Hi Eric, On 2015-11-05, Eric Gourgoulhon <egourgoul...@gmail.com> wrote: > Le jeudi 5 novembre 2015 10:32:29 UTC+1, Simon King a =C3=A9crit : > Yes this is precisely what we had in mind: to delegate the mathematical > comparison of manifolds to a specific method is_homeomorphic, which > in most case will answer "I cannot answer" (cf. comments 39 and 40 in=20 > the ticket).=20 > Then if we have both CachedRepresentation and equality-by-identity, then > we have UniqueRepresentation, don't we?
*Will* you have equality-by-identity? Certainly, if "A is B" then "A==B" will be True. Actually I am not sure if A.__eq__ would be invoked at all if you compare to identical objects (i.e., I don't know what Python does). But if A is not B and ask "A==B", then you could say that you will do SOME effort to test for equality in the sense of homeomorphism. I don't know if you want to do some heuristics here. Anyway, if you think that equality-by-identity is the right way of comparison in your applications, then UniqueRepresentation might be the correct tool. 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/d/optout.