Weird 'ProvidesPackage' vs 'newenvironment' macro expansion

Question

currently improving an existing package ('ditaa', based on ditaa0_9.jar) to add support for svg (implemented in ditaa-0.11.0-standalone.jar) yet I'm facing strange macro definition/expansion.

Basically I want to control the behavior of the 'ditaa' binary by adding support of its command line arguments that way (summed up) :

\ProvidesPackage{ditaa}
\RequirePackage[patch]{kvoptions}

% Support for https://github.com/stathissideris/ditaa
\DeclareBoolOption{A}               % Turns anti-aliasing off (-A or --no-antialias)
\DeclareBoolOption{noantialias}

\ProcessKeyvalOptions*

\newenvironment{ditaa}[3][\columnwidth]{
        % OPTION A <-----
        \def\ditaaoptA{\ifthenelse{\boolean{ditaa@A}}{-A }{\ifthenelse{\boolean{ditaa@noantialias}}{--no-antialias }{}}}

        % OPTION B <-----
        \ifthenelse{\boolean{ditaa@A}}{\def\ditaaoptA{-A }}{\ifthenelse{\boolean{ditaa@noantialias}}{\def\ditaaoptA{--no-antialias }}{\def\ditaaoptA{}}}

        \VerbatimOut{\ditaafile}}
    {\endVerbatimOut
        \immediate\write18{ditaa.jar \ditaaoptA "\ditaafile" "\ditaadir/\ditaastem.png"}    % <----- TITI
        \begin{figure}[H]
            \vdots      % because I'm lazy
        \end{figure}
        \ditaaoptA      % <----- TOTO
    }

Later...

\usepackage[A]{ditaa}

Ok, so as said, when OPTION A is used, TOTO displays the right argument (-A) but TITI fails because what is executed is something of the like :

runsystem(ditaa.jar \let \begingroup \let \begingroup \NROrg@begingroup \begingroup \def \protect \let \reserved@d = *\def \catcode `\ =5 \par )...executed.

However when using OPTION B, it works in both cases, YET it requires defining the same macro 3 times (with an empty variant) which is cumbersome to maintain and error prone.

Is there a way to get OPTION A (that is more elegant) to work no matter what ?

Thanks.

Answer 1

As Ulrike said in the comment, \ifthenelse is not expandable, so it doesn't work inside a \write (that is, you must evaluate it first, set \ditaaoptA accordingly, and then pass it to \write).

Here's a reimplementation using an expl3 bool variable instead, and l3keys2e to parse the keys.

I made the no-antialias key a .bool_set:N key. The effect of no-antialias and no-antialias=true is the same, and you can also use no-antialias=false. I made A a .meta key that redirects to no-antialias (I wouldn't use it, though, and would only provide no-antialias), so you only have one boolean rather than having to check two (sanitise early and your code gets way simpler). I also defined keys for your other variables.

Then to call ditaa.jar you just need:

\sys_shell_now:x
  {
    ditaa.jar~ % executable
    \bool_if:NT \l__ditaa_no_antialias_bool { --no-antialias ~ } % --no-antialias if the bool is true
    "\l__ditaa_outfile_tl" ~ % whatever these other two are :)
    "\l__ditaa_path_tl/\l__ditaa_path_tl.png"
  }

I also made the optional argument to the environment be a list of keys that you can pass in a per-environment basis, rather than having them fixed by the load-time options.

\begin{filecontents}[overwrite]{ditaa.sty}

\RequirePackage{l3keys2e}
\RequirePackage{fancyvrb}

\ProvidesExplPackage{ditaa}{2020-11-04}
  {v1.0}{Interface to ditaa}

\keys_define:nn { ditaa }
  {
    , no-antialias .bool_set:N = \l__ditaa_no_antialias_bool
    , no-antialias .default:n = true
    , no-antialias .initial:n = false
    , A .meta:n = { no-antialias }
    %
    , output-file .tl_set:N = \l__ditaa_outfile_tl
    , output-file .initial:n = { \c_sys_jobname_str-ditaa }
    %
    , path .tl_set:N = \l__ditaa_path_tl
    , path .initial:n = { \c_sys_jobname_str-path } % <- insert reasonable defaults
    , stem .tl_set:N = \l__ditaa_stem_tl
    , stem .initial:n = { \c_sys_jobname_str-stem } % <- insert reasonable defaults
    %
  }

