std::meta::has_default_member_initializer

 

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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 Reflection layout queries offset_of size_of alignment_of bit_size_of Annotation reflection annotations_of annotations_of_with_type Value extraction extract Reflection substitution can_substitute substitute Expression result reflection reflect_constant reflect_object reflect_function Class definition generation data_member_spec is_data_member_spec define_aggregate

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Defined in header <meta>
consteval bool has_default_member_initializer( std::meta::info r );		(since C++26)

Returns true if r represents a non-static data member that has a default member initializer. Otherwise returns false.

Parameters

r

-

a reflection value

Return value

true if r has a default member initializer; otherwise false.

Example

Run this code

#include <meta>

struct S
{
    int a;
    double b{0.0};
};

static_assert(!has_default_member_initializer(^^S::a));
static_assert(has_default_member_initializer(^^S::b));

int main() {}

See also

is_nonstatic_data_member (C++26)

checks if reflection represents a non-static data member (function)