of the \meta{property list} after the \meta{value}.
% Both \meta{extracts} retain the internal structure of a property
% list, and the concatenation of the two \meta{extracts} is a
% property list.
% If the \meta{key} is present in the \meta{property list} then the
% \meta{true code} is left in the input stream, with |#1|, |#2|, and
% |#3| replaced by the first \meta{extract}, the \meta{value}, and the
% second extract.
% If the \meta{key} is not present in the \meta{property list} then
% the \meta{false code} is left in the input stream, with no trailing
% material.
% Both \meta{true code} and \meta{false code} are used in the
% replacement text of a macro defined internally, hence macro
% parameter characters should be doubled, except |#1|, |#2|, and |#3|
% which stand in the \meta{true code} for the three extracts from the
% property list.
% The \meta{key} comparison takes place as described for \cs{str_if_eq:nn}.
% \end{function}
%
% \end{documentation}
%
% \begin{implementation}
%
% \section{\pkg{l3prop} implementation}
%
% \TestFiles{m3prop001, m3prop002, m3prop003, m3prop004, m3show001}
%
% \begin{macrocode}
%<*initex|package>
% \end{macrocode}
%
% \begin{macrocode}
%<@@=prop>
% \end{macrocode}
%
% \begin{macrocode}
%<*package>
\ProvidesExplPackage
{\ExplFileName}{\ExplFileDate}{\ExplFileVersion}{\ExplFileDescription}
\__expl_package_check:
%</package>
% \end{macrocode}
%
% A property list is a macro whose top-level expansion is for the form
% \begin{quote}
% \cs{s_@@}
% \cs{@@_pair:wn} \meta{key_1} \cs{s_@@} \Arg{value_1} \\
% \ldots{} \\
% \cs{@@_pair:wn} \meta{key_n} \cs{s_@@} \Arg{value_n} \\
% \cs{s_obj_end}
% \end{quote}
% where the separators \cs{s_@@} and \cs{s_obj_end} are scan marks
% (equal to \cs{scan_stop:}), and \cs{@@_pair:wn} can be used to map
% through the property list.
%
% \begin{macro}[int]{\s_@@}
% A private scan mark is used as a marker after each key, and at the
% very beginning of the property list.
% \begin{macrocode}
\__scan_new:N \s_@@
% \end{macrocode}
% \end{macro}
%
% \begin{macro}[int]{\@@_pair:wn}
% The delimiter is always defined, but when misused simply triggers an
% error and removes its argument.
% \begin{macrocode}
\cs_new:Npn \@@_pair:wn #1 \s_@@ #2
{ \__msg_kernel_expandable_error:nn { kernel } { misused-prop } }
% \end{macrocode}
% \end{macro}
%
% \begin{variable}{\l_@@_internal_tl}
% Token list used to store the new key--value pair inserted by
% \cs{prop_put:Nnn} and friends.
% \begin{macrocode}
\tl_new:N \l_@@_internal_tl
% \end{macrocode}
% \end{variable}
%
% \begin{variable}[tested = m3prop004]{\c_empty_prop}
% An empty prop.
% \begin{macrocode}
\tl_const:Nn \c_empty_prop { \s_@@ \s_obj_end }
% \end{macrocode}
% \end{variable}
%
% \subsection{Allocation and initialisation}
%
% \begin{macro}[tested = m3prop001]{\prop_new:N, \prop_new:c}
% Property lists are initialized with the value \cs{c_empty_prop}.
% \begin{macrocode}
\cs_new_protected:Npn \prop_new:N #1
{
\__chk_if_free_cs:N #1
\cs_gset_eq:NN #1 \c_empty_prop
}
\cs_generate_variant:Nn \prop_new:N { c }
% \end{macrocode}
% \end{macro}
%
% \begin{macro}[tested = m3prop001]{\prop_clear:N, \prop_clear:c}
% \begin{macro}[tested = m3prop001]{\prop_gclear:N, \prop_gclear:c}
% The same idea for clearing.
