Howdy! On 2013-10-18, Robert Bradshaw <rober...@math.washington.edu> wrote: > It's a little more subtle than that. The underlying restriction is > that one can't have multiple inheritance of classes whose C members > (including cdef methods) are incompatible.
A little remainder: There are cases of classes whose C members are considered to be *compatible* (e.g., sage.categories.maps.Map and sage.structure.element.ModuleElement or RingElement, I don't recall which), but when one creates a python class inheriting from both extension classes, then in fact the C members of the two bases may get confused. > On that note, I have been looking at exposing C function pointers at > runtime, which would avoid the Python calling overhead and allow > passing of primitive types without the need for compile-time > declarations or fixed layouts. I don't know the internals of GAP very well. But someone has told me that GAP chooses functions according to what it has discovered about a specific object (hence, it can change over time), and it does so with C speed. Is GAP's method similar to what you suggest here? >> - explore the cythonization of category methods In UniqueRepresentation, we have to use a Python class because it uses a metaclass, but in addition we inherit from an extension class, which provides equality test and hash with Cython speed. Now I wonder why you said "*explore* the cythonization". Wouldn't it be easily possible to proceed as with UniqueRepresentation, and create extension classes that are then mixed into the element and parent classes of the categories? Wouldn't this be the natural place to feed the *Element and the Cythoned Parent classes into the category framework? Modulo the incompatibility I mentioned above, of course. Best regards, Simon -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/groups/opt_out.
