Re: [FWP] japhy had a silly idea...

[Michael Salmon <ms@speakeasy.net> (by way of owner-fwp@technofile.org)]

>From fwp-l Sat May 26 18:26:23 2001

On Sat, May 26, 2001 at 06:11:24PM -0400, Ronald J Kimball wrote:
> On Fri, May 25, 2001 at 10:57:46PM -0400, Mark Rogaski wrote:
> > An entity claiming to be Abigail (abigail@foad.org) wrote:
> > :
> > : BTW, an interesting exercise would be to prove that a certain regex
> > : only matches a certain set of strings, and no other strings.
> > :
> >
> > If you mean that the sets are finite, then the regex cannot include *, +,
> > or any other unbounded repetition.
> >
>
> Why do the sets have to be finite?
>
> Anyway, here's a degenerate regex that includes + but matches a finite set
> of strings:
>
> /a+^/

that matches an unbounded set of strings. remember, there is more then 1
infinity. there are infinite infinities!

a aa aaa aaaa aaaaa .................................... (infinity)

(:

> :)
>
> Ronald
>

ms-

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