Pop a complex number from the stack
int SLang_pop_complex (double *re, double *im)
SLang_pop_complex pops a complex number from the stack and
returns it via the parameters re and im as the real and
imaginary parts of the complex number, respectively. This function
automatically converts objects of type SLANG_DOUBLE_TYPE and
SLANG_INT_TYPE to SLANG_COMPLEX_TYPE, if necessary.
It returns zero upon sucess, or -1 upon error setting
SLang_Error accordingly.
SLang_pop_integer, SLang_pop_double, SLang_push_complex