% \iffalse
%
% advice.edtx (this is not a .dtx file; to produce a .dtx, process it with edtx2dtx)
%
%% This file is a part of Advice, a TeX package implementing a generic
%% framework for extending the functionality of selected commands and
%% environments, available at https://ctan.org/pkg/advice and
%% https://github.com/sasozivanovic/advice.
%%
%% Copyright (c) 2023- Saso Zivanovic <saso.zivanovic@guest.arnes.si>
%% (Sa\v{s}o \v{Z}ivanovi\'{c})
%%
%% This work may be distributed and/or modified under the conditions of the
%% LaTeX Project Public License, either version 1.3c of this license or (at
%% your option) any later version. The latest version of this license is in
%% https://www.latex-project.org/lppl.txt and version 1.3c or later is part of
%% all distributions of LaTeX version 2008 or later.
%%
%% This work has the LPPL maintenance status `maintained'.
%% The Current Maintainer of this work is Saso Zivanovic.
%%
%% The files belonging to this work and covered by LPPL are listed in
%% (<texmf>/doc/generic/advice/)FILES.
%
% \fi
%
% \begin{macrocode}
%
% \relax
%
%<*main>
%<latex>\ProvidesPackage{advice}[2024/03/15 v1.1.1 Extend commands and environments]
%<context>%D \module[
%<context>%D file=t-advice.tex,
%<context>%D version=1.1.1,
%<context>%D title=Advice,
%<context>%D subtitle=Extend commands and environments,
%<context>%D author=Saso Zivanovic,
%<context>%D date=2024-03-15,
%<context>%D copyright=Saso Zivanovic,
%<context>%D license=LPPL,
%<context>%D ]
%<context>\writestatus{loading}{ConTeXt User Module / advice}
%<context>\unprotect
%<context>\startmodule[advice]
% \paragraph{Required packages}
%<plain,context>\input miniltx
%<latex>\RequirePackage{collargs}
%<plain>\input collargs
%<context>\input t-collargs
% In \hologo{LaTeX}, we also require |xparse|. Even though
% |\NewDocumentCommand| and friends are integrated into the \hologo{LaTeX}
% kernel, |\GetDocumentCommandArgSpec| is only available through |xparse|.
%<latex>\RequirePackage{xparse}
%
% \subsubsection{Installation into a keypath}
%
% \begin{handlerskey}{.install advice}
% This handler installs the advising mechanism into the handled path, which
% we shall henceforth also call the (advice) namespace.
\pgfkeys{
/handlers/.install advice/.code={%
\edef\auto@install@namespace{\pgfkeyscurrentpath}%
\def\advice@install@setupkey{advice}%
\def\advice@install@activation{immediate}%
\pgfqkeys{/advice/install}{#1}%
\expanded{\noexpand\advice@install
{\auto@install@namespace}%
{\advice@install@setupkey}%
{\advice@install@activation}%
}%
},
% \end{handlerskey}
%
% \begin{adviceinstallkey}{setup key,activation}
% These keys can be used in the argument of |.install advice| to configure
% the installation. By default, the setup key is |advice| and |activation| is
% |immediate|.
/advice/install/.cd,
setup key/.store in=\advice@install@setupkey,
activation/.is choice,
activation/.append code=\def\advice@install@activation{#1},
activation/immediate/.code={},
activation/deferred/.code={},
}
% \end{adviceinstallkey}
%
% |#1| is the installation keypath (in Memoize, |/mmz|); |#2| is the setup key
% name (in Memoize, |auto|, and this is why we document it as such); |#3| is
% the initial activation regime.
\def\advice@install#1#2#3{%
% Switch to the installation keypath.
\pgfqkeys{#1}{%
% \begin{key}{auto, auto csname, auto key, auto', auto csname', auto key'}
% These keys submit a command or environment to advising. The
% namespace is hard-coded into these keys via |#1|; their arguments are
% the command/environment (cs)name, and setup keys belonging to path
% \meta{installation keypath}|/\meta{setup key name}|.
% \indentmacrocode
#2/.code 2 args={%
% \noindentmacrocode
% Call the internal setup macro, wrapping the received keylist into a
% |pgfkeys| invocation.
\AdviceSetup{#1}{#2}{##1}{\pgfqkeys{#1/#2}{##2}}%
% Activate if not already activated (this can happen when updating the
% configuration). Note we don't call |\advice@activate| directly, but use
% the public keys; in this way, activation is automatically deferred if
% so requested. (We don't use |\pgfkeysalso| to allow |auto| being called
% from any path.)
\pgfqkeys{#1}{try activate, activate={##1}}%
},
% A variant without activation.
#2'/.code 2 args={%
\AdviceSetup{#1}{#2}{##1}{\pgfqkeys{#1/#2}{##2}}%
},
#2 csname/.style 2 args={
#2/.expand once=\expandafter{\csname ##1\endcsname}{##2},
},
#2 csname'/.style 2 args={
#2'/.expand once=\expandafter{\csname ##1\endcsname}{##2},
},
#2 key/.style 2 args={
#2/.expand once=%
\expandafter{\csname pgfk@##1/.@cmd\endcsname}%
{collector=\advice@pgfkeys@collector,##2},
},
#2 key'/.style 2 args={
#2'/.expand once=%
\expandafter{\csname pgfk@##1/.@cmd\endcsname}%
{collector=\advice@pgfkeys@collector,##2},
},
% \end{key}
%
% \begin{key}{activation}
% This key, residing in the installation keypath, forwards the request to
% the |/advice| path |activation| subkeys, which define |activate| and
% friends in the installation keypath. Initially, the activation regime
% is whatever the user has requested using the |.install advice| argument
% (here |#3|).
activation/.style={/advice/activation/##1={#1}},
activation=#3,
% \end{key}
%
% \begin{key}{activate deferred}
% The deferred activations are collected in this style, see
% section~ref{sec:code:advice:activation} for details.
activate deferred/.code={},
% \end{key}
%
% \begin{key}{activate csname, deactivate csname}
% For simplicity of implementation, the |csname| versions of |activate|
% and |deactivate| accept a single \meta{csname}. This way, they can be
% defined right away, as they don't change with the type of activation
% (immediate vs.\ deferred).
activate csname/.style={activate/.expand once={\csname##1\endcsname}},
deactivate csname/.style={deactivate/.expand once={\csname##1\endcsname}},
% \end{key}
%
% \begin{key}{activate key, deactivate key}
% (De)activation of |pgfkeys| keys. Accepts a list of key names, requires
% full key names.
activate key/.style={activate@key={#1/activate}{##1}},
deactivate key/.style={activate@key={#1/deactivate}{##1}},
activate@key/.code n args=2{%
\def\advice@temp{}%
\def\advice@do####1{%
\eappto\advice@temp{,\expandonce{\csname pgfk@####1/.@cmd\endcsname}}}%
\forcsvlist\advice@do{##2}%
\pgfkeysalso{##1/.expand once=\advice@temp}%
},
% \end{key}
%
% The rest of the keys defined below reside in the |auto| subfolder of the
% installation keypath.
