Member predicate Declaration::getTemplateArgument

Gets the ith template argument used to instantiate this declaration from a template.

For example:

template<typename T, T X> class Foo;

Will have getTemplateArgument(0) return T, and getTemplateArgument(1) return X.

Foo<int, 1> bar;

Will have getTemplateArgument()) return int, and getTemplateArgument(1) return 1.