Hi William On 19 Dez., 22:43, William Stein <[email protected]> wrote: > But I'm personally OK with loosing this feature. The feature we're > loosing though is this: objects of a category have to support weak > references. > > Is that feature OK to loose? I can't think of a reason we need that feature.
We certainly do not loose that feature - because that feature simply does not exist. Namely, any element is considered to be an object in some category, such as sage: 1.category() Category of elements of Integer Ring However, sage.structure.element.Element does not support weak references, such as sage: weakref.ref(1) --------------------------------------------------------------------------- TypeError Traceback (most recent call last) /home/simon/SAGE/sage-4.8.alpha3/<ipython console> in <module>() TypeError: cannot create weak reference to 'sage.rings.integer.Integer' object So, there currently *are* objects of some strange category that do not support weak references - which is why these 3 times 2 doctests fail when using a weak cache for homsets. Cheers, Simon -- To post to this group, send an email to [email protected] To unsubscribe from this group, send an email to [email protected] For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
