I looked in 'proc' macro and wonder about the symbol 'first@args'. What is this used for ? Why should we need this ? I only found its use in 'endp' macro, just to construct and purge an empty macro like:
macro rstargs#first@args _% %_
rstargs all@args
purge rstargs#first@args
Can it erase these from the source file ?
Cheers,

The trick is deep here.
If "first@args" is equal to empty string (in case you define procedure with zero arguments) the first row will redefine the macro "rstargs" to empty macro that do nothing - so the next line "rstargs all@args" will do nothing too.
The third row purges the so defined macro.

Regards.

what a nice trick! Thank you V. much