for (unsigned i=0; i<e.nops(); i++) {
ex r = e.op(i);
if (!r.info(info_flags::relation_equal)) {
- throw(std::invalid_argument("basic::subs(ex): argument must be a list or equations"));
+ throw(std::invalid_argument("basic::subs(ex): argument must be a list of equations"));
}
ls.append(r.op(0));
lr.append(r.op(1));