std::incrementable_traits

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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)
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Iterator library

Iterator concepts

indirectly_readable (C++20)
indirectly_writable (C++20)
weakly_incrementable (C++20)
incrementable (C++20)
is-integer-like is-signed-integer-like (C++20)(C++20)

sentinel_for (C++20)
sized_sentinel_for (C++20)
input_iterator (C++20)
output_iterator (C++20)
input_or_output_iterator (C++20)

forward_iterator (C++20)
bidirectional_iterator (C++20)
random_access_iterator (C++20)
contiguous_iterator (C++20)

Iterator primitives

input_iterator_tagoutput_iterator_tagforward_iterator_tagbidirectional_iterator_tagrandom_access_iterator_tagcontiguous_iterator_tag

(C++20)

iter_value_titer_difference_titer_reference_titer_const_reference_titer_rvalue_reference_titer_common_reference_t

(C++20)(C++20)(C++20)(C++23)(C++20)(C++20)

iterator (deprecated in C++17)
iterator_traits
incrementable_traits (C++20)
indirectly_readable_traits (C++20)

Algorithm concepts and utilities

Indirect callable concepts

indirectly_unary_invocableindirectly_regular_unary_invocable

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

indirect_unary_predicate (C++20)
indirect_binary_predicate (C++20)

indirect_equivalence_relation (C++20)
indirect_strict_weak_order (C++20)

Common algorithm requirements

indirectly_movable (C++20)
indirectly_movable_storable (C++20)
indirectly_copyable (C++20)

indirectly_copyable_storable (C++20)
indirectly_swappable (C++20)
indirectly_comparable (C++20)

permutable (C++20)
mergeable (C++20)
sortable (C++20)

(C++20)

(C++20)

(C++26)

reverse_iterator
make_reverse_iterator (C++14)
move_iterator (C++11)
make_move_iterator (C++11)
default_sentinel_tdefault_sentinel (C++20)(C++20)
unreachable_sentinel_tunreachable_sentinel (C++20)(C++20)

front_insert_iterator
back_insert_iterator
inserter
insert_iterator
front_inserter
back_inserter
move_sentinel (C++20)

common_iterator (C++20)
counted_iterator (C++20)
basic_const_iterator (C++23)
const_iterator (C++23)
const_sentinel (C++23)
make_const_iterator (C++23)
make_const_sentinel (C++23)

Stream iterators

istream_iterator
ostream_iterator

istreambuf_iterator
ostreambuf_iterator

Iterator customization points
ranges::iter_move (C++20)
ranges::iter_swap (C++20)

Iterator operations

advance
distance
prev (C++11)
next (C++11)

ranges::advance (C++20)
ranges::distance (C++20)
ranges::prev (C++20)
ranges::next (C++20)

Range access

begincbegin (C++11)(C++14)
rbegincrbegin (C++14)(C++14)

endcend (C++11)(C++14)
rendcrend (C++14)(C++14)

sizessize (C++17)(C++20)
empty (C++17)
data (C++17)

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Defined in header`<iterator>`
template<class I> struct incrementable_traits{};	(1)	(since C++20)
template<class T> requiresstd::is_object_v<T> struct incrementable_traits<T*>;	(2)	(since C++20)
template<class T> struct incrementable_traits<const T> : incrementable_traits<T>{};	(3)	(since C++20)
template<class T> requires requires{typename T::difference_type;} struct incrementable_traits<T>;	(4)	(since C++20)
template<class T> requires(!requires{typename T::difference_type;})&& requires(const T& a,const T& b){{ a- b}->std::integral;} struct incrementable_traits<T>;	(5)	(since C++20)

Computes the associated difference type of the typeI, if any. A program may specializeincrementable_traits for aprogram-defined type.

1) Primary template is an empty struct.

2) Specialization for pointers.

Provides a member typedifference_type same asstd::ptrdiff_t.

3) Specialization for const-qualified types.

4) Specialization for types that define a public and accessible member typedifference_type.

Provides a member typedifference_type same asT::difference_type.

5) Specialization for types that do not define a public and accessible member typedifference_type but do support subtraction.

Provides a member typedifference_type same asstd::make_signed_t<decltype(std::declval<T>()-std::declval<T>())>. The implicit expression variations rule (see below) applies to the expressiona- b.

[edit]Implicit expression variations

Arequires expression that uses an expression that is non-modifying for some constant lvalue operand also requiresimplicit expression variations.

[edit]Example

This section is incomplete
Reason: no example

[edit]See also

weakly_incrementable (C++20)	specifies that a`semiregular` type can be incremented with pre- and post-increment operators (concept)[edit]
iter_value_titer_reference_titer_const_reference_titer_difference_titer_rvalue_reference_titer_common_reference_t (C++20)(C++20)(C++23)(C++20)(C++20)(C++20)	computes the associated types of an iterator (alias template)[edit]
iterator_traits	provides uniform interface to the properties of an iterator (class template)[edit]