#2/.cd,
%
% \begin{mmzautokey}{run conditions, outer handler, bailout handler, collector,
% args, collector options, clear collector options, raw collector options,
% clear raw collector options, inner handler, options, clear options}
% These keys are used to setup the handling of the command or
% environment. The storage macros (|\AdviceRunConditions| etc.) have
% public names as they also play a crucial role in the handler
% definitions, see section~\ref{sec:code:advice:handle}.
% \indentmacrocode[-0.5em]
run conditions/.store in=\AdviceRunConditions,
bailout handler/.store in=\AdviceBailoutHandler,
outer handler/.store in=\AdviceOuterHandler,
collector/.store in=\AdviceCollector,
collector options/.code={\appto\AdviceCollectorOptions{,##1}},
clear collector options/.code={\def\AdviceCollectorOptions{}},
raw collector options/.code={\appto\AdviceRawCollectorOptions{##1}},
clear raw collector options/.code={\def\AdviceRawCollectorOptions{}},
args/.store in=\AdviceArgs,
inner handler/.store in=\AdviceInnerHandler,
options/.code={\appto\AdviceOptions{,##1}},
clear options/.code={\def\AdviceOptions{}},
% \noindentmacrocode
% A user-friendly way to set |options|: any unknown key is an option.
.unknown/.code={%
\eappto{\AdviceOptions}{,\pgfkeyscurrentname={\unexpanded{##1}}}%
},
% The default values of the keys, which equal the initial values for
% commands, as assigned by |\advice@setup@init@command|.
run conditions/.default=\AdviceRuntrue,
bailout handler/.default=\relax,
outer handler/.default=\AdviceCollector,
collector/.default=\advice@CollectArgumentsRaw,
collector options/.value required,
raw collector options/.value required,
args/.default=\advice@noargs,
inner handler/.default=\advice@error@noinnerhandler,
options/.value required,
% \end{mmzautokey}
%
% \begin{mmzautokey}{reset}
% This key resets the advice settings to their initial values, which
% depend on whether we're handling a command or environment.
reset/.code={\csname\advice@setup@init@\AdviceType\endcsname},
% \end{mmzautokey}
%
% \begin{mmzautokey}{after setup}
% The code given here will be executed once we exit the setup group.
% |integrated driver| of Memoize uses it to declare a conditional.
after setup/.code={\appto\AdviceAfterSetup{##1}},
% \end{mmzautokey}
%
% In \hologo{LaTeX}, we finish the installation by submitting |\begin|; the
% submission is funky, because the run conditions handler actually hacks
% the standard handling procedure. Note that if |\begin| is not
% activated, environments will not be handled, and that the automatic
% activation might be deffered.
%<latex>#1/#2=\begin{run conditions=\advice@begin@rc},
}%
}
%
%
% \subsubsection{Submitting a command or environment}
% \label{sec:code:advice:setup}
%
% \begin{macro}{\AdviceSetup,\AdviceName,\AdviceType}
% Macro |\advice@setup| is called by key |auto| to submit a command or
% environment to advising. It receives four arguments: |#1| is the
% installation keypath / storage namespace: |#2| is the name of the setup
% key; |#3| is the submitted command or environment; |#4| is the setup code
% (which is only grabbed by |\advice@setup@i|).
%
% Executing this macro defines macros |\AdviceName|, holding the control
% sequence of the submitted command or the environment name, and |\AdviceType|,
% holding |command| or |environment|; they are used to set up some initial
% values, and may be used by user-defined keys in the |auto| path, as well
% (see |/mmz/auto/noop| for an example). The macro then performs internal
% initialization, and finally calls the second part, |\advice@setup@i|, with
% the command's \emph{storage} name as the first argument.
%
% This macro also serves as the programmer's interface to |auto|, the idea
% being that an advanced user may write code |#4| which defined the settings
% macros (|\AdviceOuterHandler| etc.) without deploying |pgfkeys|. (Also note
% that activation at the end only occurs through the |auto| interface.)
\def\AdviceSetup#1#2#3{%
% Open a group, so that we allow for embedded |auto| invocations.
\begingroup
\def\AdviceName{#3}%
\advice@def@AdviceCsname
% Command, complain, or environment?
\collargs@cs@cases{#3}{%
\def\AdviceType{command}%
\advice@setup@init@command
\advice@setup@i{#3}{#1}{#3}%
}{%
\advice@error@advice@notcs{#1/#2}{#3}%
}{%
\def\AdviceType{environment}%
\advice@setup@init@environment
%<latex>\advice@setup@i{#3}%
%<plain>\expandafter\advice@setup@i\expandafter{\csname #3\endcsname}%
%<context>\expandafter\advice@setup@i\expandafter{\csname start#3\endcsname}%
{#1}{#3}%
}%
}
% The arguments of |\advice@setup@i| are a bit different than for
% |\advice@setup|, because we have inserted the storage name as |#1| above, and
% we lost the setup key name |#2|. Here, |#2| is the installation keypath /
% storage namespace, |#3| is the submitted command or environment; and |#4| is
% the setup code.
%
% What is the difference between the storage name (|#1|) and the command\slash
% environment name (|#3|, and also the contents of |\AdviceName|), and why do we
% need both? For commands, there is actually no difference; for example, when
% submitting command |\foo|, we end up with |#1|=|#3|=|\foo|. And there is
% also no difference for \hologo{LaTeX} environments; when submitting
% environment |foo|, we get |#1|=|#3|=|foo|. But in \hologo{plainTeX},
% |#1|=|\foo| and |#3|=|foo|, and in \hologo{ConTeXt}, |#1|=|\startfoo| and
% |#3|=|foo| --- which should explain the guards and |\expandafter|s above.
