26.5 Unordered associative containers [unord]
template <class P>
iterator insert(P&& obj);
Effects: Equivalent to: return emplace(std::forward<P>(obj));
Remarks: This signature shall not participate in overload resolution
unless is_constructible_v<value_type, P&&> is true.
template <class P>
iterator insert(const_iterator hint, P&& obj);
Effects: Equivalent to:
return emplace_hint(hint, std::forward<P>(obj));
Remarks: This signature shall not participate in overload resolution
unless is_constructible_v<value_type, P&&> is true.