Comments on: Faster JavaScript Trim

By: Erik Landvall

Erik Landvall — Tue, 09 Mar 2010 12:48:08 +0000

I rewrote trim12 somewhat…
I don’t know if it’s as fast as the original, but can’t see why it would’nt be.

String.prototype.trim = function(){
return this.triml().trimr();
};

String.prototype.triml = function(){
return this.replace(/^\s\s*/, ”);
};

String.prototype.trimr = function(){
    var ws = /\s/,
        i = this.length;
    while(ws.test(this.charAt(–i)));
    return this.slice(0, i + 1);
};

By: Dan

Dan — Sun, 03 Jan 2010 08:17:50 +0000

I read this article some years ago and found it very useful, I will use trim12 because of shorter code and still good performance, thanks.

By: Elixir » Blog Archive » Javascript Trim

Elixir » Blog Archive » Javascript Trim — Thu, 24 Dec 2009 12:05:46 +0000

[...] Credit. I made it available to the String prototype. Read [...]

By: RobG

RobG — Thu, 17 Dec 2009 01:44:34 +0000

Seems this won’t be needed in the future as ECMAScript Ed. 5 includes String.prototype.trim. And of course all browser vendors will rush to implement it immediately.

Otherwise, an interesting post. It may appear to be premature optimisation, however it shows that while some algorithms are very fast in some browsers, they may also be very slow in others. It’s good to use an algorithm that is reasonably fast in a representative cross-seciton.

By: Andrew Garrett

Andrew Garrett — Thu, 26 Nov 2009 11:55:34 +0000

This looks suspiciously like premature optimisation, I’m not sure how many cases there are where trim() is really performance-critical.