spice .func expansion?

I have an old version of spice3, and need to use some newer (I think PSpice) models with .func statements. I think that these are really just macros, and not real function calls. Has anyone written a program that would simply expand these out as full text, which would mostly convert this PSpice to spice3? I know this is possible, but my compiler construction class was a long time ago! I have tried doing this by hand, but there are so many nested functions that it is too error-prone.

Thanks!