% \begin{macrocode}
\cs_new_protected:Npn \prop_clear:N #1
{ \prop_set_eq:NN #1 \c_empty_prop }
\cs_generate_variant:Nn \prop_clear:N { c }
\cs_new_protected:Npn \prop_gclear:N #1
{ \prop_gset_eq:NN #1 \c_empty_prop }
\cs_generate_variant:Nn \prop_gclear:N { c }
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}[tested = m3prop001]{\prop_clear_new:N, \prop_clear_new:c}
% \begin{macro}[tested = m3prop001]{\prop_gclear_new:N, \prop_gclear_new:c}
% Once again a simple variation of the token list functions.
% \begin{macrocode}
\cs_new_protected:Npn \prop_clear_new:N #1
{ \prop_if_exist:NTF #1 { \prop_clear:N #1 } { \prop_new:N #1 } }
\cs_generate_variant:Nn \prop_clear_new:N { c }
\cs_new_protected:Npn \prop_gclear_new:N #1
{ \prop_if_exist:NTF #1 { \prop_gclear:N #1 } { \prop_new:N #1 } }
\cs_generate_variant:Nn \prop_gclear_new:N { c }
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}[tested = m3prop001]
% {\prop_set_eq:NN, \prop_set_eq:cN, \prop_set_eq:Nc, \prop_set_eq:cc}
% \begin{macro}[tested = m3prop001]
% {\prop_gset_eq:NN, \prop_gset_eq:cN, \prop_gset_eq:Nc, \prop_gset_eq:cc}
% These are simply copies from the token list functions.
% \begin{macrocode}
\cs_new_eq:NN \prop_set_eq:NN \tl_set_eq:NN
\cs_new_eq:NN \prop_set_eq:Nc \tl_set_eq:Nc
\cs_new_eq:NN \prop_set_eq:cN \tl_set_eq:cN
\cs_new_eq:NN \prop_set_eq:cc \tl_set_eq:cc
\cs_new_eq:NN \prop_gset_eq:NN \tl_gset_eq:NN
\cs_new_eq:NN \prop_gset_eq:Nc \tl_gset_eq:Nc
\cs_new_eq:NN \prop_gset_eq:cN \tl_gset_eq:cN
\cs_new_eq:NN \prop_gset_eq:cc \tl_gset_eq:cc
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{variable}[tested = m3prop004]{\l_tmpa_prop, \l_tmpb_prop}
% \begin{variable}[tested = m3prop004]{\g_tmpa_prop, \g_tmpb_prop}
% We can now initialize the scratch variables.
% \begin{macrocode}
\prop_new:N \l_tmpa_prop
\prop_new:N \l_tmpb_prop
\prop_new:N \g_tmpa_prop
\prop_new:N \g_tmpb_prop
% \end{macrocode}
% \end{variable}
% \end{variable}
%
% \subsection{Accessing data in property lists}
%
% \begin{macro}[EXP]{\@@_strip_end:w}
% Strip the \cs{s_obj_end} marker from an expanded property list
% variable.
% \begin{macrocode}
\cs_new:Npn \@@_strip_end:w #1 \s_obj_end { \exp_not:n {#1} }
% \end{macrocode}
% \end{macro}
%
% \begin{macro}[int]{\@@_split:NnTF}
% \begin{macro}[aux]{\@@_split_aux:NnTF}
% \begin{macro}[aux, EXP]{\@@_split_aux:w}
% This function is used by most of the module, and hence must be fast.
% It receives a \meta{property list}, a \meta{key}, a \meta{true code}
% and a \meta{false code}. The aim is to split the \meta{property
% list} at the given \meta{key} into the \meta{extract_1} before the
% key--value pair, the \meta{value} associated with the \meta{key} and
% the \meta{extract_2} after the key--value pair. This is done using
% a delimited function, whose definition is as follows, where the
% \meta{key} is turned into a string.
% \begin{quote}
% \cs{cs_set:Npn} \cs{@@_split_aux:w} |#1| \\
% \quad \cs{@@_pair:wn} \meta{key} \cs{s_@@} |#2| \\
% \quad |#3| \cs{q_mark} |#4| |#5| \cs{q_stop} \\
% \quad |{| |#4| \Arg{true code} \Arg{false code} |}|
% \end{quote}
%
% If the \meta{key} is present in the property list,
% \cs{@@_split_aux:w}'s |#1| is the part before the \meta{key}, |#2|
% is the \meta{value}, |#3| is the part after the \meta{key}, |#4| is
% \cs{use_i:nn}, and |#5| is additional tokens that we do not care
% about. The \meta{true code} is left in the input stream, and can
% use the parameters |#1|, |#2|, |#3| for the three parts of the
% property list as desired. Namely, the original property list is in
% this case |#1| \cs{@@_pair:wn} \meta{key} \cs{s_@@} |{#2}| |#3|.
