Martin Baker <ax87...@martinb.com> writes: [...]
| I'll try to think of an example, say in Haskell one may write: | | class Monad m where | fmap :: (a -> b) -> m a -> m b | id :: a -> m a | mult :: m (m a) -> m a | | where 'm', 'a' and 'b' all stand for types, and we can loop these | types back on themselves to give a whole sequence of types. If its not | too confusing to give them SPAD type names a ListMonad may 'generate': | | a = NNI | m a = List NNI | m m a = List List NNI | m m m a = List List List NNI | ... | | This seems to me that a big essence of category theory, that is: | external structure (arrows, functors, endofuntors) is generating | internal structure (types) by a sort of closure operation. | | I am struggling to understand if or how this could be transposed into | SPAD. It is often overlooked that the Spad language had an influence (and not so small) on the design of Haskell type classes. -- Gaby ------------------------------------------------------------------------------ Get a FREE DOWNLOAD! and learn more about uberSVN rich system, user administration capabilities and model configuration. Take the hassle out of deploying and managing Subversion and the tools developers use with it. http://p.sf.net/sfu/wandisco-d2d-2 _______________________________________________ open-axiom-devel mailing list open-axiom-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/open-axiom-devel
