Name
Array.shift() — shift array elements down
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
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