General ⇒ expl3 for dummies - internal function arguments

[erwann]

How would I expl3-ify the following code? Can I specify an internal function like 'cs_new:Npn my_foo #1|#2* ....'? I tried, it doesn't seem like it.

Code: Select all

\documentclass{minimal}
\usepackage{xparse}

\ExplSyntaxOn

\def\@foo#1|#2*{
	(#1)(#2)
}

\NewDocumentCommand \foo
{u{|}u{*}}
{
\@foo#1|#2*
}

\ExplSyntaxOff

\begin{document}

\foo a|b* % (a)(b)

\end{document}

[cgnieder]

Such so-called “delimited” arguments would count as weird (w):

Code: Select all

\documentclass{article}
\usepackage{xparse}
 
\ExplSyntaxOn
 
\cs_new_protected:Npn \mypackage_foo:ww #1|#2*
  { (#1)(#2) }
 
\NewDocumentCommand \foo {u{|}u{*}}
  { \mypackage_foo:ww #1|#2* }
 
\ExplSyntaxOff
 
\begin{document}
 
\foo a|b* % (a)(b)
 
\end{document}