[TxMt] Performance issues

[Timothy Reaves]

On May 26, 2006, at 5:14 PM, Jonathan Ragan-Kelley wrote:

>> Regular Expressions can do an awful lot in the arena of
>> text processing; but a lot of what an editor used by programmers
>> needs to do can not be done at all, or at least very well, by over
>> reliance on Regular Expressions.
>
> While I agree with the desire for ever more powerful mechanisms, I'd
> like to speak up quickly just to say that what Allan has effectively
> created with the scope system, used both for styling and for
> commands/etc. is a real parser -- a CFG or set of CFGs -- not a mere
> regular expression, because of the ability to nest elements in a
> language grammar.  Just like in a conventional machine language
> parser, regular expressions are used to recognize individual parse
> elements, but the structure it generates and uses to analyze and
> represent the code or other file contents is context-free, and hence
> just about as powerful as anything used in other editors, even up to
> the level of Eclipse's fancy-dan refactoring tools and so forth.  What
> could make this more accessible for more advanced tools might be a
> more direct API to run over (and potentially transform) the parse
> tree, not just the current context, but what it does now is still much
> more powerful than mere regular expressions.
> -jrk


	While in general I agree with this, Ill make two points:

1) saying it's up to par with Eclipse is just laughable, and so self- 
evidently false that I'll leave it at that.  Anyone wanting to debate  
the finer points of this are welcome to, but I'm not sure the list is  
up to it.  :)  Just e-mail me directly.

2) I have no problem calling it more that RegEx; call it what you  
will.  It is powerful, and can do wonders.  I'm impressed with it's  
abilities.  But.  It is still BUILT upon RegEx, and runs a RegEx  
engine, and therefore, is going to be much slower that what Eclipse,  
Visual SlickEdit, and BBEdit provide (just the editors of these  
products; not the full products).