Hi Rick,

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Well one problem with this thinking is that if you want to do something with
the document you pretty much need a DOM parser.
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Not sure why you're saying that. I'd bet that most of the better XSLT processors today are built on SAX. I exempt MS's, but that one has gotten so much faster in recent releases anything is possible <s>.

IAC... the whole point is that XSLT processors *don't* "walk the document to find things" the way you might think.

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In order to do things like XPath or even XSLT you a DOM in order to
be able to walk the document or find things...
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Yes XSLT uses XPATH. But it can use XPATH very efficiently.

XSLT makes efficient use use of indexes. So it isn't necessarily walking the huge document when it uses XPATH. <s>

I've done lots of timing tests, in many different XSLT processors <s>. The results are pretty dramatic. Yes, it's possible to write inefficient XSLT but novices can write lousy SELECT statements too.

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It's kind of like saying you can use only a SCAN loop in VFP, but not the SELECT statement...
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Well, first of all, in VFP and elsewhere, issuing the SELECT statement creates internal workfiles that will transparently move from disk to memory as need be. Right? I'm saying that the same thing will eventually happen for DOM parsers if it hasn't already. Even for the DOM, the issue ends when this happens.

On the SAX side: you may imagine what SAX does as something like a SCAN with a whole bunch of relations set, and this may be more-or-less accurate <s>.

But remember that in XSLT, it's not a linear or forward-only experience at all, even so.

In general, it's important to remember that XSLT is a declarative syntax. You declare your intent, you don't tell the processor what to execute, or in what order.

If you do a lot of xsl:call-template or xsl:for-each (versus xsl:apply-templates) you probably think you know what order things are happening in -- but you really do not.

>L<