JavaScript Array every

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

Syntax

array.every(callback [, contextObject])

Parameters

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

Cross-browser Array every

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

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

        var thisp = arguments[1];
        for (var i = 0; i < len; i++) {
            if (i in this && !fun.call(thisp, this[i], i, this)) {
                return false;
            }
        }

        return true;
    };
}

See also

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