Warning preg_replace() Unknown modifier

[evident]

Primesc eroarea :Warning: preg_replace(): Unknown modifier '(' in
Linia respectiva:

Cod: Selectaţi tot

$text = preg_replace('([[:space:]()[{}])(www.[-a-zA-Z0-9@:%_\+.~#?&//=]+)',
'\\1<a href="http://\\2" target="_blank" rel="nofollow">\\2</a>', $text);
 

Salut
Codul RegExp se adauga intre 2 perechi de caractere, in general: "/.../" . Incearca asa:

Cod: Selectaţi tot

$text = preg_replace('/([[:space:]()[{}])(www.[\-a-z0-9@\:%_\+\.~#\?&\/=]+)/i',
'\\1<a href="http://\\2" target="_blank" rel="nofollow">\\2</a>', $text);