change function's formals default values

Hello,

I'm passing a user defined function into my c code. Once this function
is in my c code, I'd like to iteratively change the values associated
with the parameters defined in the function's formal list then evaluate
the function using these newly set defaults (i.e., using lang1(fn)).

My question is, how do I simply change the value associated with each
parameter in this function's formal list. I have messed around with the
SET_FORMAL function but can't figure out how to change these values.

Thanks-

Andrew

Research Fellow
Department of Forest Resources
University of Minnesota
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Phone: (612) 624-1714
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