General ⇒ setting variables inside of \rlap

[steve6390]

Hello!

Two questions about this code:
Why does rlap prevent me from setting a variable?
I need to set a variable from within rlap that is visible outside rlap, but how?

Code: Select all

\documentclass{article}
\newif\ifmycheck
\begin{document}
\rlap{\mychecktrue}
% \mychecktrue
\ifmycheck
Check 1 True!
\else
Check 1 False!   % always takes this path!
\fi
\end{document}

Thanks for any clues.
Regards,
-steve

[sommerfee]

Crosspost!

Matthew Leingang wrote there:

Changes within a group stay inside that group, and \rlap puts its argument inside an \hbox, therefore within its own group. So if you did:

Code: Select all

\rlap{\mychecktrue % group is still open!
% \mychecktrue
\ifmycheck
Check True!
\else
Check False!  
\fi}

You will get :"Check True!"

So you see that you did set the variable inside \rlap.

You want the changes to persist outside the group. So use the prefix \global:

Code: Select all

\rlap{\global\mychecktrue}
% \mychecktrue
\ifmycheck
Check True!
\else
Check False!  
\fi

That will result again in: "Check True!"