Wow. That's news to me.

I wonder what else is in the JS syntax that I've been missing out on!

4 spaces and you can get code styling:

    Like this

Or rather

    outer: for (var i = 0, j = 0; i < nlen; i++) {
        var nch = needle.charCodeAt(i);
        while (j < hlen) {
          if (haystack.charCodeAt(j++) === nch) {
            continue outer;
          }
        }
        return false;
      }

I don't know why the author coded it this way, it can be done much simpler:

    function fuzzysearch(needle, haystack) {
        var hlen = haystack.length;
        var nlen = needle.length;
        
        if (nlen > hlen) return false;
        if (nlen === hlen) return needle === haystack;
        
        for (var i = 0, j = 0; i < nlen; ++i, ++j) {
            while (j < hlen && needle.charCodeAt(i) !== haystack.charCodeAt(j)) ++j;
            if (j === hlen) return false;
        }

        return true;
    }

He says the algorithm was suggested by "Mr. Aleph, a crazy russian compiler engineer working at V8.". It's possible it was suggested to be written this way because V8 (and possibly other interpreters) can optimise it to be faster.

It's written with continue precisely to avoid additional `if (j === hlen)` check after the loop and having a single increment of `j` in the loop :)

To be honest reasoning about the loop with continue is actually easier than about one without.

Yes, but it is typically frowned upon. Here's and MDN on it: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe...

Though in this case, it's a crazy performance hack from Vyacheslav Egorov. Check out the graph: https://cloud.githubusercontent.com/assets/934293/6550014/d3...

I would not call it a performance hack, it's just a readable way to write an algorithm - most important part of my original suggestion was actually to use x.charCodeAt(i) instead of x[i]

I wanted to actually ask the same thing! I knew of continue but I never encountered such a scenario. It's a poor man's generator.

In other languages (such as PHP), the same thing can sometimes be achieved by using "break N" / "continue N", where N is the number of loop you wish to break/continue.

Specifically in PHP, though, you can't (anymore) break a variable value.

break $n;

isn't valid since PHP 5.4