Support native String.trim

[peller]

ECMAScript 3.1 will support String.trim, and FF 3.1 is advertising support for this. Other browsers will follow.

[peller]

str.trim is shorter than "trim" in str, but either seems reasonable

[dante]

are we sure prototype doesn't add a .trim() method to String.prototype ? For some reason, this doesn't feel right ... are there any subtle differences in FF's .trim() impl and ours?

[peller]

I suggest we get it in SRTL. This one's a lot simpler than query. The only possible discrepancy is whether we use the same set of chars -- whitespace should match what RegExp? uses, iirc; not sure about LineSeparator?.

From the ES 3.1 08-11-2008 draft:

15.5.4.20 String.prototype.trim ( ) If this object is not already a string, it is converted to a string. The result is a copy of the string with both leading and trailing white space removed. The definition of white space is the union of WhiteSpace? and LineTerminator?. The result is a string value, not a String object. NOTE The trim function is intentionally generic; it does not require that its this value be a String object. Therefore, it can be transferred to other kinds of objects for use as a method.

I don't see a trim() method in prototype-js (kinda surprising... they must have one?) but I do see one in MS Ajax.net, and sure, other toolkits could define one. So what? I'm sure there are plenty of other places where buggy overrides could mess us up, but this one is important enough to be in a new standard, and the behavior is pretty straight-forward.

[dante]

+1

[peller]

(In [16231]) Use native String.trim() where available. Fixes #8182

[elazutkin]

Why not implement it like that (pseudo code):

dojo.trim = String.prototype.trim || function(s){ /* our trim */ };

This way we don't check if the standard trim is available on every single call.

[peller]

(In [16238]) Update docs to indicate native String.trim() is used. Refs #8182

[peller]

Replying to elazutkin:

Why not implement it like that (pseudo code): {{{

dojo.trim = String.prototype.trim function(s){ /* our trim */ }; }}} This way we don't check if the standard trim is available on every single call.

Good suggestion -- I should have done something like this -- but it seems at a minimum, you need a call (though I'm not sure why offhand) at which point, we start to add some bloat. I worry a bit less about bloating dojo/string.js than base, though I'm starting to think with native methods dojo.string.trim is just bloat itself.

[elazutkin]

(In [16239]) Restructuring dojo.trim() and dojo.string.trim() to make a choice (native vs. manual) only once during the loading time. !strict. Fixes #8182.

[elazutkin]

(In [16240]) Reducing the code by several bytes and improving the load time a little, !strict, refs #8182.

[peller]

(In [16241]) Remove unneeded call to str.trim(). Refs #8182