%
% If the \meta{key} is not there, then the \meta{function} is
% \cs{use_ii:nn}, which keeps the \meta{false code}.
% \begin{macrocode}
\cs_new_protected:Npn \@@_split:NnTF #1#2
{ \exp_args:NNo \@@_split_aux:NnTF #1 { \tl_to_str:n {#2} } }
\cs_new_protected:Npn \@@_split_aux:NnTF #1#2#3#4
{
\cs_set:Npn \@@_split_aux:w ##1
\@@_pair:wn #2 \s_@@ ##2 ##3 \q_mark ##4 ##5 \q_stop
{ ##4 {#3} {#4} }
\exp_after:wN \@@_split_aux:w #1 \q_mark \use_i:nn
\@@_pair:wn #2 \s_@@ { } \q_mark \use_ii:nn \q_stop
}
\cs_new:Npn \@@_split_aux:w { }
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
%
% \begin{macro}[tested = m3prop002]
% {\prop_remove:Nn, \prop_remove:NV, \prop_remove:cn, \prop_remove:cV}
% \begin{macro}[tested = m3prop002]
% {\prop_gremove:Nn, \prop_gremove:NV, \prop_gremove:cn, \prop_gremove:cV}
% Deleting from a property starts by splitting the list.
% If the key is present in the property list, the returned value is ignored.
% If the key is missing, nothing happens.
% \begin{macrocode}
\cs_new_protected:Npn \prop_remove:Nn #1#2
{
\@@_split:NnTF #1 {#2}
{ \tl_set:Nn #1 { ##1 ##3 } }
{ }
}
\cs_new_protected:Npn \prop_gremove:Nn #1#2
{
\@@_split:NnTF #1 {#2}
{ \tl_gset:Nn #1 { ##1 ##3 } }
{ }
}
\cs_generate_variant:Nn \prop_remove:Nn { NV }
\cs_generate_variant:Nn \prop_remove:Nn { c , cV }
\cs_generate_variant:Nn \prop_gremove:Nn { NV }
\cs_generate_variant:Nn \prop_gremove:Nn { c , cV }
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}[tested = m3prop002]
% {
% \prop_get:NnN, \prop_get:NVN, \prop_get:NoN,
% \prop_get:cnN, \prop_get:cVN, \prop_get:coN
% }
% Getting an item from a list is very easy: after splitting,
% if the key is in the property list, just set the token list variable
% to the return value, otherwise to \cs{q_no_value}.
% \begin{macrocode}
\cs_new_protected:Npn \prop_get:NnN #1#2#3
{
\@@_split:NnTF #1 {#2}
{ \tl_set:Nn #3 {##2} }
{ \tl_set:Nn #3 { \q_no_value } }
}
\cs_generate_variant:Nn \prop_get:NnN { NV , No }
\cs_generate_variant:Nn \prop_get:NnN { c , cV , co }
% \end{macrocode}
% \end{macro}
%
% \begin{macro}[tested = m3prop002]
% {\prop_pop:NnN, \prop_pop:NoN, \prop_pop:cnN, \prop_pop:coN}
% \begin{macro}[tested = m3prop002]
% {\prop_gpop:NnN, \prop_gpop:NoN, \prop_gpop:cnN, \prop_gpop:coN}
% Popping a value also starts by doing the split.
% If the key is present, save the value in the token list and update the
% property list as when deleting.
% If the key is missing, save \cs{q_no_value} in the token list.
