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    The some() method tests whether some element in the array passes the test implemented by the provided function.


    arr.some(callback[, thisArg])


    Function to test for each element, taking three arguments:
    The current element being processed in the array.
    The index of the current element being processed in the array.
    The array some() was called upon.
    Optional. Value to use as this when executing callback.


    some() executes the callback function once for each element present in the array until it finds one where callback returns a true value. If such an element is found, some() immediately returns true. Otherwise, some() returns false. callback is invoked only for indexes of the array which have assigned values; it is not invoked for indexes which have been deleted or which have never been assigned values.

    callback is invoked with three arguments: the value of the element, the index of the element, and the array object being traversed.

    If a thisArg parameter is provided to some(), it will be passed to callback when invoked, for use as its this value. Otherwise, the value undefined will be passed for use as its this value. The this value ultimately observable by callback is determined according to the usual rules for determining the this seen by a function.

    some() does not mutate the array on which it is called.

    The range of elements processed by some() is set before the first invocation of callback. Elements that are appended to the array after the call to some() begins will not be visited by callback. If an existing, unvisited element of the array is changed by callback, its value passed to the visiting callback will be the value at the time that some() visits that element's index; elements that are deleted are not visited.


    Example: Testing value of array elements

    The following example tests whether any element in the array is bigger than 10.

    function isBiggerThan10(element, index, array) {
      return element > 10;
    [2, 5, 8, 1, 4].some(isBiggerThan10);  // false
    [12, 5, 8, 1, 4].some(isBiggerThan10); // true

    Example: Testing array elements using arrow functions

    Arrow functions provide a shorter syntax for the same test.

    [2, 5, 8, 1, 4].some(elem => elem > 10);  // false
    [12, 5, 8, 1, 4].some(elem => elem > 10); // true


    some() was added to the ECMA-262 standard in the 5th edition; as such it may not be present in all implementations of the standard. You can work around this by inserting the following code at the beginning of your scripts, allowing use of some() in implementations which do not natively support it. This algorithm is exactly the one specified in ECMA-262, 5th edition, assuming Object and TypeError have their original values and that evaluates to the original value of

    // Production steps of ECMA-262, Edition 5,
    // Reference:
    if (!Array.prototype.some) {
      Array.prototype.some = function(fun/*, thisArg*/) {
        'use strict';
        if (this == null) {
          throw new TypeError('Array.prototype.some called on null or undefined');
        if (typeof fun !== 'function') {
          throw new TypeError();
        var t = Object(this);
        var len = t.length >>> 0;
        var thisArg = arguments.length >= 2 ? arguments[1] : void 0;
        for (var i = 0; i < len; i++) {
          if (i in t &&, t[i], i, t)) {
            return true;
        return false;


    Specification Status Comment
    ECMAScript 5.1 (ECMA-262)
    The definition of 'Array.prototype.some' in that specification.
    Standard Initial definition. Implemented in JavaScript 1.6.
    ECMAScript 6 (ECMA-262)
    The definition of 'Array.prototype.some' in that specification.
    Release Candidate  

    Browser compatibility

    Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
    Basic support (Yes) 1.5 (1.8) 9 (Yes) (Yes)
    Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
    Basic support (Yes) (Yes) 1.0 (1.8) (Yes) (Yes) (Yes)

    See also

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