} else if (lt == AO_SCHEME_STRING && rt == AO_SCHEME_STRING) {
int c = strcmp(ao_scheme_poly_string(left),
ao_scheme_poly_string(right));
} else if (lt == AO_SCHEME_STRING && rt == AO_SCHEME_STRING) {
int c = strcmp(ao_scheme_poly_string(left),
ao_scheme_poly_string(right));