How to override TeX dollars?

Question

I've read about \renewenvironment and \let commands but they are intended to work with classic commands TeX commands that start with a slash.

And I cannot find any example of overriding $ and $$ any how.

Is it possible?

Welcome to TeX.sx! Can you please add more details about what you're trying to achieve? — egreg, Apr 04 '13 at 21:06
Is this a duplicate of http://tex.stackexchange.com/questions/59980/can-i-redefine-the-dollar?rq=1 ? — Christian Feuersänger, Apr 04 '13 at 21:07

Ian Thompson · Answer 1 · 2013-04-04T21:38:03.003

6

You need to change the category code (catcode) of $ to something other than math shift.

\documentclass{article}
\begin{document}
\catcode`$=12
This costs many $$.
\end{document}

You can have all sorts of fun changing catcodes; here the catcode of u is changed to math shift.

\documentclass{article}
\begin{document}
\catcode`u=3
an equation. another equation
\end{document}

See chapter 2 of the free book TeX by Topic for more details. Be warned, though - changing catcodes is a risky business that is likely to break just about everything.

edited Apr 04 '13 at 21:38

answered Apr 04 '13 at 21:07

Ian Thompson

43,767

Out of curiosity (and for completeness): what is the catcode for math shift? If I'd like to use another character as math shift, how would I do it? – Tomas Aschan Apr 04 '13 at 21:08
2

It is 3. There is a list in TeX by Topic. – Ian Thompson Apr 04 '13 at 21:10
There’s also one in our catcodes tag wiki. – doncherry Apr 04 '13 at 21:18
@IanThompson I'd assign catcode 12 and not 11 to $ – egreg Apr 04 '13 at 21:34
@egreg --- indeed; fixed. – Ian Thompson Apr 04 '13 at 21:37

How to override TeX dollars?

1 Answers1