%
% And why both |#1| and |#3|? When a handled command is executed, it loads its
% configuration from a macro determined by the storage namespace and the
% (|\string|ified) storage name, e.g.\ |/mmz| and |\foo|. In \hologo{plainTeX}
% and \hologo{ConTeXt}, each environment is started by a dedicated command,
% |\foo| or |\startfoo|, so these control sequences (|\string|ified) must act
% as storage names. (Not so in \hologo{LaTeX}, where an environment
% configuration is loaded by |\begin|'s handler, which can easily work with
% storage name |foo|. Even more, having |\foo| as an environment storage
% name would conflict with the storage name for the (environment-internal)
% command |\foo| --- yes, we can submit either |foo| or |\foo|, or both, to
% advising.)
\def\advice@setup@i#1#2#3#4{%
% Load the current configuration of the handled command or environment --- if
% it exists.
\advice@setup@init@i{#2}{#1}%
\advice@setup@init@I{#2}{#1}%
\def\AdviceAfterSetup{}%
% Apply the setup code/keys.
#4%
% Save the resulting configuration. This closes the group, because the config
% is saved outside it.
\advice@setup@save{#2}{#1}%
}
% \end{macro}
%
% \paragraph{Initialize} the configuration of a command or environment. Note
% that the default values of the keys equal the initial values for commands.
% Nothing would go wrong if these were not the same, but it's nice that the
% end-user can easily revert to the initial values.
\def\advice@setup@init@common{%
\def\AdviceRunConditions{\AdviceRuntrue}%
\def\AdviceBailoutHandler{\relax}%
\def\AdviceOuterHandler{\AdviceCollector}%
\def\AdviceCollector{\advice@CollectArgumentsRaw}%
\def\AdviceCollectorOptions{}%
\def\AdviceInnerHandler{\advice@error@noinnerhandler}%
\def\AdviceOptions{}%
}
\def\advice@setup@init@command{%
\advice@setup@init@common
\def\AdviceRawCollectorOptions{}%
\def\AdviceArgs{\advice@noargs}%
}
\def\advice@setup@init@environment{%
\advice@setup@init@common
\edef\AdviceRawCollectorOptions{%
\noexpand\collargsEnvironment{\AdviceName}%
% When grabbing an environment body, the end-tag will be included. This
% makes it possible to have the same inner handler for commands and
% environments.
\noexpand\collargsEndTagtrue
}%
\def\AdviceArgs{+b}%
}
% We need to initialize |\AdviceOuterHandler| etc.\ so that |\advice@setup@store|
% will work.
\advice@setup@init@command
%
% \paragraph.{The configuration storage}
%
% The remaining macros in this subsection deal with the configuration storage
% space, which is set up in a way to facilitate fast loading during the
% execution of handled commands and environments.
%
% The configuration of a command or environment is stored in two parts: the
% first stage settings comprise the run conditions, the bailout handler and the
% outer handler; the second stage settings contain the rest. When a handled
% command is invoked, only the first stage settings are immediately loaded, for
% speed; the second stage settings are only loaded if the run conditions are
% satisfied.
%
% \begin{macro}{\advice@init@i,\advice@init@I}
% The two-stage settings are stored in control sequences
% |\advice@i|\meta{namespace}|//|\meta{storage name} and
% |\advice@I|\meta{namespace}|//|\meta{storage name}, respectively, and
% accessed using macros |\advice@init@i| and |\advice@init@I|.
%
% Each setting storage macro contains a sequence of items, where each item is
% either of form |\def\AdviceSetting|\marg{value}. This allows us store
% multiple settings in a single macro (rather than define each
% control-sequence-valued setting separately, which would use more string
% memory), and also has the consequence that we don't require the handlers to
% be defined when submitting a command (whether that's good or bad could be
% debated: as things stand, any typos in handler declarations will only yield
% an error once the handled command is executed).
\def\advice@init@i#1#2{\csname advice@i#1//\string#2\endcsname}
\def\advice@init@I#1#2{\csname advice@I#1//\string#2\endcsname}
% We make a copy of these for setup; the originals might be swapped for
% tracing purposes.
\let\advice@setup@init@i\advice@init@i
\let\advice@setup@init@I\advice@init@I
% \end{macro}
%
% \begin{macro}{\advice@setup@save}
% To save the configuration at the end of the setup, we construct the storage
% macros out of |\AdviceRunConditions| and friends. Stage-one contains only
% |\AdviceRunConditions| and |\AdviceBailoutHandler|, so that
% |\advice@handle| can bail out as quickly as possible if the run conditions
% are not met.
\def\advice@setup@save#1#2{%
\expanded{%
% Close the group before saving. Note that |\expanded| has already expanded
% the settings macros.
\endgroup
\noexpand\csdef{advice@i#1//\string#2}{%
\def\noexpand\AdviceRunConditions{\expandonce\AdviceRunConditions}%
\def\noexpand\AdviceBailoutHandler{\expandonce\AdviceBailoutHandler}%
}%
\noexpand\csdef{advice@I#1//\string#2}{%
\def\noexpand\AdviceOuterHandler{\expandonce\AdviceOuterHandler}%
\def\noexpand\AdviceCollector{\expandonce\AdviceCollector}%
\def\noexpand\AdviceRawCollectorOptions{%
\expandonce\AdviceRawCollectorOptions}%
\def\noexpand\AdviceCollectorOptions{\expandonce\AdviceCollectorOptions}%
\def\noexpand\AdviceArgs{\expandonce\AdviceArgs}%
\def\noexpand\AdviceInnerHandler{\expandonce\AdviceInnerHandler}%
\def\noexpand\AdviceOptions{\expandonce\AdviceOptions}%
}%
\expandonce{\AdviceAfterSetup}%
}%
}
% \end{macro}
% \label{sec:code:advice:activation}
%
% \begin{advicekey}{activation/immediate, activation/deferred}
% These two subkeys of |/advice/activation| install the immediate and the
% deferred activation code into the installation keypath. They are invoked
% by key \meta{installation keypath}|/activation=|\meta{type}.
%
% Under the deferred activation regime, the commands are not (de)activated
% right away. Rather, the (de)activation calls are collected in style
% |activate deferred|, which should be executed by the installation keypath
% owner, if and when they so desire. (Be sure to switch to
% |activation=immediate| before executing |activate deferred|, otherwise the
% activation will only be deferred once again.)