% \begin{macrocode}
\cs_new_protected:Npn \prop_pop:NnN #1#2#3
{
\@@_split:NnTF #1 {#2}
{
\tl_set:Nn #3 {##2}
\tl_set:Nn #1 { ##1 ##3 }
}
{ \tl_set:Nn #3 { \q_no_value } }
}
\cs_new_protected:Npn \prop_gpop:NnN #1#2#3
{
\@@_split:NnTF #1 {#2}
{
\tl_set:Nn #3 {##2}
\tl_gset:Nn #1 { ##1 ##3 }
}
{ \tl_set:Nn #3 { \q_no_value } }
}
\cs_generate_variant:Nn \prop_pop:NnN { No }
\cs_generate_variant:Nn \prop_pop:NnN { c , co }
\cs_generate_variant:Nn \prop_gpop:NnN { No }
\cs_generate_variant:Nn \prop_gpop:NnN { c , co }
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}[TF, tested = m3prop004]
% {\prop_pop:NnN, \prop_pop:cnN, \prop_gpop:NnN, \prop_gpop:cnN}
% Popping an item from a property list, keeping track of whether
% the key was present or not, is implemented as a conditional.
% If the key was missing, neither the property list, nor the token
% list are altered. Otherwise, \cs{prg_return_true:} is used after
% the assignments.
% \begin{macrocode}
\prg_new_protected_conditional:Npnn \prop_pop:NnN #1#2#3 { T , F , TF }
{
\@@_split:NnTF #1 {#2}
{
\tl_set:Nn #3 {##2}
\tl_set:Nn #1 { ##1 ##3 }
\prg_return_true:
}
{ \prg_return_false: }
}
\prg_new_protected_conditional:Npnn \prop_gpop:NnN #1#2#3 { T , F , TF }
{
\@@_split:NnTF #1 {#2}
{
\tl_set:Nn #3 {##2}
\tl_gset:Nn #1 { ##1 ##3 }
\prg_return_true:
}
{ \prg_return_false: }
}
\cs_generate_variant:Nn \prop_pop:NnNT { c }
\cs_generate_variant:Nn \prop_pop:NnNF { c }
\cs_generate_variant:Nn \prop_pop:NnNTF { c }
\cs_generate_variant:Nn \prop_gpop:NnNT { c }
\cs_generate_variant:Nn \prop_gpop:NnNF { c }
\cs_generate_variant:Nn \prop_gpop:NnNTF { c }
% \end{macrocode}
% \end{macro}
%
% \begin{macro}[tested = m3prop002]
% {
% \prop_put:Nnn, \prop_put:NnV, \prop_put:Nno, \prop_put:Nnx,
% \prop_put:NVn, \prop_put:NVV, \prop_put:Non, \prop_put:Noo,
% \prop_put:cnn, \prop_put:cnV, \prop_put:cno, \prop_put:cnx,
% \prop_put:cVn, \prop_put:cVV, \prop_put:con, \prop_put:coo
% }
% \begin{macro}[tested = m3prop002]
% {
% \prop_gput:Nnn, \prop_gput:NnV, \prop_gput:Nno, \prop_gput:Nnx,
% \prop_gput:NVn, \prop_gput:NVV, \prop_gput:Non, \prop_gput:Noo,
% \prop_gput:cnn, \prop_gput:cnV, \prop_gput:cno, \prop_gput:cnx,
% \prop_gput:cVn, \prop_gput:cVV, \prop_gput:con, \prop_gput:coo
% }
% \begin{macro}[aux]{\@@_put:NNnn}
% Since the branches of \cs{@@_split:NnTF} are used as the replacement
% text of an internal macro, and since the \meta{key} and new
% \meta{value} may contain arbitrary tokens, it is not safe to include
% them in the argument of \cs{@@_split:NnTF}. We thus start by
% storing in \cs{l_@@_internal_tl} tokens which (after
% \texttt{x}-expansion) encode the key--value pair. This variable can
% safely be used in \cs{@@_split:NnTF}. If the \meta{key} was absent,
% append the new key--value to the list (\cs{@@_strip_end:w} moves the
% \cs{s_obj_end} marker). Otherwise concatenate the extracts |##1|
% and |##3| with the new key--value pair \cs{l_@@_internal_tl}. The
% updated entry is placed at the same spot as the original \meta{key}
% in the property list, preserving the order of entries.
