std::plus

 

C++

Language

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Utilities library

Strings library

Containers library

Algorithms library

Iterators library

Numerics library

Input/output library

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Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

Technical Specifications

 

Utilities library

Type support (basic types, RTTI, type traits)

Dynamic memory management

Error handling

Program utilities

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Date and time

Function objects

initializer_list (C++11)

bitset

hash (C++11)

Relational operators

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

Pairs and tuples

pair

tuple (C++11)

piecewise_construct_t (C++11)

piecewise_construct (C++11)

integer_sequence (C++14)

Swap, forward and move

swap

exchange (C++14)

forward (C++11)

move (C++11)

move_if_noexcept (C++11)

Type operations

declval (C++11)

as_const (C++17)

 

Function objects

Function wrappers
function (C++11)
mem_fn (C++11)
bad_function_call (C++11)
invoke (C++17)
Bind
bind (C++11)
is_bind_expression (C++11)
is_placeholder (C++11)
_1, _2, _3, ... (C++11)
Reference wrappers
reference_wrapper (C++11)
refcref (C++11)(C++11)
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
unary_negate binary_negate	not1 not2
Deprecated 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)
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)
binder1stbinder2nd (until C++17)(until C++17)
bind1stbind2nd (until C++17)(until C++17)

 

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> function object implementing x + y deducing argument and return types (class template specialization)

(since C++14)

Member types

Type	Definition
result_type	T
first_argument_type	T
second_argument_type	T

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

(none)

Possible implementation

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