Improving String.strip performance

[disccomp]

Please see this excellent breakdown of this function on cross-browser
performance to better understand the available solutions.
http://blog.stevenlevithan.com/archives/faster-trim-javascript

[John-David Dalton]

Also some other performance tips:
http://www.sitepen.com/blog/2008/05/09/string-performance-an-analysis/

disccomp, feel free to submit a ticket and a patch for the current
String#strip
http://www.prototypejs.org/contribute

- JDD

[Ken Snyder]

Awesome analysis!

I wonder if trim12 might be improved by avoiding calling slice if there
is no trailing white space:

function trim12 (str) {
var str = str.replace(/^\s\s*/, ''),
ws = /\s/,
i = str.length,
len = i;
while (ws.test(str.charAt(--i)));
return i + 1 < len ? str.slice(0, i + 1) : str;
}

Also, you did not say it explicitly, but are you saying that /\s/.test()
is faster than whitespace.indexOf() ?

- Ken

[disccomp]

I'd prefer if someone already involved in the project would use the
analysis to create the ticket, patch, etc..