% \begin{macrocode}
\cs_new_protected_nopar:Npn \prop_put:Nnn { \@@_put:NNnn \tl_set:Nx }
\cs_new_protected_nopar:Npn \prop_gput:Nnn { \@@_put:NNnn \tl_gset:Nx }
\cs_new_protected:Npn \@@_put:NNnn #1#2#3#4
{
\tl_set:Nn \l_@@_internal_tl
{
\exp_not:N \@@_pair:wn \tl_to_str:n {#3}
\s_@@ { \exp_not:n {#4} }
}
\@@_split:NnTF #2 {#3}
{ #1 #2 { \exp_not:n {##1} \l_@@_internal_tl \exp_not:n {##3} } }
{
#1 #2
{
\exp_after:wN \@@_strip_end:w #2
\l_@@_internal_tl \s_obj_end
}
}
}
\cs_generate_variant:Nn \prop_put:Nnn
{ NnV , Nno , Nnx , NV , NVV , No , Noo }
\cs_generate_variant:Nn \prop_put:Nnn
{ c , cnV , cno , cnx , cV , cVV , co , coo }
\cs_generate_variant:Nn \prop_gput:Nnn
{ NnV , Nno , Nnx , NV , NVV , No , Noo }
\cs_generate_variant:Nn \prop_gput:Nnn
{ c , cnV , cno , cnx , cV , cVV , co , coo }
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
%
% \begin{macro}[tested = m3prop002]
% {\prop_put_if_new:Nnn, \prop_put_if_new:cnn}
% \begin{macro}[tested = m3prop002]
% {\prop_gput_if_new:Nnn, \prop_gput_if_new:cnn}
% \begin{macro}[aux]{\@@_put_if_new:NNnn}
% Adding conditionally also splits. If the key is already present,
% the three brace groups given by \cs{@@_split:NnTF} are removed.
% If the key is new, then the value is added, being careful to
% convert the key to a string using \cs{tl_to_str:n}.
% \begin{macrocode}
\cs_new_protected_nopar:Npn \prop_put_if_new:Nnn
{ \@@_put_if_new:NNnn \tl_set:Nx }
\cs_new_protected_nopar:Npn \prop_gput_if_new:Nnn
{ \@@_put_if_new:NNnn \tl_gset:Nx }
\cs_new_protected:Npn \@@_put_if_new:NNnn #1#2#3#4
{
\tl_set:Nn \l_@@_internal_tl
{
\exp_not:N \@@_pair:wn \tl_to_str:n {#3}
\s_@@ \exp_not:n { {#4} }
}
\@@_split:NnTF #2 {#3}
{ }
{
#1 #2
{
\exp_after:wN \@@_strip_end:w #2
\l_@@_internal_tl \s_obj_end
}
}
}
\cs_generate_variant:Nn \prop_put_if_new:Nnn { c }
\cs_generate_variant:Nn \prop_gput_if_new:Nnn { c }
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
%
% \subsection{Property list conditionals}
%
% \begin{macro}[pTF, tested = m3prop004]{\prop_if_exist:N, \prop_if_exist:c}
% Copies of the \texttt{cs} functions defined in \pkg{l3basics}.
% \begin{macrocode}
\prg_new_eq_conditional:NNn \prop_if_exist:N \cs_if_exist:N { TF , T , F , p }
\prg_new_eq_conditional:NNn \prop_if_exist:c \cs_if_exist:c { TF , T , F , p }
% \end{macrocode}
% \end{macro}
%
% \begin{macro}[pTF, tested = m3prop003]{\prop_if_empty:N, \prop_if_empty:c}
% Same test as for token lists.
% \begin{macrocode}
\prg_new_conditional:Npnn \prop_if_empty:N #1 { p , T , F , TF }
{
\tl_if_eq:NNTF #1 \c_empty_prop
\prg_return_true: \prg_return_false:
}
\cs_generate_variant:Nn \prop_if_empty_p:N { c }
\cs_generate_variant:Nn \prop_if_empty:NT { c }
\cs_generate_variant:Nn \prop_if_empty:NF { c }
\cs_generate_variant:Nn \prop_if_empty:NTF { c }
% \end{macrocode}
% \end{macro}
%
% \begin{macro}[pTF, tested = m3prop003]
% {
% \prop_if_in:Nn, \prop_if_in:NV, \prop_if_in:No,
% \prop_if_in:cn, \prop_if_in:cV, \prop_if_in:co
% }
% \begin{macro}[aux,EXP]{\@@_if_in:nwwn,\@@_if_in:N}
% Testing expandably if a key is in a property list
% requires to go through the key--value pairs one by one.
