getuserbarcode/src/common/typedefs.js

An advanced barcode-scanner written in JavaScript

/*
 * typedefs.js
 * Normalizes browser-specific prefixes
 */

if (typeof window !== 'undefined') {
    window.requestAnimFrame = (function () {
        return window.requestAnimationFrame ||
            window.webkitRequestAnimationFrame ||
            window.mozRequestAnimationFrame ||
            window.oRequestAnimationFrame ||
            window.msRequestAnimationFrame ||
            function (/* function FrameRequestCallback */ callback) {
                window.setTimeout(callback, 1000 / 60);
            };
    })();
}
Math.imul = Math.imul || function(a, b) {
    var ah = (a >>> 16) & 0xffff,
        al = a & 0xffff,
        bh = (b >>> 16) & 0xffff,
        bl = b & 0xffff;
    // the shift by 0 fixes the sign on the high part
    // the final |0 converts the unsigned value into a signed value
    return ((al * bl) + (((ah * bl + al * bh) << 16) >>> 0) | 0);
};

if (typeof Object.assign !== 'function') {
    Object.assign = function(target) { // .length of function is 2
        'use strict';
        if (target === null) { // TypeError if undefined or null
            throw new TypeError('Cannot convert undefined or null to object');
        }

        var to = Object(target);

        for (var index = 1; index < arguments.length; index++) {
            var nextSource = arguments[index];

            if (nextSource !== null) { // Skip over if undefined or null
                for (var nextKey in nextSource) {
                    // Avoid bugs when hasOwnProperty is shadowed
                    if (Object.prototype.hasOwnProperty.call(nextSource, nextKey)) {
                        to[nextKey] = nextSource[nextKey];
                    }
                }
            }
        }
        return to;
    };
}