Re: [NTG-context] Determing if the argument is one character or not

On Wed, 4 Feb 2009, Wolfgang Schuster wrote:

Am 04.02.2009 um 00:11 schrieb Aditya Mahajan:

...

I want to write a macro which behaves differently depending on whether its argumet is a single character or not.

\MACRO[a] should give $X_{a}$ \MACRO[a:b] should give $X_{[a:b]}$

Any hints on how to do this?

To test for the number argument use \counttoken(s) and to check if the string contains a ":" use \doifinstring/\doifinstringelse.

Thanks. For the moment, I will go with Hans's solution, since it is much simpler. Aditya