REALLY simple xml reader

Ben Finney bignose+hates-spam at benfinney.id.au
Thu Jan 31 15:51:56 EST 2008


Steven D'Aprano <steve at REMOVE-THIS-cybersource.com.au> writes:

> On Fri, 01 Feb 2008 00:40:01 +1100, Ben Finney wrote:
> 
> > Quite apart from a human thinking it's pretty or not pretty, it's *not
> > valid XML* if the XML declaration isn't immediately at the start of the
> > document <URL:http://www.w3.org/TR/xml/#sec-prolog-dtd>. Many XML
> > parsers will (correctly) reject such a document.
> 
> You know, I'd really like to know what the designers were thinking when 
> they made this decision.

Probably much the same that the designers of the Unix shebang ("#!")
or countless other "figure out whether the bitstream is a specific
type" were thinking:

It's better to be as precise as possible so that failure can be
unambiguous, than to have more-complex parsing rules that lead to
ambiguity in implementation.

Also, for XML documents, they were probably thinking that the
documents will be machine-generated most of the time. As far as I can
tell, they were right in that.

Given that, I think the choice of precise parsing rules that are
simple to implement correctly (even if the rules themselves are
necessarily complex) is a better one.

-- 
 \       "Those who will not reason, are bigots, those who cannot, are |
  `\        fools, and those who dare not, are slaves." —"Lord" George |
_o__)                                                Gordon Noel Byron |
Ben Finney



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