Re: extracting a substring from a string

Is the data some sort of home-grown imitation of XML? If it was "real" XML, there wouldn't be a slash before the first close-angle-bracket. (I guess since it isn't real XML, it wouldn't help to recommend an XML parsing module.)

Do you mean something like this?

my $string = '...blah...<file fiop="foo" length="bar"/>baz</file>...bl
+ah...';

my ( $foo, $bar, $baz );
if ( $string =~ s{<file fiop="([^"]+)" length="([^"]+)"/>([^<]+)</file
+>}{} ) {
    ( $foo, $bar, $baz ) = ( $1, $2, $3 );
    print "extracted $foo, $bar, $baz; left $string\n";
}
[download]

Comment on Re: extracting a substring from a string - multiple variables Download Code

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Re^2: extracting a substring from a string - multiple variables by walinsky (Scribe) on Oct 27, 2007 at 23:10 UTC
Actually you hit it right on the spot; it's home-grown XML from Cupertino... The baz part is raw binary data, inserted in the XML; that's why I want to extract it before parsing the valid XML. I hadn't even noticed the close-angle-bracket (thanks - but it's really there). I've tried your code; but it doesn't seem to get me there. Any further suggestions ?	[reply]
Re^3: extracting a substring from a string - multiple variables by graff (Chancellor) on Oct 27, 2007 at 23:48 UTC
When I run my snippet as posted, I get the following output: `extracted foo, bar, baz; left ...blah......blah...` [download] Do you get something different when you run it? Or do you want something different from that? When you try to use the "s{...}{}" expression in your own code, is it possible that your "raw binary data" (in "the baz part") might contain a byte value of 0x3C? This would be treated as a "<" character in the regex match, which would cause trouble. Something like this might work better in that case: `s{<file fiop="([^"]+)" length="([^"]+)"/>(.?)</file>}{}s` [download] (update: added the "s" modifier at the end, in case the raw binary stuff might contain a line-feed) Note the question mark after "." -- that's the important thing that was missing from your initial attempt: it makes the wildcard match non-greedy (stops matching as soon as possible).	[reply] [d/l] [select]
Re^4: extracting a substring from a string - multiple variables by walinsky (Scribe) on Oct 28, 2007 at 00:41 UTC
where do I send the flowers ;) the 's' modifier at the end did the trick! thanks for your continuous effort (and updating your comment ;)	[reply]
Re^2: extracting a substring from a string - multiple variables by duff (Parson) on Oct 29, 2007 at 13:46 UTC
I find it funny that the right solution ("use a parser") is shot down because this isn't exactly XML. Are you sure an HTML parser wouldn't parse it properly? Weird how everyone gets stuck on regex. duff	[reply]


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Re: extracting a substring from a string - multiple variables