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c++ - What are qualified-id/name and unqualified-id/name?

I was wondering if someone could explain there terms since I encounter them in many places. I know some basic theory about them but not sure what I know is right or wrong.

So can any one please explain these terms?

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A qualified name is one that has some sort of indication of where it belongs, e.g. a class specification, namespace specification, etc. An unqualified name is one that isn't qualified.

Read James McNellis' answer here:

What is a nested name specifier?

Given:

struct  A {
    struct B {
        void F();
    };
};
  • A is an unqualified-id.
  • ::A is a qualified-id but has no nested-name-specifier.
  • A::B is a qualified-id and A:: is a nested-name-specifier.
  • ::A::B is a qualified-id and A:: is a nested-name-specifier.
  • A::B::F is a qualified-id and both B:: and A::B:: are nested-name-specifiers.
  • ::A::B::F is a qualified-id and both B:: and A::B:: are nested-name-specifiers.


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