Re: how to compare two macros in TeX?

[Rupert <rupert.debian@hotpop.com>]

On 19 Nov 2002 16:47:03 +0100
martin f krafft <madduck@debian.org> wrote:

> 
> let's say i have this in a TeX document:
> 
>   \def\variable{somevalue}
> 
> how can i use a switch or if statement, testing for this value?
> 

This compares the complete expansions of whatever you throw at it:

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\def\same#1#2{00\fi%
  \edef\tmpone{#1}%
  \edef\tmptwo{#2}%
  \ifx\tmpone\tmptwo}   

\def\variable{somevalue}

\if\same{\variable}{somevalue}
same\else diff\fi

\if\same{\variable}{typo}
same\else diff\fi

\if\same{typo}{typo}
same\else diff\fi

\bye
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

Rupert