I agree, subject to changing "SageObject" in 1 to "Element and CategoryObject". David
On Sat, Feb 27, 2010 at 6:14 AM, Florent Hivert < florent.hiv...@univ-rouen.fr> wrote: > Hi Robert, > > >> In order to sanitize the behavior of objects, parents and elements in > >> sage, > >> I'm about to add some tests to the framework. I think they are all > >> reasonable > >> but I may be asking to much. Please comment about the following: > >> > >> 1 - Any SageObject must have an equality methods such that > >> self == self and self != None > >> > >> 2 - Element construction should be idempotent. More precisely, for any > >> element e within parent P, the equality P(e) == e must hold. > >> This is for example needed by the constructor of many Parent with a > >> base > >> ring, such as matrices. > > > > Elements of real interval fields don't satisfy the above two constraints > > (the notion of equality for intervals being that every element of the > first > > interval is equal to every element in the second). > > You get the point. As far as I understand a RIF only return True if the > interval are reduced to a single point. Is it right ? It would be better to > return a special value like Unknown than False. But that's another > question... > > Anyway, I'm strongly info favor of giving 1- and 2- a general rule with an > explicit exception for RIF. As I said, the test framework allows such > exceptions. Is there an agreement on > > * Making 1- and 2- below a general rule > > >> 1 - Any SageObject must have an equality methods such that > >> self == self and self != None > >> > >> 2 - Element construction should be idempotent. More precisely, for any > >> element e within parent P, the equality P(e) == e must hold. > > * Making explicit exception for particular cases such as RIF. > > Cheers, > > Florent > > > > -- > To post to this group, send an email to sage-devel@googlegroups.com > To unsubscribe from this group, send an email to > sage-devel+unsubscr...@googlegroups.com<sage-devel%2bunsubscr...@googlegroups.com> > For more options, visit this group at > http://groups.google.com/group/sage-devel > URL: http://www.sagemath.org > -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
