long index(types::list<T> &seq, T const &x)
{
long index_value = seq.index(x);
if (index_value == seq.size())
throw types::ValueError(__builtin__::anonymous::str(x) +
" is not in list");
return index_value;
}
long index(types::list<T> &seq, T const& x) {
return seq.index(x);
}