% This is rather slow, and a faster test would be
% \begin{verbatim}
% \prg_new_protected_conditional:Npnn \prop_if_in:Nn #1 #2
% {
% \@@_split:NnTF #1 {#2}
% { \prg_return_true: }
% { \prg_return_false: }
% }
% \end{verbatim}
% but \cs{@@_split:NnTF} is non-expandable.
%
% Instead, the key is compared to each key in turn using
% \cs{str_if_eq_x:nn}, which is expandable. To terminate the mapping,
% we append to the property list the key that is searched for. This
% second \cs{tl_to_str:n} is not expanded at the start, but only when
% included in the \cs{str_if_eq_x:nn}. It cannot make the breaking
% mechanism choke, because the arbitrary token list material is
% enclosed in braces. The second argument of \cs{@@_if_in:nwwn} is
% most often empty. When the \meta{key} is found in the list,
% \cs{@@_if_in:N} receives \cs{s_@@} or \cs{s_obj_end}, and if it is
% found as the extra item, the function receives
% \cs{q_recursion_tail}, easily recognizable.
%
% Here, \cs{prop_map_function:NN} is not sufficient for the mapping,
% since it can only map a single token, and cannot carry the key that
% is searched for.
% \begin{macrocode}
\prg_new_conditional:Npnn \prop_if_in:Nn #1#2 { p , T , F , TF }
{
\exp_last_unbraced:Noo \@@_if_in:nwwn { \tl_to_str:n {#2} } #1
\@@_pair:wn \tl_to_str:n {#2} \s_@@ { }
\q_recursion_tail
\__prg_break_point:
}
\cs_new:Npn \@@_if_in:nwwn #1#2 \@@_pair:wn #3 \s_@@ #4
{
\str_if_eq_x:nnTF {#1} {#3}
{ \@@_if_in:N }
{ \@@_if_in:nwwn {#1} }
}
\cs_new:Npn \@@_if_in:N #1
{
\if_meaning:w \q_recursion_tail #1
\prg_return_false:
\else:
\prg_return_true:
\fi:
\__prg_break:
}
\cs_generate_variant:Nn \prop_if_in_p:Nn { NV , No }
\cs_generate_variant:Nn \prop_if_in_p:Nn { c , cV , co }
\cs_generate_variant:Nn \prop_if_in:NnT { NV , No }
\cs_generate_variant:Nn \prop_if_in:NnT { c , cV , co }
\cs_generate_variant:Nn \prop_if_in:NnF { NV , No }
\cs_generate_variant:Nn \prop_if_in:NnF { c , cV , co }
\cs_generate_variant:Nn \prop_if_in:NnTF { NV , No }
\cs_generate_variant:Nn \prop_if_in:NnTF { c , cV , co }
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \subsection{Recovering values from property lists with branching}
%
% \begin{macro}[TF, tested = m3prop004]
% {
% \prop_get:NnN, \prop_get:NVN, \prop_get:NoN,
% \prop_get:cnN, \prop_get:cVN, \prop_get:coN
% }
% Getting the value corresponding to a key, keeping track of whether
% the key was present or not, is implemented as a conditional (with
% side effects). If the key was absent, the token list is not altered.
