Re: Combining 2 preg matches.

frizzle wrote:
$regex ='/^(?:[a-z]|[a-z][_\-][a-z])+$/';

...will do just fine.

equally so:
$regex ='/^(?:[a-z]+(?:[_\-][a-z]+))+$/';

Lookahead & -behind are unneccessary in this case, and this keep it
simple.
Good point. It doesn't make sense to use assertions when you'll
capture
the matches anyway.
Somehow, i believe Rik's solution, gave me problems ...

'/^(?:[a-z0-9]|[a-z0-9][_\-][a-z0-9])+$/'; gave problems.
'/^(?:[a-z0-9]|(?<=[a-z0-9])[-_](?=[a-z0-9]))+$/' didn't.

An example string that gave problems is:
really_a_made_up_string


Ah, forgot that in [a-z0-9][_\-][a-z0-9] the character on the right is
already matched, so it won't work as a start for the second _ in _a_....

This one should still be working though:
$regex ='/^(?:[a-z0-9]+(?:[_\-][a-z0-9]+)*)$/';

Grtz,
--
Rik Wasmus


.

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