Name
Array.shift( ): shift array elements down â ECMAScript v3
Synopsis
array
.shift( )
Returns
The former first element of the array.
Description
shift( )
removes and
returns the first element of array
,
shifting all subsequent elements down one place to occupy the newly
vacant space at the start of the array. If the array is empty,
shift( )
does nothing and returns
the undefined
value. Note that
shift( )
does not create a new
array; instead, it modifies array
directly.
shift( )
is similar to
Array.pop( )
, except it operates
on the beginning of an array rather than the end. shift( )
is often used in conjunction with
unshift( )
.
Example
var a = [1, [2,3], 4] a.shift( ); // Returns 1; a = [[2,3], 4] a.shift( ); // Returns [2,3]; a = [4]
See Also
Array.pop( ), Array.unshift( )
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