2.4.3 Auto-Increment and Decrement
The auto-increment and auto-decrement operators in Perl work almost
identically to the corresponding operators in C, C++, or Java. Here are
few examples:
use strict;
my $abc = 5;
my $efg = $abc-- + 5; # $abc is now 4, but $efg is 10
my $hij = ++$efg - --$abc; # $efg is 11, $abc is 3, $hij is 8
