use web worker inline wrapper.js

var wrapworker = function (_function, data) {
    var wrapr = this;var wrapworker = function (_function, data) {
    var wrapr = this;
    var mtd = "self.onmessage = function() {postMessage(" + _function.toString().replace('(','du(') + "(" + JSON.stringify(data) + "));};";
    blob = new Blob([mtd], { type: 'application/javascript' });
    var work = new Worker(URL.createObjectURL(blob));
    wrapr.ready = function (cb) { work.onmessage = cb; };
    wrapr.error = function (cb) { work.onerror = cb; };
    work.postMessage(true);
    return wrapr;
};
    var mtd = "self.onmessage = function() {postMessage(" + _function.toString().replace('(','du(') + "(" + JSON.stringify(data) + "));};";
    blob = new Blob([mtd], { type: 'application/javascript' });
    var work = new Worker(URL.createObjectURL(blob));
    wrapr.ready = function (cb) { work.onmessage = cb; };
    wrapr.error = function (cb) { work.onerror = cb; };
    work.postMessage(true);
    return wrapr;
};
/////////////////////////////////////////usage/////////////////////////////////


var extensiveMath = function (a) {
    var e;
    for (var i = 0; i < 100000; i++) {

        for (var ah = 0; ah < 100040; ah++) {
            e = i * Math.E / -i;
        }
    }

    return e - a;
};


var core1 = wrapworker(extensiveMath, 1234567890)
.ready(function (result) {
    console.log("core1 done", result);
});

var core2 = wrapworker(extensiveMath, 1234567890)
.ready(function (result) {
    console.log("core2 done", result);
});

var core3 = wrapworker(extensiveMath, 1234567890)
.ready(function (result) {
    console.log("core1 done", result);
});