std::meta::identifier_of, std::meta::u8identifier_of

 

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Member accessibility queries is_accessible has_inaccessible_nonstatic_   data_members has_inaccessible_bases has_inaccessible_subobjects      Scope identification current_function current_class current_namespace Reflection member queries members_of bases_of static_data_members_of nonstatic_data_members_of subobjects_of enumerators_of Annotation reflection annotations_of annotations_of_with_type Value extraction extract Reflection substitution reflection_range can_substitute substitute Expression result reflection reflect_constant reflect_object reflect_function Class definition generation data_member_options data_member_spec is_data_member_spec define_aggregate

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Defined in header <meta>
consteval std::string_view identifier_of( std::meta::info r );	(1)	(since C++26)
consteval std::u8string_view u8identifier_of( std::meta::info r );	(2)	(since C++26)

Returns the identifier associated with what r represents.

1) The result is a character string encoded in the ordinary literal encoding.

2) The result is a UTF-8 string.

The result string is determined as follows:

• If r represents an entity with a typedef name for linkage purposes, returns that name.
• Otherwise, if r represents a literal operator or literal operator template, returns its literal suffix identifier.
• Otherwise, if r represents a function parameter P of a function F, then let S be the set of declarations, ignoring any explicit instantiations, that are reachable from a point in the evaluation context and that declare either F or a templated function of which F is a specialization, returns the name that was introduced by a declaration in S for the parameter corresponding to P.
• Otherwise, if r represents an entity, returns its declared name.
• Otherwise, if r represents a direct base class relationship, returns std::meta::identifier_of(std::meta::type_of(r)) or std::meta::u8identifier_of(std::meta::type_of(r)).
• Otherwise, if r represents a data member description (T, N, A, W, NUA, ANN), returns the description's name N.

Parameters

r

-

a reflection value

Return value

The identifier of what r represents, as described above.

Exceptions

Throws std::meta::exception unless std::meta::has_identifier(r) is true and the result string is representable in the corresponding encoding.

Notes

The result V is null-terminated: V.data()[V.size()] is guaranteed to be '\0'. Each element in V is a potentially non-unique object with static storage duration that is usable in constant expressions; a pointer to such an element is not suitable for use as a template argument for a non-type template parameter of pointer type.

See also

has_identifier (C++26)

checks if reflection represents an entity that has an identifier (function)