In list context, returns a list value consisting of the elements
of LIST in the opposite order. In scalar context, concatenates the
elements of LIST and returns a string value with all characters
in the opposite order.
print reverse <>; # line tac, last line first
undef $/; # for efficiency of <>
print scalar reverse <>; # character tac, last line tsrif
This operator is also handy for inverting a hash, although there are some
caveats. If a value is duplicated in the original hash, only one of those
can be represented as a key in the inverted hash. Also, this has to
unwind one hash and build a whole new one, which may take some time
on a large hash, such as from a DBM file.
%by_name = reverse %by_address; # Invert the hash
Take our 
