Jacques,

Did you download that PDF file I mentioned previously? Also, there is a UEL 
tutorial:

http://java.sun.com/javaee/5/docs/tutorial/backup/doc/JSPIntro7.html

-Adrian


--- On Fri, 12/19/08, Jacques Le Roux <[email protected]> wrote:

> From: Jacques Le Roux <[email protected]>
> Subject: Re: Discussion: Unified Expression Language Functions
> To: [email protected]
> Date: Friday, December 19, 2008, 9:27 AM
> From: "Adrian Crum" <[email protected]>
> > Adam Heath wrote:
> >> David E Jones wrote:
> >>> This may be a novel idea... but you could
> always test them and see if
> >>> they work or not... ;)
> >> 
> >> How about we keep the current custom parser, but
> then add uel as a
> >> prefix, like ${bsh:} is, then issue warnings for
> strings that don't
> >> match a prefix, giving the line number/file of the
> string.
> >> 
> >> I think it'd be better to not have a default
> language there, and always
> >> explicitly request a particular language for
> interpetting.
> >> 
> >> Of course, there's one other major problem,
> finding the end of the
> >> token.  Take for instance, the following String:
> >> 
> >> toProcess =
> "foo${bsh:\"abc\"+123+\"}\"}";
> >> 
> >> Finding the matching {} there is difficult, if you
> can't have a unified
> >> parser for the multiple languages.
> >> 
> >> ps: You could say that fixing the above could be
> done by escaping the
> >> internal '}'.  But then you'd have
> java-source-level escaping,
> >> StringExpander-level escaping, chosen language
> escaping, etc, all
> >> conflicting/overlapping with each other.
> > 
> > The home-grown parser is very limited. In the original
> FlexibleMapAccessor code, it just scanned the expression for
> a period and assumed any period found was a Map element
> delimiter. Problem is, there could be periods anywhere in
> the expression that aren't Map element delimiters.
> > 
> > My preference is to replace the home-grown parser with
> the JUEL parser - because it is far more sophisticated and
> has been thoroughly tested.
> > 
> > I also prefer to have UEL as the default language for
> ${} expressions - because it is well known, well documented,
> and very powerful.
> 
> Maybe a bit enthusiast and not very well documented at this
> stage, but my feeling is +1
> 
> Jacques
> 
> > -Adrian
> > 
> >


      

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