Am 25.01.2012 um 20:20 schrieb Philipp A.:

2012/1/25 Hans Hagen <pragma@wxs.nl>
\ifmmode

thanks. that was obvious…

$\StrikeMe{x}$

unfortunately this does the same as my tikz version: it exits math mode:

$\StrikeMe{\ifmmode math mode! \else no math mode :( \fi} \ifmmode math mode. \else wat \fi$

returns

no math mode :( math mode.

\framed puts the content in a \hbox and when you put a \hbox in a math environment the text in the box is typeset in text mode, this feature is used for the \text command. To get now the content of the \StrikeMe command in math mode a different definition.

\defineframed[StrikeMeFrame][background=strikeme,frame=off,offset=0pt,location=low,backgroundcolor=blue]

\define[1]\StrikeMe
  {\ifmmode
     \StrikeMeFrame{$#1$}%
   \else
     \StrikeMeFrame{#1}%
   \fi}

Wolfgang