\pgfkeys{
/advice/activation/deferred/.style={
#1/activate/.style={%
activate deferred/.append style={#1/activate={##1}}},
#1/deactivate/.style={%
activate deferred/.append style={#1/deactivate={##1}}},
#1/force activate/.style={%
activate deferred/.append style={#1/force activate={##1}}},
#1/try activate/.style={%
activate deferred/.append style={#1/try activate={##1}}},
},
% \end{advicekey}
%
% \begin{key}{activate, deactivate, force activate, try activate}
% The ``real,'' immediate |activate| and |deactivate| take a comma-separated
% list of commands or environments and (de)activate them. If |try activate|
% is in effect, no error is thrown upon failure. If |force activate| is in
% effect, activation proceeds even if we already had the original definition;
% it does not apply to deactivation. These conditionals are set to false
% after every invocation of key |(de)activate|, so that they only apply to
% the immediately following |(de)activate|. (|#1| below is the
% \meta{namespace}; |##1| is the list of commands to be (de)activated.)
/advice/activation/immediate/.style={
#1/activate/.code={%
\forcsvlist{\advice@activate{#1}}{##1}%
\advice@activate@forcefalse
\advice@activate@tryfalse
},
#1/deactivate/.code={%
\forcsvlist{\advice@deactivate{#1}}{##1}%
\advice@activate@forcefalse
\advice@activate@tryfalse
},
#1/force activate/.is if=advice@activate@force,
#1/try activate/.is if=advice@activate@try,
},
}
\newif\ifadvice@activate@force
\newif\ifadvice@activate@try
% \end{key}
%
% \begin{macro}{\advice@original@csname,\advice@original@cs,\AdviceGetOriginal}
% Activation replaces the original meaning of the handled command with our
% definition. We store the original definition into control sequence
% |\advice@o|\meta{namespace}|//|\meta{storage name} (with a |\string|ified
% \meta{storage name}). Internally, during (de)activation and handling, we
% access it using |\advice@original@csname| and |\advice@original@cs|. Publicly
% it should always be accessed by |\AdviceGetOriginal|, which returns the
% argument control sequence if that control sequence is not handled.
%
% Using the internal command outside the handling context, we could fall
% victim to scenario such as the following. When we memoize something
% containing a |\label|, the produced cc-memo contains code eventually
% executing the original |\label|. If we called the original |\label| via
% the internal macro there, and the user |deactivate|d |\label| on a
% subsequent compilation, the cc-memo would not call |\label| anymore, but
% |\relax|, resulting in a silent error. Using |\AdviceGetOriginal|, the
% original |\label| will be executed even when not activated.
%
% However, not all is bright with |\AdviceGetOriginal|. Given an activated
% control sequence (|#2|), a typo in the namespace argument (|#1|) will lead
% to an infinite loop upon the execution of |\AdviceGetOriginal|. In the
% manual, we recommend defining a namespace-specific macro to avoid such
% typos.
\def\advice@original@csname#1#2{advice@o#1//\string#2}
\def\advice@original@cs#1#2{\csname advice@o#1//\string#2\endcsname}
\def\AdviceGetOriginal#1#2{%
\ifcsname advice@o#1//\string#2\endcsname
\expandonce{\csname advice@o#1//\string#2\expandafter\endcsname\expandafter}%
\else
\unexpanded\expandafter{\expandafter#2\expandafter}%
\fi
}
% \end{macro}
%
% \begin{macro}{\AdviceCsnameGetOriginal}
% A version of |\AdviceGetOriginal| which accepts a control sequence name as
% the second argument.
\begingroup
\catcode`\/=0
\catcode`\\=12
/gdef/advice@backslash@other{\}%
/endgroup
\def\AdviceCsnameGetOriginal#1#2{%
\ifcsname advice@o#1//\advice@backslash@other#2\endcsname
\expandonce{\csname advice@o#1//\advice@backslash@other#2\expandafter\endcsname
\expandafter}%
\else
\expandonce{\csname#2\expandafter\endcsname\expandafter}%
\fi
}
% \end{macro}
%
% \begin{macro}{\advice@activate,\advice@deactivate}
% These macros execute either the command, or the environment (de)activator.
\def\advice@activate#1#2{%
\collargs@cs@cases{#2}%
{\advice@activate@cmd{#1}{#2}}%
{\advice@error@activate@notcsorenv{}{#1}}%
{\advice@activate@env{#1}{#2}}%
}
\def\advice@deactivate#1#2{%
\collargs@cs@cases{#2}%
{\advice@deactivate@cmd{#1}{#2}}%
{\advice@error@activate@notcsorenv{de}{#1}}%
{\advice@deactivate@env{#1}{#2}}%
}
% \end{macro}
%
% \begin{macro}{\advice@activate@cmd}
% We are very careful when we're activating a command, because activating
% means rewriting its original definition. Configuration by |auto| did not
% touch the original command; activation will. So, the leitmotif of this
% macro: safety first. (|#1| is the namespace, and |#2| is the command to be
% activated.)
\def\advice@activate@cmd#1#2{%
% Is the command defined?
\ifdef{#2}{%
% Yes, the command is defined. Let's see if it's safe to activate it.
% We'll do this by checking whether we have its original definition in our
% storage. If we do, this means that we have already activated the
% command. Activating it twice would lead to the loss of the original
% definition (because the second activation would store our own
% redefinition as the original definition) and consequently an infinite
% loop (because once --- well, if --- the handler tries to invoke the
% original command, it will execute itself all over).
\ifcsdef{\advice@original@csname{#1}{#2}}{%
% Yes, we have the original definition, so the safety check failed, and
% we shouldn't activate again. Unless \dots\ how does its current
% definition look like?
\advice@if@our@definition{#1}{#2}{%
% Well, the current definition of the command matches what we would put
% there ourselves. The command is definitely activated, and we refuse
% to activate again, as that would destroy the original definition.
\advice@activate@error@activated{#1}{#2}{Command}{already}%
}{%
% We don't recognize the current definition as our own code (despite
% the fact that we have surely activated the commmand before, given the
% result of the first safety check). It appears that someone else was
% playing fast and loose with the same command, and redefined it after
% our activation. (In fact, if that someone else was another instance
% of Advice, from another namespace, forcing the activation will result
% in the loss of the original definition and the infinite loop.) So it
% \emph{should} be safe to activate it (again) \dots\ but we won't do
% it unless the user specifically requested this using |force
% activate|. Note that without |force activate|, we would be stuck in
% this branch, as we could neither activate (again) nor deactivate the
% command.
