It looks like mine is more complete, with data inheritance, inclusion of external files (which allows explicit loading of functionality into selected objects), and the ability to delete fields or methods.
At least from the README; I haven't been able to get a copy of it from CPAN yet.
update: I finally found a copy; it's efficient but doesn't provide for inheritance or data fields; mine is much more complete. And just as fast, as far as I can tell. I also benchmarked against Class::Classless; my code is quite a bit faster (168x as fast for inherited subroutine calls, 20+ times as fast for field access!):
empty subroutine calls
Rate Classless SelfMethods Prototyped Object Pl
+ainOleData
Classless 4225/s -- -95% -99% -99%
+ -99%
SelfMethods 90540/s 2043% -- -84% -84%
+ -85%
Prototyped 577873/s 13578% 538% -- -1%
+ -2%
Object 582772/s 13694% 544% 1% --
+ -1%
PlainOleData 587346/s 13802% 549% 2% 1%
+ --
empty inherited subroutine calls
Rate Classless Prototyped Object
Classless 3370/s -- -99% -99%
Prototyped 568592/s 16772% -- -1%
Object 572334/s 16883% 1% --
field reading
Rate Classless SelfMethods Prototyped PlainOleD
+ata
Classless 3969/s -- -88% -95% -
+98%
SelfMethods 34115/s 760% -- -54% -
+84%
Prototyped 74488/s 1777% 118% -- -
+64%
PlainOleData 209199/s 5171% 513% 181%
+ --
field writing
Rate Classless SelfMethods Prototyped PlainOleD
+ata
Classless 3760/s -- -92% -96% -
+98%
SelfMethods 47737/s 1170% -- -44% -
+74%
Prototyped 85151/s 2165% 78% -- -
+54%
PlainOleData 184470/s 4806% 286% 117%
+ --
inherited field reading
Rate Classless Prototyped
Classless 3268/s -- -96%
Prototyped 73604/s 2152% --
inherited field writing
Rate Classless Prototyped
Classless 3231/s -- -96%
Prototyped 85301/s 2540% --
