Show HN: Matches.js -- Powerful Pattern Matching for Javascript

Cool! Sucks that it has to be so stringly typed, but I can't see another alternative.<p>One concern:<p>"Each pattern will be tried in order until a match is found."<p>As far as I know, ECMAScript doesn't specify any enumerations on objects that obey an order... browsers do syntactic order, but it's by no means a guarantee. (e.g. <a href="http://stackoverflow.com/a/280861" rel="nofollow">http://stackoverflow.com/a/280861</a>)

I didn't know I needed this until I saw it and had that A-HA moment when I realized how much cleaner this would make a lot of code. Instead of hiding away the logic in a bunch of conditionals this makes the overloading declarative which is great for maintenance.

What are some applications of pattern matching?

I've played a bit with pattern matching as a DSL on top of JavaScript: <a href="http://jsfiddle.net/ntoshev/q8Ayw/1/" rel="nofollow">http://jsfiddle.net/ntoshev/q8Ayw/1/</a>

I've come across aspects of this functionality before in a couple of languages now, even psql, however looking at this JavaScript way of doing it, I have to question whether it helps code readability or hurts it.<p>edit: dyslexia

For those interested: XRegExp (<a href="http://xregexp.com" rel="nofollow">http://xregexp.com</a>) is also relevant.<p>(Not a direct competitor to Matches.js, but has some nice features)

Something like this would make a great addition to CoffeeScript.

i want this in js for a long time

Awesome! This is so useful!