Hi Jared,
At 5/30/2007 06:00 PM, Jared Farrish wrote:
>>Read the manual:
>
>All due respect, I did read it. It's just... a little dense and not
>practically descriptive.
Sorry, I didn't mean to be disrespectful, I thought your question was
more elementary than it was. There are, though, a ton of regular
expression resources on the net. Google Is Your Friend. I just got
a million hits on 'regular expression tutorial.'
>Maybe it's more practical to ask, "When is it practical to use it?"
>
>It matches anything, so I ***ume that means you can use it to match, say, a
>paragraph that you can't predict or match against? One that you're looking
>for a pattern match on one or either end?
Well, sure. It often appears as .* meaning "none or any number of
any characters." Use it when you honestly don't care what it matches.
Say you want to find out if the word "frog" occus in a text followed
by the word "dog." You could match on:
/\bfrog\b(.*\b)?dog\b/i
/ pattern delimiter
\b word boundary
frog 1st word
\b word boundary
( begin subpattern
..* zero or any characters
\b word boundary
) end subpattern
? zero or one instance of the preceding subpattern
dog 2nd word
\b word boundary
/ pattern delimiter
i case-insensitive
This guarantees that both words are bounded by word boundaries and
allows any number of any characters to occur between them. (There's
sort of an implicit .* before and after the pattern. Because I
haven't used ^ and $ to define the beginning and end of the text,
regex looks for my pattern anywhere in the text.)
>And why is it called full stop?
That's what the 'period' is called in British English.
http://google.ca/search?q=define%3Afull+stop
In English syntax "period" and "full stop" are synonymous, and the
RegEx manual is throwing "dot" into the same bag.
Regards,
Paul
__________________________
Paul Novitski
Juniper Webcraft Ltd.
http://juniperwebcraft.com