std::meta::members_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

Primary type categories is_void_type is_null_pointer_type is_integral_type is_floating_point_type is_array_type is_pointer_type is_lvalue_reference_type is_rvalue_reference_type is_member_object_pointer_type is_member_function_pointer_type      is_enum_type is_union_type is_class_type is_function_type is_reflection_type Composite type categories is_reference_type is_arithmetic_type is_fundamental_type is_object_type is_scalar_type is_compound_type is_member_pointer_type Type properties ➜ Type relations is_same_type is_base_of_type is_virtual_base_of_type is_convertible_type is_nothrow_convertible_type is_layout_compatible_type is_pointer_interconvertible_   base_of_type is_invocable_type is_invocable_r_type is_nothrow_invocable_type is_nothrow_invocable_r_type

Const-volatile modifications remove_const remove_volatile remove_cv add_const add_volatile add_cv Reference modifications remove_reference add_lvalue_reference add_rvalue_reference Sign modifications make_signed make_unsigned Array modifications remove_extent remove_all_extents Pointer modifications remove_pointer add_pointer Other transformations remove_cvref decay common_type common_reference underlying_type invoke_result unwrap_reference unwrap_ref_decay

 

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Reflection queries type_of object_of constant_of is_public is_protected is_private is_virtual is_pure_virtual is_override is_final is_deleted is_defaulted is_user_provided is_user_declared is_explicit is_noexcept is_bit_field is_enumerator is_annotation is_const is_volatile is_mutable_member is_lvalue_reference_qualified is_rvalue_reference_qualified has_static_storage_duration has_thread_storage_duration has_automatic_storage_duration      has_internal_linkage has_module_linkage has_external_linkage has_c_language_linkage has_linkage is_complete_type is_enumerable_type is_variable is_type is_namespace is_type_alias is_namespace_alias is_function is_conversion_function is_operator_function is_literal_operator is_special_member_function is_constructor is_default_constructor is_copy_constructor

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is_standard_layout_type is_empty_type is_polymorphic_type is_abstract_type is_final_type is_aggregate_type is_structural_type is_signed_type is_unsigned_type is_bounded_array_type is_unbounded_array_type is_scoped_enum_type is_constructible_type is_default_constructible_type is_copy_constructible_type is_move_constructible_type is_assignable_type is_copy_assignable_type is_move_assignable_type is_swappable_with_type is_swappable_type is_destructible_type is_trivially_constructible_type is_trivially_default_constructible_type is_trivially_copy_constructible_type is_trivially_move_constructible_type is_trivially_assignable_type is_trivially_copy_assignable_type is_trivially_move_assignable_type is_trivially_destructible_type is_nothrow_constructible_type is_nothrow_default_constructible_type is_nothrow_copy_constructible_type is_nothrow_move_constructible_type is_nothrow_assignable_type is_nothrow_copy_assignable_type is_nothrow_move_assignable_type is_nothrow_swappable_with_type is_nothrow_swappable_type is_nothrow_destructible_type is_implicit_lifetime_type has_virtual_destructor has_unique_object_representations reference_constructs_from_temporary reference_converts_from_temporary Type property queries rank extent

 

Defined in header <meta>
consteval std::vector<std::meta::info> members_of( std::meta::info r, std::meta::access_context ctx );		(since C++26)

Returns a std::vector containing the reflections of the members of the class type or namespace represented by r, filtered by the access context ctx.

Each reflection m in the result represents an accessible member that has an eligible declaration and is representable (see below). Accessibility is determined as if by std::meta::is_accessible(m, ctx).

Let Q be the class type or namespace represented by r.

A declaration is eligible if it meets all the following requirements:

• It is in the scope of Q. (A block-scope function declaration is not eligible, for example.)
• It is not a friend declaration.
• It is not the declaration of a closure type.
• It is not the declaration of a (partial or full) template specialization.
• If Q is a class type that is not a closure type, the declaration introduces a direct member of Q that is not a variant member of a nested anonymous union of Q.
• If Q is a closure type, the declaration introduces a function call operator or function call operator template.

It is implementation-defined whether declarations of other members of a closure type Q are eligible.

Only declarations before the members_of call are considered.

A member is representable if it is one of the following:

• a class or enumeration type
• a type alias
• a class template, function template, variable template, alias template, or concept
• a variable or reference whose type does not contain an undeduced placeholder type
• a function F for which:

• the type of F does not contain an undeduced placeholder type;
• the constraints (if any) of F are satisfied; and
• if F is a prospective destructor, it is the selected destructor

• a data member
• a namespace
• a namespace alias

This function treats unnamed bit-fields declared in the scope of Q as data members with the same access.

Reflections of class members and unnamed bit-fields appear in the order in which they are declared. Implicitly-declared special members appear after any user-defined members.

Parameters

r	-	a reflection of complete class type or namespace
ctx	-	an access context

Return value

A std::vector of reflection values that represents class members or namespace members.

Exceptions

Throws std::meta::exception unless std::meta::dealias(r) represents either a class type complete from some point in the evaluation context, or a namespace.

See also

bases_of (C++26)

obtains the accessible direct bases of the reflected class (function)