in reply to Re: xml parsing without using cpan modules
in thread xml parsing without using cpan modules

And more importantly, he knows the XML generators whose output he is dealing with, which means he doesn't have to account for all plausible cases — only those the generators he is dealing with take advantage of.

If you want to deal with XML in the general case, then you do have to parse, no way around it.

Makeshifts last the longest.

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Re^3: xml parsing without using cpan modules
by iburrell (Chaplain) on Aug 10, 2004 at 19:07 UTC
    It is possible to write an XML parser using regular expressions. Check out "REX: XML Shallow Parsing with Regular Expressions", http://www.cs.sfu.ca/~cameron/REX.html. It even has Perl code for doing.

    It effectively splits the XML into a list of strings on logical boundaries by repeating a regular expression that matches XML markup. It is fairly easy to find the type of each chunk by looking at the first couple of characters.

[reply]

      Of course you can parse using regular expressions. You just shouldn't grope around in a string representing an XML document using regular expressions, because you have to be certain about the context in which any match occured. That means you have to scan the string strictly front-to-back, probably using the /gc options and the \G anchor to make sure you don't miss anything. Simply picking matches out of the middle of the string is very likely to be a broken approach unless you are dealing with a known subset of XML syntax.

      Makeshifts last the longest.

[reply]
        Absolutely. That regex only works because it starts at a known position (start of markup) and matches either the entire chunk or fails. It needs to see the entire document and can't work line-by-line. It is also complicated to handle the whole XML synax.
[reply]
        Could you please be bit clear?

        Thanks & Regards

        Nalina
[reply]

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