Those are spec issues, not defects in my solution. There's no spec saying what happens if there's no overlap, so how is it wrong to return a string with a space in it? It's better than starting a game of nethack or deleting all the files on the user's disk.

The maximal overlap rule conflicts with the last-overlap rule. Doing maximal overlap is easier than what I posted (you remove the first capture group and substitute nothing in). And changing the + to a * ensures that the space gets removed, even if the overlap is empty. Does this conform to your understanding of the specs? 

$catted =~ s/(.*) (?=\1)//;

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In reply to Re^3: Merging Two Strings by Roy Johnson
in thread Merging Two Strings by monkfan

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