Hi,

my problem:

I've got a single string, containing the contents of a complete HTML-File (including CarriageReturns). This string contains several <table>...<\table> parts (with a lot of linebreaks in the ... part).

What I want to do is to get the first table from the string.

What I tried: 
my $html="<table>\nt1\n<\/table>\n<table>\nt2\n<\/table>\n"

$html =~ m/<table>(.*?)</table>/;   
# Failed, since 'The period '.' matches any character but ``\n''

$html =~ m/<table>(.*?)</table>/s;   
# SUCCESS, since 's modifier (//s): Treat string as a single long 
# line. '.' matches any character, even "\n"'

$html =~ m/<table>[a-zA-Z0-9 \r\n<>"!-=]*?</table>
# SUCCESS - Emulating '.' with defining a own character class, 
# containing 'any' characters (or a subset in this example) including 
# '\n'
# NO s modifier (//s) needed

$html =~ m/<table>[.\n]*?</table>;
# Same as above, but using '.' instead of explicitly listing all 
# characters ...
# Failed, WHY? Why is '.' not allowed within a character class?

[download]
Further investigation shows, that [.] is not a valid character class ...

My questions are:

Why is '.' not allowed within a character class?

It's clear to me now that my desired character class [.\n] can be achieved with the s modifier - but why is there such an "inconsistent way" using a modifier to emulate a character class?

Why is there no "super" character class - matching ALL characters including '\n'?

What's the reason excluding '\n' from '.'? (Why is '\n' handled in a special way?)

Hoppfrosch

Edit by castaway - use html entities instead of angled brackets

In reply to RegEx: Why is [.] not a valid character class? by hoppfrosch

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