shicks / inlinedef Goto Github PK

@sasozivanovic

I'd like to conditionally define parts of a macro depending on whether the debug mode is on or not. So, assuming \newif\ifdebug, I'd like to write

\Inline\def\macro{%
   ...
   \ExpandIfT{debug}{debug code }%
   ...
}

With inlinedef, I'm almost there. I can define \ExpandIfT (and its cousins \ExpandIfF and \ExpandIfTF not shown here), and then expand them manually using \MultiExpand:

\def\ExpandIfT#1{%
   \csname
     \csname if#1\endcsname
       @firstofone%
     \else
       @gobble%
     \fi
   \endcsname
}

\newif\ifdebug
\debugtrue

\Inline\def\macro{%
   ...
   \MultiExpand{3}{\ExpandIfT{debug}{debug code }}%
   ...
}

However, being able to use \ExpandIf(T)(F) directly has quite an appeal to me. I investigated inlinedef code a bit and it doesn't seem very hard to extend it to accept user defined keywords inside an \Inline definition. I have drafted a patch makes this possible.

The idea is to define user commands in terms of \Expand, or, more probably, \MultiExpand. When a user keyword is encountered in the definition, it is expanded by the \UnsafeExpand mechanism.

I hope you will consider accepting the extension into the package.

From @sasozivanovic, in reference to #1:

I also need this mechanism with \csdef.

\expandafter\Inline\expandafter\def\csname macro\endcsname ...{...}

does not work, because \csname macro\endcsname lets \macro to \relax and then \Inline chokes on \meaning\macro.

The workaround, which I believe would be beneficial anyway, could be to have a command (named something like) \InlineNoDef, which would take a single argument, do its expansion magic, and execute it. This would readily support \csdef, though without redefinitions, but I must selfishly admit I'm not interested in those at this time.

Again, I attach the relevant definition which simply skips over the gruesome job of parsing the macro prefixes and parameters ;-)

I guess my example of usage also answers a question from the documentation: no, \Inline should not be \outer.

\def\forest@newarray@#1{%
  ...
  \InlineNoDef{\csdef{#1bottompop}##1{% ##1 = receiving cs
    \Expand{\csname#1ifempty\endcsname}{%
      \forest@array@empty@error{#1}%
    }{%
      \letcs##1{#1\the\Expand{\csname#1M\endcsname}}%
      \ExpandIfT{forest@temp}\global
      \advance\Expand{\csname#1M\endcsname 1}%
    }%
  }}%
  ...
}