I am currently working on a module for combinatorics and manipulation of words in sage (which is much more powerful than what is already there). You can find our current code at http://sage-words.googlecode.com/ if you are interested.
We started out using as little as possible from the Sage library and then realized this was a bad idea and went the opposite direction. In this process I have encountered a problem with the Element class. I have a class which represents the set of words over an alphabet (but is not a Monoïd since it also contains infinite words) and another class which represents a word. These classes have a natural Parent/Element relationship and I tried to use these classes from Sage as superclasses. But I am encountering various problems due to the implicit assumption that the Elements are always sort of numeric. As an example Element.__nonzero__() tries to call the parent with 0 to compare against the 0 element. But in my case it does not makes sense to create a word from that. So I am stuck. We already have a working parent/element relationship, but since it is not the Sage one it does not participate in coercions and we can't use Sage morphisms. Should I file a bug about this, override methods that make these assumptions with sensible stuff for my case or add ugly hacks to allow _parent(0). Arnaud --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---