Hi Volker, On 2013-02-14, Volker Braun <vbraun.n...@gmail.com> wrote: > ------=_Part_664_5536941.1360842751143 > Content-Type: text/plain; charset=ISO-8859-1 > > On Thursday, February 14, 2013 6:43:32 AM UTC, Simon King wrote: > >> If one implements a new parent P and "forgets" to override >> sage.structure.parent_gens.ParentWithGens.gen, and then calls P.gen(), >> one will usually see a very disturbing error. > > > The solution is to not derive from old-style ParentWithGens and/or its base > class ParentWithBase. > > cdef class ParentWithBase(parent_old.Parent): > """ > This class is being deprecated, see parent.Parent for the new model. > """
Haha. sage: Ring.mro() [<type 'sage.rings.ring.Ring'>, <type 'sage.structure.parent_gens.ParentWithGens'>, <type 'sage.structure.parent_base.ParentWithBase'>, <type 'sage.structure.parent_old.Parent'>, <type 'sage.structure.parent.Parent'>, <type 'sage.structure.category_object.CategoryObject'>, <type 'sage.structure.sage_object.SageObject'>, <type 'object'>] I think it *is* recommended to use Ring, isn't it? 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?hl=en. For more options, visit https://groups.google.com/groups/opt_out.