\ifadvice@activate@force
\advice@activate@cmd@do{#1}{#2}%
\else
\advice@activate@error@activated{#1}{#2}{Command}{already}%
\fi
}%
}{%
% No, we don't have the command's original definition, so it was not yet
% activated, and we may activate it.
\advice@activate@cmd@do{#1}{#2}%
}%
}{%
\advice@activate@error@undefined{#1}{#2}{Command}{}%
}%
}
% \end{macro}
%
% \begin{macro}{\advice@deactivate@cmd}
% The deactivation of a command follows the same template as activation, but
% with a different logic, and of course a different effect. In order to
% deactivate a command, both safety checks discussed above must be satisfied:
% we must have the command's original definition, \emph{and} our redefinition
% must still reside in the command's control sequence --- the latter
% condition prevents overwriting someone else's redefinition with the
% original command. As both conditions must be unavoidably fulfilled, |force
% activate| has no effect in deactivation (but |try activate| has).
\def\advice@deactivate@cmd#1#2{%
\ifdef{#2}{%
\ifcsdef{\advice@original@csname{#1}{#2}}{%
\advice@if@our@definition{#1}{#2}{%
\advice@deactivate@cmd@do{#1}{#2}%
}{%
\advice@deactivate@error@changed{#1}{#2}%
}%
}{%
\advice@activate@error@activated{#1}{#2}{Command}{not yet}%
}%
}{%
\advice@activate@error@undefined{#1}{#2}{Command}{de}%
}%
}
% \end{macro}
%
% \begin{macro}{\advice@if@our@definition}
% This macro checks whether control sequence |#2| was already activated (in
% namespace |#1|) in the sense that its current definition contains the code
% our activation would put there: |\advice@handle{#1}{#2}| (protected).
\def\advice@if@our@definition#1#2{%
\protected\def\advice@temp{\advice@handle{#1}{#2}}%
\ifx#2\advice@temp
\expandafter\@firstoftwo
\else
\expandafter\@secondoftwo
\fi
}
% \end{macro}
%
% \begin{macro}{\advice@activate@cmd@do}
% This macro saves the original command, and redefines its control sequence.
% Our redefinition must be |\protected| --- even if the original command
% wasn't fragile, our replacement certainly is. (Note that as we require
% \hologo{eTeX} anyway, we don't have to pay attention to \hologo{LaTeX}'s
% robust commands by redefining their ``inner'' command. Protecting our
% replacement suffices.)
\def\advice@activate@cmd@do#1#2{%
\cslet{\advice@original@csname{#1}{#2}}#2%
\protected\def#2{\advice@handle{#1}{#2}}%
\PackageInfo{advice (#1)}{Activated command "\string#2"}%
}
% \end{macro}
%
% \begin{macro}{\advice@deactivate@cmd@do}
% This macro restores the original command, and removes its definition from
% our storage --- this also serves as a signal that the command is not
% activated anymore.
\def\advice@deactivate@cmd@do#1#2{%
\letcs#2{\advice@original@csname{#1}{#2}}%
\csundef{\advice@original@csname{#1}{#2}}%
\PackageInfo{advice (#1)}{Deactivated command "\string#2"}%
}
% \end{macro}
%
%
% \subsubsection{Executing a handled command}
% \label{sec:code:advice:handle}
%
% \begin{macro}{\advice@handle}
% An invocation of this macro is what replaces the original command and runs
% the whole shebang. The system is designed to bail out as quickly as
% necessary if the run conditions are not met (plus \hologo{LaTeX}'s |\begin|
% will receive a very special treatment for this reason).
%
% We first check the run conditions, and bail out if they are not satisfied.
% Note that only the stage-one config is loaded at this point. It sets up
% the following macros (while they are public, neither the end user not the
% installation keypath owner should ever have to use them):
%
% \begin{itemize}
% \item \PrintMainMacro{\AdviceRunConditions} executes |\AdviceRuntrue| if the
% command should be handled; set by |run conditions|.
% \item \PrintMainMacro{\AdviceBailoutHandler} will be executed if the
% command will not be handled, after all; set by |bailout handler|.
% \end{itemize}
\def\advice@handle#1#2{%
\advice@init@i{#1}{#2}%
\AdviceRunfalse
\AdviceRunConditions
\advice@handle@rc{#1}{#2}%
}
% \end{macro}
%
% \begin{macro}{\advice@handle@rc}
% We continue the handling in a new macro, because this is the point where
% the handler for |\begin| will hack into the regular flow of events.
\def\advice@handle@rc#1#2{%
\ifAdviceRun
\expandafter\advice@handle@outer
\else
% Bailout is simple: we first execute the handler, and then the original command.
\AdviceBailoutHandler
\expandafter\advice@original@cs
\fi
{#1}{#2}%
}
% \end{macro}
%
% \begin{macro}{\advice@handle@outer}
% To actually handle the command, we first setup some macros:
%
% \begin{itemize}
% \item \PrintMainMacro{\AdviceNamespace} holds the installation keypath /
% storage name space.
% \item \PrintMainMacro{\AdviceName} holds the control sequence of the handled
% command, or the environment name.
% \item \PrintMainMacro{\AdviceReplaced} holds the ``substituted'' code. For
% commands, this is the same as |\AdviceName|. For environment |foo|, it
% equals |\begin{foo}| in \hologo{LaTeX}, |\foo| in \hologo{plainTeX} and
% |\startfoo| in \hologo{ConTeXt}.
% \item \PrintMainMacro{\AdviceOriginal} executes the original definition of
% the handled command or environment.
% \end{itemize}
\def\advice@handle@outer#1#2{%
\def\AdviceNamespace{#1}%
\def\AdviceName{#2}%
\advice@def@AdviceCsname
\let\AdviceReplaced\AdviceName
\def\AdviceOriginal{\AdviceGetOriginal{#1}{#2}}%
% We then load the stage-two settings. This defines the following macros:
% \begin{itemize}
% \item \PrintMainMacro{\AdviceOuterHandler} will effectively replace the
% command, if it will be handled; set by |outer handler|.
% \item \PrintMainMacro{\AdviceCollector} collects the arguments of the handled
% command, perhaps consulting |\AdviceArgs| to learn about its argument
% structure.
