On Sun, Apr 29, 2007 at 11:24:16AM -0500, Tim Chase wrote:
> > Five identical characters would be: /\[a-z,A-Z]\{4}/ I believe...
>
> This would be any 4 characters in your set [a-z,A-Z] (including
> the comma), it would match any of the following:
>
> aaaa
> ,,,,
> ZZZZ
> A,b,
> ,A,Z
>
> > Numbers would be: /\d\d\{2}\d/
>
> This also would match things like
>
> 1221
> 1222
> 1223
> 2114
> 1234
>
>
> For both cases, you need to tag something (or multiple
> somethings) with the "\(...\)" syntax and then reference back to
> it with "\1" to get the exact same character:
>
> \([a-zA-Z]\)\1\{4}
> \(\d\)\(\d\)\2\1
>
> Otherwise, the repetition (the "\{...}") allows any match of the
> previous pattern-atom rather than the resulting matched-atom.
> Thus, your first pattern would be equivalent to
>
> [a-z,A-Z][a-z,A-Z][a-z,A-Z][a-z,A-Z]
>
> Hope this helps clarify things...
>
> -tim
>
>
Yes, you're right. Thank you very much!
/iveqy
