Is there an equivalent of "typename" for template types?

Question

We have a template member function of the form:

template <template <class> class TT>
TT<some_type> foo() const;

Now, in an invocation context where TT is explicitly specified from a dependent name:

template <class T_other>
void bar()
{
    instance.foo<T_other::template_type>();
}

Visual Studio is able to compile the invocation. GCC complains:

error: dependent-name ‘SomeConcreteType::template_type’ is parsed as a non-type, but instantiation yields a type.

And advises to say typename SomeConcreteType::template_type. Which does not work, since SomeConcreteType::template_type is a template type, not a plain type.

• Is there a keyword that can be used here?
• Another way to make this accepted by the big 3 compilers?

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EDIT: Now with a Godbolt minimal example https://godbolt.org/z/hvbb6jv9W

Answer 1

Use template instead of typename. And, note that while typename would go before the ::, template goes after.

template<class T_other>
void bar() {
    instance.foo<T_other::template template_type>();
}

Complete example.