http://www.perlmonks.org?node_id=195907


in reply to Re^2: The High Price of Golf, and A Surprise
in thread The High Price of Golf, and A Surprise

perldoc perldelta, for 5.6.1 says the following about sort:

Simple sort() using { $a <=> $b } and the like are optimized

Many common sort() operations using a simple inlined block are now optimized for faster performance.

Mind you, I was under the impression that this optimisation occurred earlier, sometime back around the 5.004 to 5.005 timeframe. I'll have to go and look on some of my older machines.
print@_{sort keys %_},$/if%_=split//,'= & *a?b:e\f/h^h!j+n,o@o;r$s-t%t#u'