Re^2: How can I make a string unique (quicker than my approach at least)

[hippo]

my( $pre, $post ) = split m{(?<=>)};

Interesting - you have assumed that the <TAB> in the OP's data is literally those 5 characters whereas in my reading they were using this to indicate a single tab character. Doesn't matter really, but it would make the split regex simpler if it were a single tab.