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    Revision as of 22:51, 6 June 2011

     
    C++
     
    Containers library
     
    std::array
     
    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.

    If empty() is true, the behavior is undefined.

    		(until C++26)

    If empty() is true:

    		(since C++26)

    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

    		 access the last element
    (public member function) [edit]
    		returns a reverse iterator to the end
    (public member function) [edit]
    		returns an iterator to the beginning
    (public member function) [edit]
    		direct access to the underlying contiguous storage
    (public member function) [edit]