Aditya Mahajan wrote:

Hi,

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?

\def\MACRO[#1#2]% {\doifelsenothing{#2} {$X_{#1}$} {$X_{[#1#2]}$}} ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com | www.pragma-pod.nl -----------------------------------------------------------------

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. Wolfgang