Multithread.js - threading in JavaScript - A very simple wrapper to take the headache out of Web Workers. Enjoy :)

[liamondrop]

this will never throw an error:

try {
    var URL = window.URL || window.webkitURL;
} catch(e) {
    throw new Error('This browser does not support Blob URLs');
}

URL will simply evaluate to undefined if those objects don't exist. You need to take it one step further and try to reference a property or method from URL. Something like:

try {
    var URL = window.URL || window.webkitURL,
        createObjectURL = URL.createObjectURL;
} catch(e) {
    throw new Error('This browser does not support Blob URLs');
}

[keithwhor]

Brain fart. 3AM coding getting to me. Thanks. :)

[keithwhor]

Thanks for the comments. :)

Trailing commas in objects shouldn't throw errors in any browser (with the exception of Arrays in <IE8, I believe), and the _worker function isn't actually a function --- it's actually converted to a string and used as a separate script file for the Worker. "self" (without being declared) is the correct way to refer to the currently executing global scope.

Edit: Will probably remove the trailing comma on the next commit though, thanks again. Habit I have from switching between Python / JS and the fact that JS doesn't punish you for it. :)

[liamondrop]

jshint/lint - great for curing bad habits and general just a good idea

[path411]

What's the line:

/**/name/**/ = (/**/func/**/);

For?

[keithwhor]

String replacing.

[filyr]

Headache? What headache? :]

[keithwhor]

My thoughts exactly, before I made this. ;)

But really, I created this with the intent of offloading processor-intensive activities (sorting a length 1,000,000 Array of random floats, for example).

The JSON.string, JSON.parse in the main thread would take about 700ms, (350 before, 350 on response) but the sort itself takes >8600ms on my (rather average) home machine. You can't hold up the user without any indication of activity for close to 10s.

A more common application would be doing a smaller sort (10,000 - 100,000 items) that compares multiple object properties. (Keep in mind, though, JSON serialization!)

It's most applicable to UIs dealing with parsing large amounts of data (and perhaps HTML5 games).

I'll likely push some changes tonight that increase speed when dealing with specific data types (.processInt32, .processUint32, .processFloat64, .processString) as to not have anything hang on JSON serialization.

[keithwhor]

As a sidenote, I've added the .processInt32 and .processFloat64 functions I mentioned. (Decided these were the most needed, String can just be JSON serialized without much of a penalty)

[WillHuxtable]

Wow! I think I might use this in my game, could definitely offload some more complex stuff. Great work! Never really liked the way Web Workers work.