Question

I have two cases to match: either

# ... ([0-9]+,[0-9]+) € ... #

or

# ... (--) ... #

Now,

# ... (?:(--)|([0-9]+,[0-9]+) €) ... #

isn’t working, it says

Unknown modifier '(' ...

I’m using preg_match_all() on PHP 5.3

Those above are NOT the full expressions, just extracts!

Answer 1

Your regular expression works without errors:

 $p = "/(?:(--)|([0-9]+,[0-9]+) €)/";
 echo preg_match($p, "--")."\n";                // outputs 1
 echo preg_match($p, "nomatch")."\n";           // outputs 0

Please post your PHP code so we can identigy the problem