On Wed, 14 Aug 2002, Ralf G. R. Bergs wrote:
> rabe@??? \
> "${if and {
> {def:h_To:}
> {match
> {$h_To:}
> {\\N^(\"someone@???\" )?<?someone@???>?$\\N}
> }
> } {rabe-lkt} fail
> }" fFrQ
>
> I've broken the line to make it more readable, I hope it's still obvious how
> the expression looks like.
>
> The pattern recognizes addresses like the following:
>
> "someone@???" <someone@???>
> <someone@???>
> someone@???
>
> Is this, in your eyes, the optimal way of writing this, or can you give me
> additional hints about how to further improve it?
1. You don't really need the def:h_To: condition, because if there is no
To: header, $h_To: expands to an empty string.
2. Your regex will also match
"someone@???" someone@???
<someone@???
someone@???>
but as those are illegal (and should never happen), it doesn't really matter.
3. Perhaps more imporantly, your regex will also match
someone@somewhere+org
etc. For tidiness, it is best to escape the dots.
4. Do you care about multiple spaces between the two parts?
5. A slightly more efficient regex would use (?:...) instead of (...) to
save some work, but it will only be very slightly more efficient.
--
Philip Hazel University of Cambridge Computing Service,
ph10@??? Cambridge, England. Phone: +44 1223 334714.