\ProcessKeysOptions { ditaa }

\NewDocumentEnvironment { ditaa } { o m m }
  {
    \group_begin:
      \IfValueT{#1} { \keys_set:nn { ditaa } {#1} }
      \VerbatimOut { \l__ditaa_outfile_tl }
  }
  {
      \endVerbatimOut
      % \exp_args:Nx \tl_show:n
      \sys_shell_now:x
        {
          ditaa.jar~
          \bool_if:NT \l__ditaa_no_antialias_bool { --no-antialias ~ }
          "\l__ditaa_outfile_tl" ~
          "\l__ditaa_path_tl/\l__ditaa_path_tl.png"
        }
    \group_end:
  }

\end{filecontents}

\documentclass{article}

\usepackage[A]{ditaa}

\begin{document}

\begin{ditaa}{a}{b}
\end{ditaa}

\begin{ditaa}[no-antialias=false]{a}{b}
\end{ditaa}

\end{document}

Answer 2

Here's my full version with things commented out because not functional/testing :

% 'ditaa' package
%
% (c) Hiroshi Ukai
%
%% This program can be redistributed and/or modified under the terms
%% of the LaTeX Project Public License Distributed from CTAN archives
%% in directory macros/latex/base/lppl.txt.
%
\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{ditaa}
[2020/11/04 v0.11.0 LaTeX package for embedding ditaa style ascii art]

\RequirePackage{fancyvrb}
\RequirePackage{graphicx}
\RequirePackage{svg}
\RequirePackage{etoolbox}
\RequirePackage{xifthen}
\RequirePackage[debugshow,patch]{kvoptions}
%\RequirePackage[patch]{kvoptions}
%\RequirePackage{kvoptions-patch}

%\newcommand*{\ditaasetup}[1]{\setkeys{ditaa}{#1}}
\newcommand*{\ditaasetup}{\kvsetkeys{ditaa}}
\SetupKeyvalOptions{setkeys=\kvsetkeys}
%\SetupKeyvalOptions{family=ditaa, prefix=ditaa@, setkeys=\kvsetkeys}
%\SetupKeyvalOptions{}

% These options are defined at \usepackage[options]{ditaa} location, *not* at \begin[options]{ditaa}
% These options can be changed at "runtime" using the \ditaasetup{options} macro, though
\DeclareStringOption{imagepath}             % Path of the image
\DeclareStringOption[\columnwidth]{width}[\columnwidth]

% Support for https://github.com/stathissideris/ditaa
\DeclareBoolOption{A}                       % Turns anti-aliasing off
\DeclareBoolOption{noantialias}
\DeclareStringOption{b}[FFFFFF]             % The background colour of the image
\DeclareStringOption{background}[FFFFFF]
\DeclareBoolOption{d}                       % Renders the debug grid
\DeclareBoolOption{debug}
\DeclareBoolOption[true]{E}                 % Prevents the separation of common edges
\DeclareBoolOption{noseparation}
\DeclareStringOption{e}[utf-8]              % The encoding of the input file
\DeclareStringOption{encoding}[utf-8]
\DeclareBoolOption{h}                       % The input is an HTML file
\DeclareBoolOption{html}
\DeclareBoolOption{help}                    % Prints usage help
\DeclareBoolOption{o}                       % Image file is overwriten
\DeclareBoolOption{overwrite}
\DeclareBoolOption{r}                       % All corners to be rendered as round corners
\DeclareBoolOption{roundcorners}
\DeclareBoolOption{S}                       % Turns off the drop-shadow effect
\DeclareBoolOption{noshadows}
\DeclareStringOption{s}[1.0]                % Size of the rendered image
\DeclareStringOption{scale}[1.0]
\DeclareBoolOption{svg}                     % SVG image as destination file
\DeclareStringOption{svgfonturl}[]          % SVG font URL
\DeclareBoolOption{T}                       % Diagram rendered on a transparent background
\DeclareBoolOption{transparent}
\DeclareStringOption{t}[4]                  % Tabs interpreted as x spaces
\DeclareStringOption{tabs}[4]
\DeclareBoolOption{v}                       % Makes ditaa more verbose
\DeclareBoolOption{verbose}
\DeclareBoolOption{W}                       % Sides of parallelograms as fixed slope
\DeclareBoolOption{fixedslop}

