std::meta::is_lvalue_reference_type

 

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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 tuple_size tuple_element is_applicable_type is_nothrow_applicable_type apply_result variant_size variant_alternative type_order

 

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

Returns true if r represents an lvalue reference. Otherwise returns false.

Parameters

r

-

a reflection value

Return value

true if r represents an lvalue reference; otherwise false.

Exceptions

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

Example

Run this code

#include <meta>

static_assert(is_lvalue_reference_type(^^int) == false);
static_assert(is_lvalue_reference_type(^^int&) == true);
static_assert(is_lvalue_reference_type(^^int&&) == false);
static_assert(is_rvalue_reference_type(^^int&&) == true);

class A {};
static_assert(is_lvalue_reference_type(^^A) == false);
static_assert(is_lvalue_reference_type(^^A&) == true);
static_assert(is_lvalue_reference_type(^^A&&) == false);
static_assert(is_rvalue_reference_type(^^A&&) == true);

int main() {}

See also

is_rvalue_reference_type (C++26)	checks if reflection represents an rvalue reference (function)
is_reference_type (C++26)	checks if reflection represents either an lvalue reference or rvalue reference (function)
is_lvalue_reference (C++11)	checks if a type is an lvalue reference (class template)