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Date: Wed,  4 Mar 2009 10:41:34 +0100
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From: Rudolf Sykora <rudolf.sykora@gmail.com>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
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Subject: Re: [9fans] command repetition in sam/acme
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> Sam and Acme use a simple, pure form of regular expressions. =A0If they
> had the counting operations, this would be a trivial task, but to add
> them would open the door to the enormous, ill-conceived complexity of
> (no longer) regular expressions as the open source community thinks of
> them.

Is it really so? R. Cox (Regular Expression Matching Can Be Simple And
Fast), I think, shows, that repetition can be first expanded and then
used even by the nice (non-backtracking) algorithms, like this:

e{3} --> eee
e{3,5} --> eeee?e?
e{3,} --> eee+

where would the problem arise?

Thanks
Ruda

>
> So yes: use other tools, with my apologies.
>
> -rob