-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On Apr 24, 2008, at 11:40 AM, Martin Vales wrote: > Hi: > > I have always had a doubt about OOP. > Usually we have a parent and several child, but what happen if we need > the inverse system. for example DBI/DBD APIs.?? Actually, thats quite a common problem of thought, because inheritance is often considered as _the_ problem solver in OOP. But that is not the case. I for my part seldomly inherit. The core feature of OOP is composition. So even without modules, you could just implement a class that has a certain set of features and hands everything else to a class that has a concrete implementation for that task (delegation, btw. ;) ). Depending on the language, this can get large because of the vast amount of boilerplate code you have to write for the delegating methods, but in Ruby, this is a simple task. Regards, Florian Gilcher -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.8 (Darwin) iEYEARECAAYFAkgRHZ8ACgkQJA/zY0IIRZbPZgCgp/Vx54NYWH6PppPXRENXic3s OwEAn2SFwl0BnIJsu+fvc4+RUBlUGbn/ =tD69 -----END PGP SIGNATURE-----