Perl is a programming language, just like C, only it is even weirder.

$ perl -e '$a=3; $b=++$a + $a++; print "$b\n";'
9
$ perl -e '$a=3; $b=++$a + ++$a; print "$b\n";'
10
$ perl -e '$a=3; $b=$a-- + $a++; print "$b\n";'
5
$ perl -e '$a=3; $b=--$a + ++$a; print "$b\n";'
6

My Bizarrotron just broke its indicator needle. Fascinating!