templatetypename

Templatetypename is not an official keyword in major programming languages. It is a descriptive phrase sometimes used to refer to the interaction between the template and typename keywords in C++ templates. The concept describes how templates are declared with template parameters and how types within those templates are identified and disambiguated.

In C++, templates enable generic programming by parameterizing code with types or values. A typical template declaration uses template and a parameter list, such as template <typename T> or template <class T>. The two forms are functionally equivalent for declaring a type parameter, though the choice of keyword can reflect stylistic preference. The typename keyword also appears inside templates to declare that a dependent name represents a type, which is essential for correct compilation in many generic contexts. For example, within a template<class T> void f() { typename T::value_type v; } the typename indicates that value_type is a type name dependent on T.

Advanced usage often involves the need to disambiguate names when calling member templates on dependent objects, using the syntax obj.template method<Args>(args). This interplay of template and typename features—how type names are declared and how dependent names are interpreted—underpins much of template programming in C++ and is sometimes summarized in informal discussions as templatetypename.

In practice, templatetypename is a conceptual shorthand rather than a literal keyword. Programmers should rely on the official keywords template, typename, and, where needed, the template disambiguator, to read and write correct template code. See also C++ templates, typename, template (C++).