Have you ever used them? The character classes you use will any of the characters in :epru and :elorw respectively. POSIX classes are used like this: 
/^(\d+)([[:upper:]][[:lower:]]*)([[:upper:]][[:lower:]]*)/;

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Makeshifts last the longest.

In reply to Re^2: Newbie RegEX question (posix charclass syntax) by Aristotle
in thread Newbie RegEX question by jmaya

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