Caching Accessor Methods

Calling via AUTOLOAD incurs overhead
Aliasing also incurs some overhead
We can avoid almost all overhead and win the tradeoff:

        sub AUTOLOAD {

          # ... as before; set up $method ...

          my $code = q{
            sub {
              my ($self) = @_;
              my $val = $self->{METHODNAME};
              $self->{METHODNAME} = shift if @_;
              $val;
            }
          };

          $code =~ s/METHODNAME/$method/g;

          *$AUTOLOAD = eval $code;    
          goto &$AUTOLOAD;
        }

The first time, it constructs and compiles the code for the method
Second time, the method is called directly with no AUTOLOAD
No overhead!
There's that magic glob again.