JavaScript Array some

The JavaScript Array some method checks whether some elements of an array pass the test implemented by the callback function.


array.some(callback [, contextObject])


The callback function to test each element
Object to be used as a context for the callback function

Cross-browser Array some

For browsers that don't support the Array some method, here's an alternative implementation:

 * Copyright (c) Mozilla Foundation
 * This code is available under the terms of the MIT License
if (!Array.prototype.some) {
    Array.prototype.some = function(fun /*, thisp*/) {
        var i = 0, len = this.length >>> 0;
        if (typeof fun != "function") {
            throw new TypeError();

        var thisp = arguments[1];
        for (; i < len; i++) {
            if (i in this &&, this[i], i, this)) {
                return true;

        return false;

See also

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