std::hash<std::type_index> - cppreference.com

Compiler support
Freestanding and hosted
Language
Standard library
Standard library headers
Named requirements
Feature test macros (C++20)
Language support library
Concepts library (C++20)
Diagnostics library
Memory management library
Metaprogramming library (C++11)
General utilities library
Containers library
Iterators library
Ranges library (C++20)
Algorithms library
Strings library
Text processing library
Numerics library
Date and time library
Input/output library
Filesystem library (C++17)
Concurrency support library (C++11)
Execution control library (C++26)
Technical specifications
Symbols index
External libraries

[edit]

Utilities library

Language support

Type support (basic types, RTTI)

Library feature-test macros (C++20)

Program utilities

Variadic functions

initializer_list

(C++11)

is_constant_evaluated

(C++20)

is_within_lifetime

(C++26)

source_location

(C++20)

Coroutine support (C++20)

Contract support (C++26)

Three-way comparison

three_way_comparablethree_way_comparable_with

(C++20)(C++20)

strong_ordering

(C++20)

weak_ordering

(C++20)

partial_ordering

(C++20)

common_comparison_category

(C++20)

compare_three_way_result

(C++20)

(C++20)

(C++20)

(C++20)

(C++20)

compare_strong_order_fallback

(C++20)

compare_weak_order_fallback

(C++20)

compare_partial_order_fallback

(C++20)

is_eqis_ltis_lteq

(C++20)(C++20)(C++20)

is_neqis_gtis_gteq

(C++20)(C++20)(C++20)

General utilities

Function objects
Bit manipulation (C++20)
bitset
hash (C++11)

Relational operators (deprecated in C++20)

rel_ops::operator!=rel_ops::operator>

rel_ops::operator<=rel_ops::operator>=

Integer comparison functions

cmp_equalcmp_lesscmp_less_than

(C++20)(C++20)(C++20)

cmp_not_equalcmp_greatercmp_greater_than

(C++20)(C++20)(C++20)

in_range

(C++20)

Swap and type operations

swap
ranges::swap (C++20)
exchange (C++14)
declval (C++11)
to_underlying (C++23)

forward (C++11)
forward_like (C++23)
move (C++11)
move_if_noexcept (C++11)
as_const (C++17)

Common vocabulary types

pair
tuple (C++11)
optional (C++17)
any (C++17)
variant (C++17)

tuple_size (C++11)
tuple_element (C++11)
apply (C++17)
make_from_tuple (C++17)
expected (C++23)

[edit]

Type support

Basic types

Fixed width integer types (C++11)

Fixed width floating-point types (C++23)

ptrdiff_t
size_t
max_align_t (C++11)
byte (C++17)

nullptr_t (C++11)
offsetof
NULL

Numeric limits

numeric_limits

C numeric limits interface

Runtime type information

type_info
type_index (C++11)

bad_typeid
bad_cast

[edit]

std::type_index

Member functions
type_index::type_index
type_index::operator=type_index::operator!=type_index::operator<type_index::operator<=type_index::operator>type_index::operator>=type_index::operator<=> (until C++20)(C++20)
type_index::hash_code
type_index::name
Helper classes
hash<std::type_index> (C++11)

[edit]

Defined in header `<typeindex>`
`template<> struct hash<std::type_index>;`		(since C++11)

The template specialization of std::hash for std::type_index allows users to obtain hashes of objects of type std::type_index.

The member operator() effectively returns the same value as hash_code().

See also