% \item \PrintMainMacro{\AdviceRawCollectorOptions} contains the options which
% will be passed to the argument collector, in the ``raw'' format.
% \item \PrintMainMacro{\AdviceCollectorOptions} contains the additional,
% user-specified options which will be passed to the argument collector.
% \item \PrintMainMacro{\AdviceArgs} contains the |xparse|-style argument
% specification of the command, or equals |\advice@noargs| to signal that
% command was defined using |xparse| and that the argument specification
% should be retrieved automatically.
% \item \PrintMainMacro{\AdviceInnerHandler} is called by the argument
% collector once it finishes its work. It receives all the collected
% arguments as a single (braced) argument.
% \item \PrintMainMacro{\AdviceOptions} holds options which may be used by the
% outer or the inner handler; Advice does not need or touch
% them.
% \end{itemize}
\advice@init@I{#1}{#2}%
% All prepared, we execute the outer handler.
\AdviceOuterHandler
}
\def\advice@def@AdviceCsname{%
\begingroup
\escapechar=-1
\expandafter\expandafter\expandafter\endgroup
\expandafter\expandafter\expandafter\def
\expandafter\expandafter\expandafter\AdviceCsname
\expandafter\expandafter\expandafter{\expandafter\string\AdviceName}%
}
% \end{macro}
%
% \begin{macro}{\ifAdviceRun}
% This conditional is set by the run conditions macro to signal whether we
% should run the outer (true) or the bailout (false) handler.
\newif\ifAdviceRun
% \end{macro}
%
% \begin{macro}{\advice@CollectArgumentsRaw}
% This is the default collector, which will collect the argument using
% CollArgs' command |\CollectArgumentsRaw|. It will provide that command
% with:
% \begin{itemize}
% \item the collector options, given in the raw format:
% \begin{itemize}
% \item the caller (|\collargsCaller|),
% \item the raw options (|\AdviceRawCollectorOptions|), and
% \item the user options (|\AdviceRawCollectorOptions|, wrapped in
% |\collargsSet|;
% \end{itemize}
% \item the argument specification |\AdviceArgs| of the handled command; and
% \item the inner handler |\AdviceInnerHandler| to execute after collecting the
% arguments; the inner handler receives the collected arguments as a single
% braced argument.
% \end{itemize}
% \hangindent=0pt If the argument specification is not defined (either the user
% did not set it, or has reset it by writing |args| without a value), it is
% assumed that the handled command was defined by |xparse| and |\AdviceArgs|
% will be retrieved by |\GetDocumentCommandArgSpec|.
% \begin{listingregion}{_advice-CollectArgumentsRaw.tex}
\def\advice@CollectArgumentsRaw{%
\AdviceIfArgs{}{%
\expandafter\GetDocumentCommandArgSpec\expandafter{\AdviceName}%
\let\AdviceArgs\ArgumentSpecification
}%
\expanded{%
\noexpand\CollectArgumentsRaw{%
\noexpand\collargsCaller{\expandonce\AdviceName}%
\expandonce\AdviceRawCollectorOptions
\ifdefempty\AdviceCollectorOptions{}{%
\noexpand\collargsSet{\expandonce\AdviceCollectorOptions}%
}%
}%
{\expandonce\AdviceArgs}%
{\expandonce\AdviceInnerHandler}%
}%
}
% \end{listingregion}
% \end{macro}
%
% \begin{macro}{\AdviceIfArgs}
% If the value of |args| is ``real'', i.e.\ an |xparse| argument
% specification, execute the first argument. If |args| was set to the
% special value |\advice@noargs|, signaling a command defined by
% |\NewDocumentCommand| or friends, execute the second argument. (Ok, in
% reality anything other than |\advice@noargs| counts as real ``real''.)
\def\advice@noargs@text{\advice@noargs}
\def\AdviceIfArgs{%
\ifx\AdviceArgs\advice@noargs@text
\expandafter\@secondoftwo
\else
\expandafter\@firstoftwo
\fi
}
% \end{macro}
%
% \begin{macro}{\advice@pgfkeys@collector}
% A |pgfkeys| collector is very simple: the sole argument of the any key
% macro, regardless of the argument structure of the key, is everything up to
% |\pgfeov|.
\def\advice@pgfkeys@collector#1\pgfeov{%
\AdviceInnerHandler{#1}%
}
% \end{macro}
%
% \subsubsection{Environments}
% \label{sec:code:advice:environments}
%
% \begin{macro}{\advice@activate@env,\advice@deactivate@env}
% Things are simple in \hologo{TeX} and \hologo{ConTeXt}, as their environments
% are really commands. So rather than activating environment name |#2|, we
% (de)activate command |\#2| or |\start#2|, depending on the format.
%<*plain,context>
\def\advice@activate@env#1#2{%
\expanded{%
\noexpand\advice@activate@cmd{#1}{\expandonce{\csname
%<context>start%
#2\endcsname}}%
}%
}
\def\advice@deactivate@env#1#2{%
\expanded{%
\noexpand\advice@deactivate@cmd{#1}{\expandonce{\csname
%<context>start%
#2\endcsname}}%
}%
}
%</plain,context>
%
% We activate commands by redefining them; that's the only way to do it. But
% we won't activate a \hologo{LaTeX} environment |foo| by redefining command
% |\foo|, where the user's definition for the start of the environment actually
% resides, as such a redefinition would be executed too late, deep within the
% group opened by |\begin|, following many internal operations and public
% hooks. We handle \hologo{LaTeX} environments by defining an outer handler
% for |\begin| (consequently, \hologo{LaTeX} environment support can be
% (de)activated by the user by saying (|de|)|activate=\begin|), and
% activating an environment will be nothing but setting a mark, by
% defining a dummy control sequence |\advice@original@csname{#1}{#2}|,
% which that handler will inspect. Note that |force activate| has no
% effect here.