% \begin{macrocode}
\prg_new_protected_conditional:Npnn \prop_get:NnN #1#2#3 { T , F , TF }
{
\@@_split:NnTF #1 {#2}
{
\tl_set:Nn #3 {##2}
\prg_return_true:
}
{ \prg_return_false: }
}
\cs_generate_variant:Nn \prop_get:NnNT { NV , No }
\cs_generate_variant:Nn \prop_get:NnNF { NV , No }
\cs_generate_variant:Nn \prop_get:NnNTF { NV , No }
\cs_generate_variant:Nn \prop_get:NnNT { c , cV , co }
\cs_generate_variant:Nn \prop_get:NnNF { c , cV , co }
\cs_generate_variant:Nn \prop_get:NnNTF { c , cV , co }
% \end{macrocode}
% \end{macro}
%
% \subsection{Mapping to property lists}
%
% \begin{macro}[tested = m3prop003]
% {
% \prop_map_function:NN, \prop_map_function:Nc,
% \prop_map_function:cN, \prop_map_function:cc
% }
% \begin{macro}[aux]{\@@_map_function:Nwwn}
% The fastest way to do a recursion here is to use an
% \cs{if_meaning:w} test: the keys are strings, and thus cannot match
% the marker \cs{q_recursion_tail}. A special case to note is when
% the key |#3| is empty: then \cs{q_recursion_tail} is compared to
% \cs{exp_after:wN}, also different. Note that |#2| can only consist
% of \cs{s_@@} and/or \cs{s_obj_end}.
% \begin{macrocode}
\cs_new:Npn \prop_map_function:NN #1#2
{
\exp_last_unbraced:NNo \@@_map_function:Nwwn #2 #1
\@@_pair:wn \q_recursion_tail \s_@@ { }
\__prg_break_point:Nn \prop_map_break: { }
}
\cs_new:Npn \@@_map_function:Nwwn #1#2 \@@_pair:wn #3 \s_@@ #4
{
\if_meaning:w \q_recursion_tail #3
\exp_after:wN \prop_map_break:
\fi:
#1 {#3} {#4}
\@@_map_function:Nwwn #1
}
\cs_generate_variant:Nn \prop_map_function:NN { Nc }
\cs_generate_variant:Nn \prop_map_function:NN { c , cc }
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}[tested = m3prop003]{\prop_map_inline:Nn, \prop_map_inline:cn}
% Mapping in line requires a nesting level counter. Store the current
% definition of \cs{@@_pair:wn}, and define it anew. At the end of
% the loop, revert to the earlier definition. Note that besides pairs
% of the form \cs{@@_pair:wn} \meta{key} \cs{s_@@} \Arg{value}, there
% are a leading and a trailing tokens, but both are equal to
% \cs{scan_stop:}, hence have no effect in such inline mapping.
% \begin{macrocode}
\cs_new_protected:Npn \prop_map_inline:Nn #1#2
{
\cs_gset_eq:cN
{ __prg_map_ \int_use:N \g__prg_map_int :wn } \@@_pair:wn
\int_gincr:N \g__prg_map_int
\cs_gset:Npn \@@_pair:wn ##1 \s_@@ ##2 {#2}
#1
\__prg_break_point:Nn \prop_map_break:
{
\int_gdecr:N \g__prg_map_int
\cs_gset_eq:Nc \@@_pair:wn
{ __prg_map_ \int_use:N \g__prg_map_int :wn }
}
}
\cs_generate_variant:Nn \prop_map_inline:Nn { c }
% \end{macrocode}
% \end{macro}
%
% \begin{macro}[tested = m3prop003]{\prop_map_break:}
% \begin{macro}[tested = m3prop003]{\prop_map_break:n}
% The break statements are based on the general \cs{__prg_map_break:Nn}.
% \begin{macrocode}
\cs_new_nopar:Npn \prop_map_break:
{ \__prg_map_break:Nn \prop_map_break: { } }
\cs_new_nopar:Npn \prop_map_break:n
{ \__prg_map_break:Nn \prop_map_break: }
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \subsection{Viewing property lists}
%
% \begin{macro}[tested = m3show001]{\prop_show:N, \prop_show:c}
% Apply the general \cs{__msg_show_variable:Nnn}. Contrarily
% to sequences and comma lists, we use \cs{__msg_show_item:nn}
% to format both the key and the value for each pair.
% \begin{macrocode}
\cs_new_protected:Npn \prop_show:N #1
{
\__msg_show_variable:Nnn #1 { prop }
{ \prop_map_function:NN #1 \__msg_show_item:nn }
}
\cs_generate_variant:Nn \prop_show:N { c }
% \end{macrocode}
% \end{macro}
%
% \begin{macrocode}
%</initex|package>
% \end{macrocode}
%
% \end{implementation}
%
% \PrintIndex
|