std::meta::is_structural_type

 

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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 bool is_structural_type( std::meta::info r );		(since C++26)

Returns true if r is a reflection of a structural type. Otherwise returns false.

Parameters

r

-

a reflection value

Exceptions

Throws std::meta::exception if r does not represent a type or type alias.

Return value

true if r represents a structural type; otherwise false.

Example

Run this code

#include <meta>

struct S { int x; };
class Bad1 { int x; };
struct Bad2 { mutable int x; };
struct A { int a[2][3]; };
struct B : public S {}; // OK: public base of structural type
struct C : private S {}; // not structural: private base
auto L = [](int n){ return 2 * n; }; // captureless lambda

static_assert( std::meta::is_structural_type(^^int));   // scalar 
static_assert( std::meta::is_structural_type(^^int&));  // lvalue ref
static_assert(!std::meta::is_structural_type(^^int&&)); // rvalue ref is not structural

static_assert( std::meta::is_structural_type(^^S));
static_assert(!std::meta::is_structural_type(^^Bad1));
static_assert(!std::meta::is_structural_type(^^Bad2));
static_assert( std::meta::is_structural_type(^^A));
static_assert( std::meta::is_structural_type(^^B));
static_assert(!std::meta::is_structural_type(^^C));
static_assert( std::meta::is_structural_type(^^decltype(L)));

int main() {}

See also

is_structural (C++26)

checks if a type is a structural type (class template)