Dear all, This is a proposal to implement a new operation somewhere in our coercion model: intersection of parents. The motivation is to enhance
1. comparison: x == y would work as expected when x and y belongs to the intersection of their parents (see [#4621] for a use case) 2. conversion: P(x) would work when the intersection of P and the parent of x contains x. By default, the intersection of two parents A and B would be None. Otherwise it would return a parent that has an injective coercion in both A and B with the requirement that intersection(A, B) is the same thing as intersection(B, A). Does it make sense? [#4621] https://trac.sagemath.org/ticket/4621 Best Vincent -- 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/d6103902-9dcf-b6b2-bd57-b79514c6bffa%40gmail.com.
