On Thu, 23 Jul 2009, Wolfgang Schuster wrote:

Am 23.07.2009 um 17:05 schrieb Aditya Mahajan:

I think an easier thing to do will be to follow latex's style of \newcommand and \renewcommand. That is, all \definecommands should check if the macro is previously defined or not. If it is defined, issue a warning or an error.

There is \define and \redefine.

I know. What I am asking is that the core macros like \definedescription, \defineitemgroups, \definehead, which have the general form

\def\defineSOMETHING%
 {\dodoubleargument\dodefineSOMETHING}

\def\dodefineSOMETHING[#1][#2]%
 {\setvalue{#1}{\dododefineSOMETHING[#2]}

should do some check before the \setvalue. Maybe a universal solution will be to change \setvalue so that it uses \define (or a check like define) internally.