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

 

C++

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std::array

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Element access

array::at

array::operator[]

array::front

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array::beginarray::cbegin

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operator==operator!=operator<operator>operator<=operator>=operator<=> (until C++20)(until C++20)(until C++20)(until C++20)(until C++20)(C++20)

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Deduction guides(C++17)

 

reference front();		(until C++17)
constexpr reference front();		(since C++17)
const_reference front() const;		(until C++14)
constexpr const_reference front() const;		(since C++14)

Returns a reference to the first element in the container.

Calling front on an empty container is undefined.

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, 6>:

Run this code

#include <array>
#include <iostream>
 
int main()
{
    std::array<char, 6> letters {'o', 'm', 'g', 'w', 't', 'f'};
 
    if (!letters.empty()) {
        std::cout << "The first character is '" << letters.front() << "'.\n";
    }  
}

Output:

The first character is 'o'.

See also

back (C++11)

access the last element (public member function)