Re: [Webit-discuss] Re: sxml-match patterns

Oleg,

Thank you for your answer. I have been using sxslt until now, and
moved towards sxml-match because of its (elegant!) macro-ish matching
syntax and the fact that attribute matching is under-ordered. The
latter is a feature I find particularly useful for my problem. (STX
does not seem to possess it, from what I could see.)

I had not considered combining sxslt and sxml-match together. I shall
give it a try.

Still, it would be interesting to find out the reason the stylesheet
in my previous message generates the same tag twice.

Also, I found two strange (to me) legal sxml-match stylesheets:

;; a) infinite loop at runtime
(sxml-match sxml
  (,[x] x)))

;; b) runtime error "undefined variable x" 
(sxml-match sxml
  (,[x] (guard (string? x)) x)))

I cannot quite figure out the rationale behind the grammar[*]
specifying that a node can be a catamorphism.

[*] http://celtic.benderweb.net/sxml-match/manual/index.html

Thank you,
___
Alessandro



On 5/25/05, [email protected] <[email protected]> wrote:
> 
> 
> Hello!
> 
>         This is a reply to a message by Alessandro Colomba
> on the webit-discuss mailing list:
>   http://sourceforge.net/mailarchive/forum.php?thread_id=7330228&forum_id=15740
> 
> The message might be of interest to other SXML users.
> 
> Alessandro Colomba wrote:
> 
> > Attempting to write a stylesheet to walk through an entire document,
> > and match inner elements, I could not find a way to express something
> > like:
> >
> > <!-- the identity transform -->
> > <xsl:template match="@*|node()">
> >   <xsl:copy>
> >     <xsl:apply-templates select="@*|node()"/>
> >   </xsl:copy>
> > </xsl:template>
> > Initially, wanting to copy a tree and transform only select elements,...
> 
> It may be helpful to exploit the strengths of traversal and matching
> (querying). Although you can use traversal for querying/matching (by
> mapping non-matched or uninteresting elements to nothing) and
> querying/matching for bulk transformations, that doesn't seem to be
> the best use of either tool. The identity transform has the following
> simple form in SXSLT:
> 
>         (pre-post-order sxml
>          `((*text* . ,(lambda (tag str) str))
>            (*default* . ,(lambda node node))))
> 
> You can add more rules to transform some nodes differently. Please see
> examples in SSAX/examples (in the CVS repository or in a SSAX
> distribution). In particular, sxml-nesting-depth-label.scm
> 
> It should be stressed that each SXSLT handler receives a node. So, a
> handler can use sxml-match to match/transform just that particular
> node. You can leave the rest of the traversing to pre-post-order
> engine.
> 
> If you're interested in translating XSLT stylesheets, you might want
> to take a look at STX,
>         http://www196.pair.com/lisovsky/transform/stx/
> and     http://www196.pair.com/lisovsky/query/
> 
> 
>         Cheers,
>         Oleg
> 
> 
> -------------------------------------------------------
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> 




On 5/25/05, [email protected] <[email protected]> wrote:
> 
> 
> Hello!
> 
>         This is a reply to a message by Alessandro Colomba
> on the webit-discuss mailing list:
>   http://sourceforge.net/mailarchive/forum.php?thread_id=7330228&forum_id=15740
> 
> The message might be of interest to other SXML users.
> 
> Alessandro Colomba wrote:
> 
> > Attempting to write a stylesheet to walk through an entire document,
> > and match inner elements, I could not find a way to express something
> > like:
> >
> > <!-- the identity transform -->
> > <xsl:template match="@*|node()">
> >   <xsl:copy>
> >     <xsl:apply-templates select="@*|node()"/>
> >   </xsl:copy>
> > </xsl:template>
> > Initially, wanting to copy a tree and transform only select elements,...
> 
> It may be helpful to exploit the strengths of traversal and matching
> (querying). Although you can use traversal for querying/matching (by
> mapping non-matched or uninteresting elements to nothing) and
> querying/matching for bulk transformations, that doesn't seem to be
> the best use of either tool. The identity transform has the following
> simple form in SXSLT:
> 
>         (pre-post-order sxml
>          `((*text* . ,(lambda (tag str) str))
>            (*default* . ,(lambda node node))))
> 
> You can add more rules to transform some nodes differently. Please see
> examples in SSAX/examples (in the CVS repository or in a SSAX
> distribution). In particular, sxml-nesting-depth-label.scm
> 
> It should be stressed that each SXSLT handler receives a node. So, a
> handler can use sxml-match to match/transform just that particular
> node. You can leave the rest of the traversing to pre-post-order
> engine.
> 
> If you're interested in translating XSLT stylesheets, you might want
> to take a look at STX,
>         http://www196.pair.com/lisovsky/transform/stx/
> and     http://www196.pair.com/lisovsky/query/
> 
> 
>         Cheers,
>         Oleg
> 
> 
> -------------------------------------------------------
> SF.Net email is sponsored by: GoToMeeting - the easiest way to collaborate
> online with coworkers and clients while avoiding the high cost of travel and
> communications. There is no equipment to buy and you can meet as often as
> you want. Try it free.http://ads.osdn.com/?ad_id=7402&alloc_id=16135&op=click
> _______________________________________________
> Webit-discuss mailing list
> [email protected]
> https://lists.sourceforge.net/lists/listinfo/webit-discuss
>


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