std::remove_cvref

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Feature test macros(C++20)
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Containers library
Iterators library
Ranges library(C++20)
Algorithms library
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Date and time library
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Metaprogramming library

Type traits

Type categories

is_void

(C++11)

is_null_pointer

(C++11)(DR*)

is_array (C++11)
is_pointer (C++11)
is_enum (C++11)
is_union (C++11)
is_class (C++11)
is_function (C++11)
is_reference (C++11)

is_object (C++11)
is_scalar (C++11)
is_compound (C++11)
is_integral (C++11)
is_floating_point (C++11)
is_fundamental (C++11)
is_arithmetic (C++11)

is_lvalue_reference

(C++11)

is_rvalue_reference

(C++11)

is_member_pointer

(C++11)

is_member_object_pointer

(C++11)

is_member_function_pointer

(C++11)

Type properties

(C++11)

(C++11)

(C++11)

(C++11)

(C++14)

(C++11)

(C++17)

(C++23)

(C++11)(deprecated in C++26)

is_trivially_copyable

(C++11)

is_standard_layout

(C++11)

is_literal_type

(C++11)(until C++20*)

is_pod

(C++11)(deprecated in C++20)

(C++11)

(C++11)

(C++20)

(C++20)

(C++23)

has_unique_object_representations

(C++17)

Type trait constants

integral_constantbool_constanttrue_typefalse_type

(C++11)(C++17)(C++11)(C++11)

Metafunctions

conjunction

(C++17)

disjunction

(C++17)

negation

(C++17)

Supported operations

is_constructibleis_trivially_constructibleis_nothrow_constructible (C++11)(C++11)(C++11)
is_default_constructibleis_trivially_default_constructibleis_nothrow_default_constructible (C++11)(C++11)(C++11)
is_copy_constructibleis_trivially_copy_constructibleis_nothrow_copy_constructible (C++11)(C++11)(C++11)
is_move_constructibleis_trivially_move_constructibleis_nothrow_move_constructible (C++11)(C++11)(C++11)
is_assignableis_trivially_assignableis_nothrow_assignable (C++11)(C++11)(C++11)

is_copy_assignableis_trivially_copy_assignableis_nothrow_copy_assignable (C++11)(C++11)(C++11)
is_move_assignableis_trivially_move_assignableis_nothrow_move_assignable (C++11)(C++11)(C++11)
is_destructibleis_trivially_destructibleis_nothrow_destructible (C++11)(C++11)(C++11)
has_virtual_destructor (C++11)
is_swappable_withis_swappableis_nothrow_swappable_withis_nothrow_swappable (C++17)(C++17)(C++17)(C++17)

Relationships and property queries

is_same (C++11)
is_convertibleis_nothrow_convertible (C++11)(C++20)
is_layout_compatible (C++20)
is_pointer_interconvertible_base_of (C++20)
is_pointer_interconvertible_with_class (C++20)
is_corresponding_member (C++20)
reference_constructs_from_temporary (C++23)
reference_converts_from_temporary (C++23)

is_base_of (C++11)
is_virtual_base_of (C++26)
alignment_of (C++11)
rank (C++11)
extent (C++11)
is_invocableis_invocable_ris_nothrow_invocableis_nothrow_invocable_r (C++17)(C++17)(C++17)(C++17)

Type modifications

remove_cvremove_constremove_volatile (C++11)(C++11)(C++11)
add_cvadd_constadd_volatile (C++11)(C++11)(C++11)
make_signed (C++11)
make_unsigned (C++11)

remove_reference (C++11)
add_lvalue_referenceadd_rvalue_reference (C++11)(C++11)
remove_pointer (C++11)
add_pointer (C++11)
remove_extent (C++11)
remove_all_extents (C++11)

Type transformations

aligned_storage (C++11)(deprecated in C++23)
aligned_union (C++11)(deprecated in C++23)
decay (C++11)
remove_cvref (C++20)
result_ofinvoke_result (C++11)(until C++20*)(C++17)

conditional (C++11)
common_type (C++11)
common_reference (C++20)
underlying_type (C++11)
type_identity (C++20)
enable_if (C++11)
void_t (C++17)

Compile-time rational arithmetic

Compile-time integer sequences

integer_sequence

(C++14)

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Defined in header`<type_traits>`
template<class T> struct remove_cvref;		(since C++20)

If the typeT is a reference type, provides the member typedeftype which is the type referred to byT with its topmost cv-qualifiers removed. Otherwisetype isT with its topmost cv-qualifiers removed.

If the program adds specializations forstd::remove_cvref, the behavior is undefined.

[edit]Member types

Name	Definition
`type`	the type referred by`T` or`T` itself if it is not a reference, with top-level cv-qualifiers removed

[edit]Helper types

template<class T> using remove_cvref_t= remove_cvref<T>::type;		(since C++20)

[edit]Possible implementation

template<class T>struct remove_cvref{using type=std::remove_cv_t<std::remove_reference_t<T>>;};

[edit]Notes

Feature-test macro	Value	Std	Feature
`__cpp_lib_remove_cvref`	`201711L`	(C++20)	`std::remove_cvref`

[edit]Example

Run this code

#include <type_traits> int main(){    static_assert(std::is_same_v<std::remove_cvref_t<int>,int>);    static_assert(std::is_same_v<std::remove_cvref_t<int&>,int>);    static_assert(std::is_same_v<std::remove_cvref_t<int&&>,int>);    static_assert(std::is_same_v<std::remove_cvref_t<constint&>,int>);    static_assert(std::is_same_v<std::remove_cvref_t<constint[2]>,int[2]>);    static_assert(std::is_same_v<std::remove_cvref_t<constint(&)[2]>,int[2]>);    static_assert(std::is_same_v<std::remove_cvref_t<int(int)>,int(int)>);}

[edit]See also

remove_cvremove_constremove_volatile (C++11)(C++11)(C++11)	removesconst and/orvolatile specifiers from the given type (class template)[edit]
remove_reference (C++11)	removes a reference from the given type (class template)[edit]
decay (C++11)	applies type transformations as when passing a function argument by value (class template)[edit]