Member function pointer issue with standard library methods

Question

This question is spawned from
Passing a member function pointer to an overloaded class method into a template function.
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Answer 1

The problem isn't with the insert functions you showed in MySet. The problem is with one of the ones you omitted. Specifically:

template< class InputIt >
void insert( InputIt first, InputIt last );

From [temp.deduct.call]:

When P is a function type, pointer to function type, or pointer to member function type:
— If the argument is an overload set containing one or more function templates, the parameter is treated as a non-deduced context.

Since &std::set::insert is precisely such an overload set, the parameter is a non-deduced context and cannot be resolved. Your example of MySet does not contain a function template overload for insert, which is why it works fine. If you add one, you'll see that it will also fail to compile.