std::initializer_list

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Defined in header `<initializer_list>`

template< class T > class initializer_list;		(since C++11)

An object of type std::initializer_list<T> is passed, by value, to the constructors of objects when they are initialized using initializer list syntax. It is a thin wrapper around an array of objects of type T, typically implemented as a pair of pointers or pointer and length. Copying a std::initializer_list does not copy the underlying objects.

#include <iostream>
#include <vector>
#include <initializer_list>
 
template<class T>
struct S {
    std::vector<T> v;
    S(std::initializer_list<T> l) : v(l) {
         std::cout << "constructed with a " << l.size() << "-element list\n";
    }
};
 
int main()
{
    S<int> s = {1,2,3,4,5};
    std::cout << "The vector now holds ";
    for(auto n : s.v) std::cout << n << ' ';
    std::cout << '\n';
}

Output:

constructed with a 5 element list
The vector now holds 1 2 3 4 5


Member type	Definition

`value_type`	T

`reference`	const T&

`const_reference`	const T&

`size_type`	size_t

`iterator`	const T*

`const_iterator`	const T*


(constructor)	constructs the initializer list (public member function)
Capacity

size	returns the size of the initializer list (public member function)
Iterators

begin	returns a pointer to the first element (public member function)

end	returns a pointer one past the last element (public member function)


std::begin(std::initializer_list) (C++11)	specializes std::begin (function template)

std::end(std::initializer_list) (C++11)	specializes std::end (function template)

std::initializer_list

From Cppreference

Contents

[edit] Member types

[edit] Member functions

Capacity

Iterators

[edit] Non-member functions

[edit] Example