std::plus

 

C++

Language

Standard Library Headers

Freestanding and hosted implementations

Named requirements

Language support library

Concepts library (C++20)

Diagnostics library

Utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Localizations library

Input/output library

Filesystem library (C++17)

Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

Technical Specifications

 

Utilities library

Language support Type support (basic types, RTTI, type traits)      Library feature-test macros (C++20) Dynamic memory management Program utilities Error handling Coroutine support (C++20) Variadic functions launder (C++17) initializer_list (C++11) source_location (C++20) Three-way comparison (C++20) 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) compare_three_way (C++20) strong_order (C++20) weak_order (C++20) partial_order (C++20) compare_strong_order_fallback (C++20) compare_weak_order_fallback (C++20) compare_partial_order_fallback (C++20) is_eqis_neqis_ltis_lteqis_gtis_gteq (C++20)(C++20)(C++20)(C++20)(C++20)(C++20)

General utilities Date and time Function objects bitset Formatting library (C++20) hash (C++11) integer_sequence (C++14) 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) forward (C++11) move (C++11) move_if_noexcept (C++11) as_const (C++17) to_underlying (C++23) 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) Elementary string conversions to_chars (C++17) from_chars (C++17) chars_format (C++17) Stacktrace stacktrace_entry (C++23) basic_stacktrace (C++23)

 

Function objects

Function wrappers function (C++11) mem_fn (C++11) bad_function_call (C++11)	Partial function application bind_front (C++20) bind (C++11) is_bind_expression (C++11) is_placeholder (C++11) _1, _2, _3, ... (C++11)
Function invocation invoke (C++17) Identity function object identity (C++20)	Reference wrappers reference_wrapper (C++11) refcref (C++11)(C++11) unwrap_referenceunwrap_ref_decay (C++20)(C++20)
Operator wrappers
plus minus negate multiplies divides modulus logical_and logical_or logical_not equal_to	not_equal_to greater less greater_equal less_equal bit_and bit_or bit_xor bit_not (C++14)
Negators not_fn (C++17) Searchers default_searcher (C++17) boyer_moore_searcher (C++17) boyer_moore_horspool_searcher (C++17)	Constrained comparators ranges::equal_to (C++20) ranges::not_equal_to (C++20) ranges::greater (C++20) ranges::less (C++20) ranges::greater_equal (C++20) ranges::less_equal (C++20) compare_three_way (C++20)
Old binders and adaptors
unary_function (until C++17) binary_function (until C++17) ptr_fun (until C++17) pointer_to_unary_function (until C++17) pointer_to_binary_function (until C++17) mem_fun (until C++17) mem_fun_tmem_fun1_tconst_mem_fun_tconst_mem_fun1_t (until C++17)(until C++17)(until C++17)(until C++17) not1 (until C++20) not2 (until C++20)	binder1stbinder2nd (until C++17)(until C++17) bind1stbind2nd (until C++17)(until C++17) mem_fun_ref (until C++17) mem_fun_ref_tmem_fun1_ref_tconst_mem_fun_ref_tconst_mem_fun1_ref_t (until C++17)(until C++17)(until C++17)(until C++17) unary_negate (until C++20) binary_negate (until C++20)

 

Defined in header <functional>
template< class T > struct plus;		(until C++14)
template< class T = void > struct plus;		(since C++14)

Function object for performing addition. Effectively calls operator+ on two instances of type T.

Specializations

The standard library provides a specialization of std::plus when T is not specified, which leaves the parameter types and return type to be deduced. plus<void> (C++14) function object implementing x + y deducing argument and return types (class template specialization)

(since C++14)

Member types Type Definition result_type (deprecated in C++17) T first_argument_type (deprecated in C++17) T second_argument_type (deprecated in C++17) T

(until C++20)

Member functions

operator()

returns the sum of two arguments (public member function)

std::plus::operator()

T operator()( const T& lhs, const T& rhs ) const;		(until C++14)
constexpr T operator()( const T& lhs, const T& rhs ) const;		(since C++14)

Returns the sum of lhs and rhs.

Parameters

lhs, rhs

-

values to sum

Return value

The result of lhs + rhs.

Exceptions

May throw implementation-defined exceptions.

Possible implementation

constexpr T operator()(const T &lhs, const T &rhs) const { return lhs + rhs; }