Hi Trevor, Right...I remember coming across this problem before. Since I know this class is for internal use (simply to index a basis), we can override __call__() instead of _element_constructor_() as we do not need to invoke the coercion framework (and we want this to be fast). This is what the subsets code does too.
Best, Travis On Tuesday, June 21, 2022 at 1:20:07 AM UTC+9 Trevor Karn wrote: > Hi all, > > I am trying to implement a Parent in the category of > FiniteEnumeratedSets().Facade(). My hope was to have the finite enumerated > sets be represented by `Bitset > <https://doc.sagemath.org/html/en/reference/data_structures/sage/data_structures/bitset.html#sage.data_structures.bitset.Bitset>`s. > > Upon testing, I get the error: TypeError: Cannot convert > sage.data_structures.bitset.Bitset to sage.structure.element.Element. I > also get the same error when I set facade=True in the Parent.__init__ call. > I think this behavior makes sense because (as I understand it) the facade > elements should be elements of *some* parent, just not the parent `self`. > On the other hand, Bitsets are not an element of any parent. > > Does anyone have advice on how to proceed? I can think of a few options: > > - Make Bitsets an Element. This doesn't seem desirable because Bitsets is > Cythonized, and as I understand it, Cython doesn't play nice with the > Parent/Element framework (please correct me if I misunderstand). > > - Make an Element class for my Parent which inherits from both element and > Bitset. This doesn't seem desirable because I want my parent to be in > FiniteEnumeratedSets().Facade(). > > I don't like either of those options, does anyone have suggestions on what > else I could do? > > Thanks so much! > > -Trevor > > > -- 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 view this discussion on the web visit https://groups.google.com/d/msgid/sage-devel/5646a2cb-22d5-43bb-bcbd-b92b0119fb00n%40googlegroups.com.