%<*latex>
\def\advice@activate@env#1#2{%
\ifcsdef{\advice@original@csname{#1}{#2}}{%
\advice@activate@error@activated{#1}{#2}{Environment}{already}%
}{%
\csdef{\advice@original@csname{#1}{#2}}{}%
\PackageInfo{advice (#1)}{Activated environment "#2"}%
}%
}
\def\advice@deactivate@env#1#2{%
\ifcsdef{\advice@original@csname{#1}{#2}}{%
\csundef{\advice@original@csname{#1}{#2}}{}%
}{%
\advice@activate@error@activated{#1}{#2}{Environment}{not yet}%
\PackageInfo{advice (#1)}{Dectivated environment "#2"}%
}%
}
% \end{macro}
%
% \begin{macro}{\advice@begin@rc}
% This is the handler for |\begin|. It is very special, for speed. It is
% meant to be declared as the run conditions component, and it hacks into
% the normal flow of handling. It knows that after executing the run
% conditions macro, |\advice@handle| eventually (the tracing info may
% interrupt here as |#1|) continues by
% |\advice@handle@rc|\marg{namespace}\marg{handled control sequence}, so it
% grabs all these (|#2| is the \meta{namespace} and |#3| is the
% \meta{handled control sequence}, i.e.\ |\begin|) plus the environment
% name (|#4|).
\def\advice@begin@rc#1\advice@handle@rc#2#3#4{%
% We check whether environment |#4| is activated (in namespace |#2|) by
% inspecting whether activation dummy is defined. If it is not, we execute
% the original |\begin| (|\advice@original@cs{#2}{#3}|), followed by the
% environment name (|#4|). Note that we \emph{don't} execute the
% environment's bailout handler here: we haven't checked its run conditions
% yet, as the environment is simply not activated.
\ifcsname\advice@original@csname{#2}{#4}\endcsname
\expandafter\advice@begin@env@rc
\else
\expandafter\advice@original@cs
\fi
{#2}{#3}{#4}%
}
% \end{macro}
%
% \begin{macro}{\advice@begin@env@rc}
% Starting from this point, we essentially replicate the workings of
% |\advice@handle|, adapted to \hologo{LaTeX} environments.
\def\advice@begin@env@rc#1#2#3{%
% We first load the stage-one configuration for environment |#3| in namespace
% |#1|.
\advice@init@i{#1}{#3}%
% This defined |\AdviceRunConditions| for the environment. We can now check its
% run conditions. If they are not satisfied, we bail out by executing the
% environment's bailout handler followed by the original |\begin|
% (|\advice@original@cs{#1}{#2}|) plus the environment name (|#3|).
\AdviceRunConditions
\ifAdviceRun
\expandafter\advice@begin@env@outer
\else
\AdviceBailoutHandler
\expandafter\advice@original@cs
\fi
{#1}{#2}{#3}%
}
% \end{macro}
%
% \begin{macro}{\advice@begin@env@outer}
% We define the macros expected by the outer handler, see
% |\advice@handle@outer|, load the second-stage configuration, and execute the
% environment's outer handler.
\def\advice@begin@env@outer#1#2#3{%
\def\AdviceNamespace{#1}%
\def\AdviceName{#3}%
\let\AdviceCsname\advice@undefined
\def\AdviceReplaced{#2{#3}}%
\def\AdviceOriginal{\AdviceGetOriginal{#1}{#2}{#3}}%
\advice@init@I{#1}{#3}%
\AdviceOuterHandler
}
%</latex>
% \end{macro}
%
%
% \subsubsection{Error messages}
%
% Define error messages for the entire package. Note that
% |\advice@(de)activate@error@...| implement |try activate|.
%
\def\advice@activate@error@activated#1#2#3#4{%
\ifadvice@activate@try
\else
\PackageError{advice (#1)}{#3 "\string#2" is #4 activated}{}%
\fi
}
\def\advice@activate@error@undefined#1#2#3#4{%
\ifadvice@activate@try
\else
\PackageError{advice (#1)}{%
#3 "\string#2" you are trying to #4activate is not defined}{}%
\fi
}
\def\advice@deactivate@error@changed#1#2{%
\ifadvice@activate@try
\else
\PackageError{advice (#1)}{The definition of "\string#2" has changed since we
have activated it. Has somebody overridden our command?}{If you have tried
to deactivate so that you could immediately reactivate, you may want to try
"force activate".}%
\fi
}
\def\advice@error@advice@notcs#1#2{%
\PackageError{advice}{The first argument of key "#1" should be either a single
control sequence or an environment name, not "#2"}{}%
}
\def\advice@error@activate@notcsorenv#1#2{%
\PackageError{advice}{Each item in the value of key "#1activate" should be
either a control sequence or an environment name, not "#2".}{}%
}
\def\advice@error@storecs@notcs#1#2{%
\PackageError{advice}{The value of key "#1" should be a single control sequence,
not "\string#2"}{}%
}
\def\advice@error@noinnerhandler#1{%
\PackageError{advice (\AdviceNamespace)}{The inner handler for
"\expandafter\string\AdviceName" is not defined}{}%
}
% \subsubsection{Tracing}
%
% We implement tracing by adding the tracing information to the handlers after
% we load them. So it is the handlers themselves which, if and when they are
% executed, will print out that this is happening.
%
% \begin{macro}{\AdviceTracingOn,\AdviceTracingOff}
% Enable and disable tracing.
\def\AdviceTracingOn{%
\let\advice@init@i\advice@trace@init@i
\let\advice@init@I\advice@trace@init@I
}
\def\AdviceTracingOff{%
\let\advice@init@i\advice@setup@init@i
\let\advice@init@I\advice@setup@init@I
}
% \end{macro}
% \begin{macro}{\advice@typeout,\advice@trace}
% The tracing output routine; the typeout macro depends on the format. In
% \hologo{LaTeX}, we use stream |\@unused|, which is guaranteed to be
% unopened, so that the output will go to the terminal and the log.
% \hologo{ConTeXt}, we don't muck about with write streams but simply use Lua
% function |texio.write_nl|. In \hologo{plainTeX}, we use either Lua or the
% stream, depending on the engine; we use a high stream number 128 although
% the good old 16 would probably work just as well.
%<plain>\ifdefined\luatexversion
%<!latex>\long\def\advice@typeout#1{\directlua{texio.write_nl("\luaescapestring{#1}")}}
%<plain>\else
%<latex>\def\advice@typeout{\immediate\write\@unused}
%<plain>\def\advice@typeout{\immediate\write128}
%<plain>\fi
\def\advice@trace#1{\advice@typeout{[tracing advice] #1}}
% \end{macro}
% \begin{macro}{\advice@trace@init@i,\advice@trace@init@I}
% Install the tracing code.
