I come seeking your insights and wisdom. I "understand" the following example but I can't "comprehend" it (or vise-versa)... 
$_='aaab';
print "Matched 1=>$_\n" if /^[a]{2,}(?![b])+/;
print "LastMatch1:$&\n";

print "Matched 2=>$_\n" if /^[a]{2,}/;
print "LastMatch2:$&\n";

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I expected (hoped) that the first RE would fail - but it does not. It seems the negative lookahead causes a "lazy" match on the 1st pattern. That is, $& is set to 'aa' as if it were non-greedy. If I change the {2,} quantifier to {3,} the pattern works as I expect. That is, the pattern match fails. If I change the pattern to {2,3} is behaves the same as {2,}.

The second RE (without the lookahead) behaves greedily as expected setting $& to 'aaa'.

Your insights will be greatly appreciated.

In reply to Greedy match and zero-width negative lookahead assertion by jeffatrobertsdotnet

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