It's been ages since I last posted here, but here goes.

Your first statement is false. This egrep doesn't make sure that all characters occur, so it makes sense that it seems to be harder in perl. Egrep tries to match either of the characters you specified, and spits out only the parts that match, because of the -o: 
echo 1b22a3d3 | egrep -o 'a|b|c|d'
b
a
d

[download]

All Camels are equal, but some Camels are more equal than others.

In reply to Re: How to replace greedy alternation? by jink
in thread How to replace greedy alternation? by adamcrussell

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