\def\advice@trace@init@i#1#2{%
\advice@trace{Advising \detokenize\expandafter{\string#2} (\detokenize{#1})}%
\advice@trace{\space\space Original command meaning:
\expandafter\expandafter\expandafter\meaning\advice@original@cs{#1}{#2}}%
\advice@setup@init@i{#1}{#2}%
\edef\AdviceRunConditions{%
% We first execute the original run conditions, so that we can show the
% result.
\expandonce\AdviceRunConditions
\noexpand\advice@trace{\space\space
Executing run conditions:
\detokenize\expandafter{\AdviceRunConditions}
-->
\noexpand\ifAdviceRun true\noexpand\else false\noexpand\fi
}%
}%
\edef\AdviceBailoutHandler{%
\noexpand\advice@trace{\space\space
Executing bailout handler:
\detokenize\expandafter{\AdviceBailoutHandler}}%
\expandonce\AdviceBailoutHandler
}%
}
\def\advice@trace@init@I#1#2{%
\advice@setup@init@I{#1}{#2}%
\edef\AdviceOuterHandler{%
\noexpand\advice@trace{\space\space
Executing outer handler:
\detokenize\expandafter{\AdviceOuterHandler}}%
\expandonce\AdviceOuterHandler
}%
\edef\AdviceCollector{%
\noexpand\advice@trace{\space\space
Executing collector:
\detokenize\expandafter{\AdviceCollector}}%
\noexpand\advice@trace{\space\space\space\space
Argument specification:
\detokenize\expandafter{\AdviceArgs}}%
\noexpand\advice@trace{\space\space\space\space
Options:
\detokenize\expandafter{\AdviceCollectorOptions}}%
\noexpand\advice@trace{\space\space\space\space
Raw options:
\detokenize\expandafter{\AdviceRawCollectorOptions}}%
% Collargs' |return| complicates tracing of the received argument. We put
% the code for remembering its value among the raw collector options. The
% default is 0; it is needed when we're using a collector other that
% |\CollectArguments|, the assumption being that external collectors will
% always return the collected arguments braced.
\unexpanded{%
\gdef\advice@collargs@return{0}%
\appto\AdviceRawCollectorOptions{\advice@remember@collargs@return}%
}%
\expandonce\AdviceCollector
}%
\edef\advice@inner@handler@trace@do{%
\noexpand\advice@trace{\space\space
Executing inner handler:
\detokenize\expandafter{\AdviceInnerHandler}}%
% When this macro is executed, the received arguments are waiting for us in
% |\toks0|.
\noexpand\advice@trace{\space\space\space\space
Received arguments\noexpand\advice@inner@handler@trace@printcollargsreturn:
\noexpand\detokenize\noexpand\expandafter{\unexpanded{\the\toks0}}}%
\noexpand\advice@trace{\space\space\space\space
Options:
\detokenize\expandafter{\AdviceOptions}}%
\expandonce{\AdviceInnerHandler}%
}%
\def\AdviceInnerHandler{\advice@inner@handler@trace}%
}
\def\advice@remember@collargs@return{%
\global\let\advice@collargs@return\collargsReturn
}
% This is the entry point into the tracing inner handler. It will either get
% the received arguments as a braced argument (when Collargs' |return=0|), or
% from |\collargsArgs| otherwise. We don't simply always inspect
% |\collargsArgs| because foreign argument collectors will not use this token
% register; the assumption is that they will always return the collected
% arguments braced.
\def\advice@inner@handler@trace{%
\ifnum\advice@collargs@return=0
\expandafter\advice@inner@handler@trace@i
\else
\expandafter\advice@inner@handler@trace@ii
\fi
}
\def\advice@inner@handler@trace@i#1{%
\toks0={#1}%
\advice@inner@handler@trace@do{#1}%
}
\def\advice@inner@handler@trace@ii{%
\expandafter\toks\expandafter0\expandafter{\the\collargsArgs}%
\advice@inner@handler@trace@do
}
\def\advice@inner@handler@trace@printcollargsreturn{%
\ifnum\advice@collargs@return=0
\else
\space(collargs return=%
\ifcase\advice@collargs@return braced\or plain\or no\fi
)%
\fi
}
% \end{macro}
%<plain>\resetatcatcode
%<context>\stopmodule
%<context>\protect
%</main>
%
% \subsubsection{The \TikZ; collector}
% \label{sec:code:advice:tikz}
%
% In this section, we implement the argument collector for command |\tikz|,
% which has idiosyncratic syntax, see \PGFmanual{12.2.2}:
% \begin{itemize}
% \item |\tikz|\meta{animation spec}|[|\meta{options}|]{|\meta{picture code}|}|
% \item |\tikz|\meta{animation spec}|[|\meta{options}|]|\meta{picture command}|;|
% \end{itemize}
% where \meta{animation spec} =
% (|:|\meta{key}|={|\meta{value}|}|)*.
%
% The \TikZ; code resides in a special file. It is meant to be |\input| at any
% time, so we need to temporarily assign |@| category code 11.
%<*tikz>
\edef\adviceresetatcatcode{\catcode`\noexpand\@\the\catcode`\@\relax}%
\catcode`\@=11
\def\AdviceCollectTikZArguments{%
% We initialize the token register which will hold the collected arguments,
% and start the collection. Nothing of note happens until \dots
\toks0={}%
\advice@tikz@anim
}
\def\advice@tikz@anim{%
\pgfutil@ifnextchar[{\advice@tikz@opt}{%
\pgfutil@ifnextchar:{\advice@tikz@anim@a}{%
\advice@tikz@code}}%]
}
\def\advice@tikz@anim@a#1=#2{%
\toksapp0{#1={#2}}%
\advice@tikz@anim
}
\def\advice@tikz@opt[#1]{%
\toksapp0{[#1]}%
\advice@tikz@code
}
\def\advice@tikz@code{%
\pgfutil@ifnextchar\bgroup\advice@tikz@braced\advice@tikz@single
}
\long\def\advice@tikz@braced#1{\toksapp0{{#1}}\advice@tikz@done}
\def\advice@tikz@single#1;{\toksapp0{#1;}\advice@tikz@done}
% \dots\ we finish collecting the arguments, when we execute the inner handler,
% with the (braced) collected arguments is its sole argument.
\def\advice@tikz@done{%
\expandafter\AdviceInnerHandler\expandafter{\the\toks0}%
}
\adviceresetatcatcode
%</tikz>
% \end{macrocode}
%
% Local Variables:
% TeX-engine: luatex
% TeX-master: "doc/memoize-code.tex"
% TeX-auto-save: nil
% End: