From: "David A. Black" <dblack@...>
Date: 2008-06-21T16:50:41+09:00
Subject: Re: RegEx

Hi --

On Sat, 21 Jun 2008, Justin To wrote:

>
>
> Wonderful help guys!
>
> One other question related to that last bit:
>
> match(/(v4.|v 4.|-4-/))
>
> Would this also match the '(' and ')' ? Or are the parentheses grouping
> the items in this case?

They're grouping items. (And see Wayne's correction.)

The hard thing about character classes:

   /abc[def]/

is that the character class itself takes up horizontal space on your
screen, but it actually only represents one character in the string,
in the case a 'd', 'e', or 'f'. It's almost like a vertical construct,
like a slot machine:

     [d]
/abc[e]/
     [f]

where only one of the values described in the character class is
actually going to match.

Of course, if you have a modifier like +:

   /abc[def]+/

then the + means that the character class can match more than once.
But each time it matches, it's still only consuming one character in
the string.


David

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