Re: Re: Re: Re: preg_match() returns false but no documentation why

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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.

This is what I thought it meant. Your example more than clears it up.

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.)

Very helpful! I still have questions, but a PHP mailing list probably isn't
the best place.

>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.

That's very confusing to call it 'Full Stop' when it doesn't seem to
actually correlate to the regex meaning it identifies, don't you think?
Maybe to a Brit or someone who understands Commonwealth English would know
(I was aware of what it meant in CE, I just woudn't have imagined to apply
it here, since it looks to be descriptive).

Kind've like an elephant trainer calling her elephant's trunk a boot.

--
Jared Farrish
Intermediate Web Developer
Denton, Tx

Abraham Maslow: "If the only tool you have is a hammer, you tend to see
every problem as a nail." $$

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