\ProcessKeyvalOptions*
%\ProcessLocalKeyvalOptions*
%\ProcessKeyvalOptions{ditaa}

%@formatter:off (This line indicates IntelliJ that formatter should be off before this)
\newenvironment{ditaa}[3][\ditaa@width]
    {
        \def\ditaacaption{#2}
        \def\ditaastem{#3}
        \def\ditaadir{\ditaa@imagepath/ditaa}
        \def\ditaafile{\ditaadir/\ditaastem.ditaa}
        \def\ditaafigwidth{#1}
        % usepackage->program options ('-\/-' is de-ligaturing '--')

%       \def\ditaaoptA{\ifthenelse{\boolean{ditaa@A}}{-A}{\ifthenelse{\boolean{ditaa@noantialias}}{-\/-no-antialias}{}}}
%       \def\ditaaoptb{\ifdefstring{\ditaa@b}{}{\ifdefstring{\ditaa@background}{}{}{-\/-background \ditaa@background}}{-b \ditaa@b}}
%       \def\ditaaoptd{\ifthenelse{\boolean{ditaa@d}}{-d}{\ifthenelse{\boolean{ditaa@debug}}{-\/-debug}{}}}
%       \def\ditaaoptE{\ifthenelse{\boolean{ditaa@E}}{-E}{\ifthenelse{\boolean{ditaa@noseparation}}{-\/-no-separation}{}}}
%       \def\ditaaopte{\ifdefstring{\ditaa@e}{}{\ifdefstring{\ditaa@encoding}{}{}{-\/-encoding \ditaa@encoding}}{-b \ditaa@e}}
%       \def\ditaaopth{\ifthenelse{\boolean{ditaa@h}}{-h}{\ifthenelse{\boolean{ditaa@html}}{-\/-html}{}}}
%       \def\ditaaopthelp{\ifthenelse{\boolean{ditaa@help}}{-\/-help}{}}
%       \def\ditaaopto{\ifthenelse{\boolean{ditaa@o}}{-o}{\ifthenelse{\boolean{ditaa@overwrite}}{-\/-overwrite}{}}}
%       \def\ditaaoptr{\ifthenelse{\boolean{ditaa@r}}{-r}{\ifthenelse{\boolean{ditaa@roundcorners}}{-\/-round-corners}{}}}
%       \def\ditaaoptS{\ifthenelse{\boolean{ditaa@S}}{-S}{\ifthenelse{\boolean{ditaa@noshadows}}{-\/-no-shadows}{}}}
%       \def\ditaaopts{\ifdefstring{\ditaa@s}{}{\ifdefstring{\ditaa@scale}{}{}{-\/-scale \ditaa@scale}}{-s \ditaa@s}}
%       \def\ditaaoptsvg{\ifthenelse{\boolean{ditaa@svg}}{-\/-svg}{}}
%       \def\ditaaoptsvgext{\ifthenelse{\boolean{ditaa@svg}}{svg}{png}}
%       \def\ditaaoptsvgfonturl{\ifdefstring{\ditaa@svg-font-url}{}{}{-\/-svg-font-url \ditaa@svg-font-url}}
%       \def\ditaaoptT{\ifthenelse{\boolean{ditaa@T}}{-T}{\ifthenelse{\boolean{ditaa@transparent}}{-\/-transparent}{}}}
%       \def\ditaaoptt{\ifdefstring{\ditaa@t}{}{\ifdefstring{\ditaa@tabs}{}{}{-\/-tabs \ditaa@tabs}}{-t \ditaa@t}}
%       \def\ditaaoptv{\ifthenelse{\boolean{ditaa@v}}{-v}{\ifthenelse{\boolean{ditaa@verbose}}{-\/-verbose}{}}}
%       \def\ditaaoptW{\ifthenelse{\boolean{ditaa@W}}{-W}{\ifthenelse{\boolean{ditaa@fixedslop}}{-\/-fixed-slop}{}}}

