My apologies, the code I posted was not "straight from the
Llama's mouth" and I should be more careful in using
that phrase. The code which I was pondering is on page
55 of the 2nd edition of the Llama and reads as follows:

@y = sort(@y);

What caught my mind is that Perl makes a point of not having one
repeat variables on both sides of an = and
sorting an array while maintaining its name is the opposite.
With humble contrition,
jg