LaTeX3: forma elegante de reenviar argumentos (tokens, estrellas, adornos) a otro comando

Question

Me cuesta definir elegantemente un comando LaTeX3 y reenviar sus argumentos (en particular, estrellas, fichas, adornos) a otro comando. Supongo que podría hacerlo funcionar usando \expandonceo similar, pero supongo que hay una solución mejor.

MWE:

\documentclass[]{article}

\NewDocumentCommand{\mycommand}{st't-t.e_O{}m}{%
  I am a command called \IfBooleanT{#1}{with a star, }\IfBooleanT{#2}{with a prime, }\IfBooleanT{#3}{with a dash, }\IfBooleanT{#4}{with a dot, }\IfNoValueTF{#5}{}{with an underscore (#5), } with the optional argument ``#6'' and with the mandatory argument ``#7''.
}

%% This fails:
% \NewDocumentCommand{\mynewcommand}{st't-t.e_O{}m}{%
%   \mycommand\IfBooleanT{#1}{*}\IfBooleanT{#2}{'}\IfBooleanT{#3}{.}\IfBooleanT{#4}{_{#4}}[foo#5]{#6}%
% }

%% This fails:
% \NewDocumentCommand{\mynewcommand}{st't-t.e_O{}m}{%
%   \mycommand#1#2#3#4[foo#5]{#6}%
% }

\begin{document}
\mycommand'_{below text}[I am optional]{yes}

How to define a new command so that mynewcommand behave like mycommand except that it prepends a string like "foo" in front of the optional argument?

% \mynewcommand*'-._{below text}[I am optional]{yes}


\end{document}

Answer 1

¿Es esto lo que quieres? Creo que debes haber pasado por alto el argumento #3(el argumento s-) \mynewcommand, así que me tomé la libertad de agregarlo.

\documentclass[]{article}

\NewDocumentCommand{\mycommand}{st't-t.e_O{}m}{%
  I am a command called \IfBooleanT{#1}{with a star, }\IfBooleanT{#2}{with a prime, }\IfBooleanT{#3}{with a dash, }\IfBooleanT{#4}{with a dot, }\IfValueT{#5}{with an underscore (#5), } with the optional argument ``#6'' and with the mandatory argument ``#7''.
}

% This works:
 \NewDocumentCommand{\mynewcommand}{st't-t.e_O{}m}{%
   \expandafter\mycommand\expanded{\IfBooleanT{#1}{*}\IfBooleanT{#2}{'}\IfBooleanT{#3}{-}\IfBooleanT{#4}{.}\IfValueT{#5}{\unexpanded{_{#5}}}\unexpanded{[foo#6]{#7}}}%
 }

%% This fails:
% \NewDocumentCommand{\mynewcommand}{st't-t.e_O{}m}{%
%   \mycommand#1#2#3#4[foo#5]{#6}%
% }

\begin{document}
\mycommand'_{below text}[I am optional]{yes}

How to define a new command so that mynewcommand behave like mycommand except that it prepends a string like "foo" in front of the optional argument?

\mynewcommand*'-._{below text}[I am optional]{yes}


\end{document}

Answer 2

No. No es \NewDocumentCommandpara eso.

De todos modos, primero corrija los argumentos en \mynewcommand: su lista está eliminada.

\documentclass[]{article}

\NewDocumentCommand{\mycommand}{st't-t.e_O{}m}{%
  I am a command called
  \IfBooleanT{#1}{with a star, }%
  \IfBooleanT{#2}{with a prime, }%
  \IfBooleanT{#3}{with a dash, }%
  \IfBooleanT{#4}{with a dot, }%
  \IfValueT{#5}{with an underscore (#5), }
  with the optional argument ``#6'' and with the mandatory argument ``#7''.
}

\NewDocumentCommand{\mynewcommand}{st't-t.e{_}O{}m}{%
  \expanded{%
    \mycommand
    \IfBooleanT{#1}{*}%
    \IfBooleanT{#2}{'}%
    \IfBooleanT{#3}{-}%
    \IfBooleanT{#4}{.}
    \IfValueT{#5}{_{\unexpanded{#5}}}%
    [foo\unexpanded{#6}]%
    {\unexpanded{#7}}%
  }%
}


\begin{document}
\mycommand'_{below text}[I am optional]{yes}

How to define a new command so that mynewcommand behave like mycommand except that it prepends a string like "foo" in front of the optional argument?

\mynewcommand*'-._{below text}[I am optional]{yes}

\end{document}