On Apr 22, 2009, at 5:20 PM, Greg Ewing wrote: > Robert Bradshaw wrote: > >> You have to ignore the type-specific optimizations, because mylist >> (or a subclass thereof) might override the default behavior. > > That's somewhat tricky in Pyrex, because it makes its > optimisation decisions based on the static type of the > object. So if you pass your list subclass to something > declared as taking a list, the list optimisastions will > get done on it anyway. > > I'm not sure what's the best thing to do here -- only > do the optimisations for something declared as exactly > a list, or for any subclass of list.
In Cython we only allow None or exactly a list to be assigned to a cdef list variable, not subclass thereof. We discussed this when we introduced it, and I am still convinced it is the right thing to do, but perhaps this makes subclassing messier. - Robert _______________________________________________ Cython-dev mailing list [email protected] http://codespeak.net/mailman/listinfo/cython-dev
