std::array<T,N>::front

 

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std::array

Member types
Member functions
Element access array::at array::operator[]    array::front array::back array::data Operations array::fill array::swap	Iterators array::beginarray::cbegin array::endarray::cend array::rbeginarray::crbegin    array::rendarray::crend	Capacity array::empty array::size array::max_size
Non-member functions
operator==operator<=> (C++20) get(std::array) swap(std::array) to_array (C++20)	operator|=operator<operator>operator<=operator>= (until C++20)(until C++20)(until C++20)(until C++20)(until C++20)
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tuple_element<std::array>
Deduction guides (C++17)

 

reference front();	(1)	(since C++11) (constexpr since C++17)
const_reference front() const;	(2)	(since C++11) (constexpr since C++14)

Returns a reference to the first element in the container.

Calling front on an empty container causes undefined behavior.

Parameters

(none)

Return value

Reference to the first element.

Complexity

Constant.

Notes

For a container c, the expression c.front() is equivalent to *c.begin().

Example

The following code uses front to display the first element of a std::array<char, 4>:

Run this code

#include <cassert>
#include <array>
 
int main()
{
    std::array<char, 4> letters{'a', 'b', 'c', 'd'};
    assert(letters.front() == 'a');
}

See also

back	access the last element (public member function)
rendcrend	returns a reverse iterator to the end (public member function)
begincbegin	returns an iterator to the beginning (public member function)
data	direct access to the underlying contiguous storage (public member function)