        % \\def\\(ditaaopt[-\w]+)\{\\ifthenelse\{\\boolean\{(ditaa\@[-\w]+)\}\}\{([-\w]+)\}\{\\ifthenelse\{\\boolean\{(ditaa\@[-\w]+)\}\}\{-\\/-([-\w]+)\}\{\}\}\}
        % \\ifthenelse\{\\boolean\{\2\}\}\{\\def\\\1\{\3 \}\}\{\\ifthenelse\{\\boolean\{\4\}\}\{\\def\\\1\{-\\/-\5 \}\}\{\\\1\{\}\}\}

        % \\def\\(ditaaopt[-\w]+)\{\\ifdefstring\{\\(ditaa\@[-\w]+)\}\{\}\{\\ifdefstring\{\\(ditaa\@[-\w]+)\}\{\}\{\}\{-\\/-([-\w]+) \\\3\}\}\{-([-\w]+) \\\2\}\}
        % \\ifdefstring\{\\\2\}\{\}\{\\ifdefstring\{\\\3\}\{\}\{\\\1\{\}\}\{\\def\\\1\{-\\/-\4 \\\3 \}\}\}\{\\def\\\1\{-\5 \\\2 \}\}
        
        % \\def\\(ditaaopt[-\w]+)\{\\ifthenelse\{\\boolean\{(ditaa\@[-\w]+)\}\}\{-\\/-([-\w]+)\}\{\}\}
        % \\ifthenelse\{\\boolean\{\2\}\}\{\\def\\\1\{-\\/-\3 \}\}\{\\\1\{\}\}
        
