package Tie::ReverseScalar;

sub TIESCALAR {
    my $class = shift;
    return bless \$_[0] => $class;
}

sub FETCH {
    return reverse ${$_[0]};
}

sub STORE {
    ${$_[0]} = reverse $_[1];
}

sub DESTROY {
    undef ${$_[0]};
}

1;
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use Tie::ReverseScalar;
sub Reverse :lvalue { 
    my $x = @_ ? \$_[0] : \$_;
    tie $x, 'Tie::ReverseScalar', $$x; $x
}

$_ = 'foo';
chop Reverse;
print;

__END__
oo
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Update: oops, I had written that this output "fo" (which wouldn't have been interesting at all), but it actually outputs "oo" (which is what makes it cool). Thanks, BrowserUK, for pointing out the typo.

------------
:Wq
Not an editor command: Wq
[download]

Colour me confused but isn't:

$_ = 'foo';
chop Reverse;
print;

__END__
fo
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a complicated way of doing?:

$_ = 'foo'; chop; print;

fo
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---

Examine what is said, not who speaks.

"Efficiency is intelligent laziness." -David Dunham
"Think for yourself!" - Abigail
"Memory, processor, disk in that order on the hardware side. Algorithm, algorithm, algorithm on the code side." - tachyon

Yes you can. You don't even need to go as far as you're thinking about.

BEGIN {
    sub funky_reverse : lvalue {}
    *CORE::GLOBAL::reverse = \&funky_reverse;
}
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It doesn't help you, though. You really want to return an alias (or a list thereof), not any old lvalue(s). And that's not something you can do in vanilla Perl. You need something like Data::Alias.