arg() crashes the emulator

[salvomic]

I use this code mostly for distinguish between reals, vectors and lists and it works.
It should works also with functions and expressions.
In my program for Fourier Coefficient I treat 2 arguments and a third, optional.
I was advised to use it so:
IF argc=3 THEN f:= zip('unapply', f, argv(2));
program accepts both fourcoeff(fun, k) or fourcoeff(expr, var, k)
So user can input a function or an expression and a parameter for the variable and in both case program get the correct input...

I hope this could be helpful for you.

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see the thread here in the Forum (by me, Han, Tim, Snorre...)