Namespaces
Variants
Views
Actions

std::negate

From cppreference.com
< cpp‎ | utility‎ | functional
Revision as of 16:48, 9 November 2013 by Cubbi (Talk | contribs)

(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
 
 
 
Function objects
Function wrappers
(C++11)
(C++11)
Bind
(C++11)
Reference wrappers
(C++11)(C++11)
Operator wrappers
Negators
Deprecated binders and adaptors
(until C++17)
(until C++17)
(until C++17)
(until C++17)
(until C++17)(until C++17)(until C++17)(until C++17)
(until C++17)
(until C++17)(until C++17)(until C++17)(until C++17)
(until C++17)(until C++17)
(until C++17)(until C++17)
 

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

Function object for performing negation. Effectively calls operator- on an instance of type T.

Contents

[edit] Specializations

The standard library provides a specialization of std::negate when T is not specified, which leaves the parameter types and return type to be deduced.

function object implementing -x deducing argument and return types
(class template specialization) [edit]
(since C++14)

[edit] Member types

Type Definition
result_type T
argument_type T

[edit] Member functions

operator()
returns the negation of the argument
(public member function)

std::negate::operator()

T operator()( const T& arg ) const;
(until C++14)
constexpr T operator()( const T& arg ) const;
(since C++14)

Returns the negation of arg.

Parameters

arg - value to compute negation of

Return value

The result of -arg.

Exceptions

(none)

Possible implementation

constexpr T operator()(const T &arg) const 
{
    return -arg;
}