On Wed, Dec 05, 2012 at 11:47:25PM -0800, Travis Scrimshaw wrote: > Hey everyone, > What is the reason why facade=True is allowable by Parent? It seems > like we always want to pass in the parent(s) which our facade parent is > acting for.
See the documentation on top of sage.categories.facade_sets (also available by introspection on Sets().Facade). In many cases, the list of parents will be decided at the end of the construction of the parent. Think parents with several representations like Sym or NCSF. And in a few cases, we just can't know which parents this will be a facade for. Or there could be infinitely many of them (think Partitions() that could possibly be a facade for all Partitions(n)). Vincent: the behavior described in the second example on the ticket is what it should be. The parent should override facade_for if it uses facade=True. On the other hand, if you find it useful, you may change the default implementation of facade_for to return a more meaningful example and/or add appropriate cross references in the documentation. For the first example: probably it's category.join that should be improved, but that will do for now. Cheers, Nicolas -- Nicolas M. ThiƩry "Isil" <nthi...@users.sf.net> http://Nicolas.Thiery.name/ -- You received this message because you are subscribed to the Google Groups "sage-combinat-devel" group. To post to this group, send email to sage-combinat-devel@googlegroups.com. To unsubscribe from this group, send email to sage-combinat-devel+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sage-combinat-devel?hl=en.