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    shift

    Summary

    The shift() method removes the first element from an array and returns that element. This method changes the length of the array.

    Syntax

    arr.shift()

    Description

    The shift method removes the element at the zeroeth index and shifts the values at consecutive indexes down, then returns the removed value. If the length property is 0, undefined is returned.

    shift is intentionally generic; this method can be called or applied to objects resembling arrays. Objects which do not contain a length property reflecting the last in a series of consecutive, zero-based numerical properties may not behave in any meaningful manner.

    Examples

    Example: Removing an element from an array

    The following code displays the myFish array before and after removing its first element. It also displays the removed element:

    var myFish = ["angel", "clown", "mandarin", "surgeon"];
    
    console.log("myFish before: " + myFish);
    
    var shifted = myFish.shift();
    
    console.log("myFish after: " + myFish);
    console.log("Removed this element: " + shifted);
    

    This example displays the following:

    myFish before: angel,clown,mandarin,surgeon
    myFish after: clown,mandarin,surgeon
    Removed this element: angel
    

    Specifications

    Specification Status Comment
    ECMAScript 3rd Edition Standard Initial definition. Implemented in JavaScript 1.2
    ECMAScript Language Specification 5.1th Edition (ECMA-262) Standard  
    ECMAScript Language Specification 6th Edition (ECMA-262) Draft  

    Browser compatibility

    Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
    Basic support 1.0 1.0 (1.7 or earlier) 5.5 (Yes) (Yes)
    Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
    Basic support (Yes) (Yes) (Yes) (Yes) (Yes) (Yes)

    See also

    Document Tags and Contributors

    Contributors to this page: Vinícius Albuquerque
    Last updated by: Vinícius Albuquerque,
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