        \ifthenelse{\boolean{ditaa@A}}{\def\ditaaoptA{-A }}{\ifthenelse{\boolean{ditaa@noantialias}}{\def\ditaaoptA{--no-antialias }}{\def\ditaaoptA{}}}
        \ifdefstring{\ditaa@b}{}{\ifdefstring{\ditaa@background}{}{\def\ditaaoptb{}}{\def\ditaaoptb{--background \ditaa@background }}}{\def\ditaaoptb{-b \ditaa@b }}
        \ifthenelse{\boolean{ditaa@d}}{\def\ditaaoptd{-d }}{\ifthenelse{\boolean{ditaa@debug}}{\def\ditaaoptd{--debug }}{\def\ditaaoptd{}}}
        \ifthenelse{\boolean{ditaa@E}}{\def\ditaaoptE{-E }}{\ifthenelse{\boolean{ditaa@noseparation}}{\def\ditaaoptE{--no-separation }}{\def\ditaaoptE{}}}
        \ifdefstring{\ditaa@e}{}{\ifdefstring{\ditaa@encoding}{}{\def\ditaaopte{}}{\def\ditaaopte{--encoding \ditaa@encoding }}}{\def\ditaaopte{-e \ditaa@e }}
        \ifthenelse{\boolean{ditaa@h}}{\def\ditaaopth{-h }}{\ifthenelse{\boolean{ditaa@html}}{\def\ditaaopth{--html }}{\def\ditaaopth{}}}
        \ifthenelse{\boolean{ditaa@help}}{\def\ditaaopthelp{--help }}{\def\ditaaopthelp{}}
        \ifthenelse{\boolean{ditaa@o}}{\def\ditaaopto{-o }}{\ifthenelse{\boolean{ditaa@overwrite}}{\def\ditaaopto{--overwrite }}{\def\ditaaopto{}}}
        \ifthenelse{\boolean{ditaa@r}}{\def\ditaaoptr{-r }}{\ifthenelse{\boolean{ditaa@roundcorners}}{\def\ditaaoptr{--round-corners }}{\def\ditaaoptr{}}}
        \ifthenelse{\boolean{ditaa@S}}{\def\ditaaoptS{-S }}{\ifthenelse{\boolean{ditaa@noshadows}}{\def\ditaaoptS{--no-shadows }}{\def\ditaaoptS{}}}
        \ifdefstring{\ditaa@s}{}{\ifdefstring{\ditaa@scale}{}{\def\ditaaopts{}}{\def\ditaaopts{--scale \ditaa@scale }}}{\def\ditaaopts{-s \ditaa@s }}
        \ifthenelse{\boolean{ditaa@svg}}{\def\ditaaoptsvg{--svg }}{\def\ditaaoptsvg{}}
        \ifthenelse{\boolean{ditaa@svg}}{\def\ditaaoptsvgext{svg}}{\def\ditaaoptsvgext{png}}
        \ifdefstring{\ditaa@svgfonturl}{}{\def\ditaaoptsvgfonturl{}}{\def\ditaaoptsvgfonturl{--svg-font-url "\ditaa@svgfonturl" }}
        \ifthenelse{\boolean{ditaa@T}}{\def\ditaaoptT{-T }}{\ifthenelse{\boolean{ditaa@transparent}}{\def\ditaaoptT{--transparent }}{\def\ditaaoptT{}}}
        \ifdefstring{\ditaa@t}{}{\ifdefstring{\ditaa@tabs}{}{\def\ditaaoptt{}}{\def\ditaaoptt{--tabs \ditaa@tabs }}}{\def\ditaaoptt{-t \ditaa@t }}
        \ifthenelse{\boolean{ditaa@v}}{\def\ditaaoptv{-v }}{\ifthenelse{\boolean{ditaa@verbose}}{\def\ditaaoptv{--verbose }}{\def\ditaaoptv{}}}
        \ifthenelse{\boolean{ditaa@W}}{\def\ditaaoptW{-W }}{\ifthenelse{\boolean{ditaa@fixedslop}}{\def\ditaaoptW{--fixed-slop }}{\def\ditaaoptW{}}}

        \VerbatimOut{\ditaafile}}
    {\endVerbatimOut
        \immediate\write18{ditaa.jar \ditaaoptA \ditaaoptb \ditaaoptd \ditaaoptE \ditaaopte \ditaaopth \ditaaopthelp \ditaaopto \ditaaoptr \ditaaoptS \ditaaopts \ditaaoptsvg \ditaaoptsvgfonturl \ditaaoptT \ditaaoptt \ditaaoptv \ditaaoptW "\ditaafile" "\ditaadir/\ditaastem.\ditaaoptsvgext"}
        \begin{figure}[H]
            \begin{center}
                \vspace{-1em}
                \ifditaa@svg
                    \includesvg[inkscapelatex=false, width=\ditaafigwidth]{\ditaadir/\ditaastem.svg}
                \else
                    \includegraphics[width=\ditaafigwidth]{\ditaadir/\ditaastem.png}
                \fi
                \vspace{-2em}
                \caption{\ditaacaption}
                \label{fig:\ditaastem}
                \vspace{-1.5em}
            \end{center}
        \end{figure}
    }
%@formatter:on (This line indicates IntelliJ that formatter should be off before this)
%--------------------------------------------------

\endinput
%%
%% End of file `ditaa.sty'.

Yeah, I also noticed that double-hyphens got 'eaten', so I read in another topic that '--' should be 'escaped' as '-\/-', yet while it works for OPTION A, it doesn't for OPTION B. Go figure...