JavaScript: The Definitive Guide, Fourth Edition

Name

Array.pop( ) — remove and return the last element of an array

Availability

JavaScript 1.2; JScript 5.5; ECMAScript v3

Synopsis

                  array.pop( )

Returns

The last element of array.

Description

pop( ) deletes the last element of array, decrements the array length, and returns the value of the element that it deleted. If the array is already empty, pop( ) does not change the array and returns the undefined value.

Example

pop( ), and its companion method push( ), provide the functionality of a first-in, last-out stack. For example:

var stack = [];       // stack: []
stack.push(1, 2);     // stack: [1,2]     Returns 2
stack.pop(  );        // stack: [1]       Returns 2
stack.push([4,5]);    // stack: [1,[4,5]] Returns 2
stack.pop(  )         // stack: [1]       Returns [4,5]
stack.pop(  );        // stack: []        Returns 1

See Also

Array.push( )