$var = "aaa";
++$var; # or: $var++
print "Var is: $var\n";
__END__
Var is: aab
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Ah, the magic of Perl.

Update: D'oh. davorg++ for speed. ;-)

Update2: Oh, and just to make sure that it's clear: ($var = "az")++; $var == "ba";

bbfu
Seasons don't fear The Reaper.
Nor do the wind, the sun, and the rain.
We can be like they are.