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The stuff after trailing slashes in regexps
filburt1
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filburt1 filburt1 is offline 05-24-2003, 10:00 PM

It took quite a bit of research, but here's what those characters after regular expressions mean:
  • i: case-insensitive
  • c: effectively means return what doesn't match the expression
  • m: don't ignore whitespace differences
  • s: ignore multiple lines when using the match chars (*, ?, +, etc.)
  • x: allow whitespace and comments (for readability)
  • U: don't be greedy
I still can't figure out what U does (vB uses //siU everywhere), but those five are the common ones.
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Old 05-25-2003, 01:44 AM
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What does the i do in siU?
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Old 05-25-2003, 01:45 AM
filburt1 filburt1 is offline
 
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Case-insensitive (stupid JS-based vB code generator...)
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Old 05-25-2003, 10:17 AM
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Quote:
Today at 05:16 AM filburt1 said this in Post #1
I still can't figure out what U does (vB uses //siU everywhere), but those five are the common ones.
U specifies "greediness". Roughly that is whether search returns the largest matched pair or the smallest, if there are more than 1 matches.
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Old 05-25-2003, 12:10 PM
filburt1 filburt1 is offline
 
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But isn't .? used for that (rather than .*)?
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Old 05-25-2003, 03:07 PM
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Say you have this text:
Quote:
aaaaa
[bbb]
ccccccccccccc
[bbb]
dddddddddddd
[/bbb]
eeeeeeeee
[/bbb]
ffffffffffff
and you are trying to match chars between [bbb] tags. Would your regular expression return:
Quote:
dddddddddddd
or:
Quote:
ccccccccccccc
[bbb]
dddddddddddd
[/bbb]
eeeeeeeee
that is what greediness parameter specifies.
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Old 05-25-2003, 03:08 PM
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I know what it means, I mean that isn't that what the ? operator is used for rather than the * operator?
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