Inspiration whacked me in the head yesterday, and I realized that it was pretty easy to take an arbitrary hash reference and turn it into an object, so that instead of writing $hash->{key} I can just write $hash->key, saving two characters and giving me protection from typos. Enter Util::H2O:

use Util::H2O;
my $hash = h2o { foo => "bar", x => "y" }, qw/ more keys /;
print $hash->foo, "\n";  # prints "bar"
$hash->x("z");  # setter
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Deeply nested structures can be converted too...

my $struct = { hello => { perl => { world => "yay" } } };
h2o -recurse, $struct;
print $struct->hello->perl->world, "\n";  # prints "yay"
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The function blesses its hashref argument into a new package, and returns that hashref as well. The hashrefs otherwise remain the same as before, so you can still use $hash->{key} and so on if you like. The newly created package is cleaned up by default when the object is destroyed (configurable). These objects are of course a bit less performant than a regular hashref, but this wasn't intended for high-performance applications.

Update: As of the freshly-released v0.06, the h2o function also locks the hash's keyset by default, to prevent typos when using the hash like a regular hashref. This can be disabled with the -lock=>0 option. /Update

I quickly realized I could do more with this, like add methods to these objects:

my $obj = h2o -meth, {
    one => 123, two => 456,
    sum => sub {
        my $self = shift;
        return $self->one + $self->two;
    } };
print $obj->sum, "\n";  # prints "579"
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And I could even make it easy to create classes; the -new option generates a constructor:

h2o -class=>'Point', -new, -meth, {
        angle => sub { my $self = shift; atan2($self->y, $self->x) },
    }, qw/ x y /;
my $one = Point->new(x=>1, y=>2);
my $two = Point->new(x=>3, y=>4);
$two->y(5);
printf "%.4f\n", $two->angle;  # prints 1.0304
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Yes, I realize that might be taking it a little bit too far, but it was easy to implement - plus, I figured this could possibly be useful for whipping up mock objects in tests. And yes, I'm aware similar tools exist ;-)