On Mon, Dec 27, 2010 at 11:14 AM, Justin C. Walker <jus...@mac.com> wrote: > Thanks for the reply. > > On Dec 26, 2010, at 03:17 , Volker Braun wrote: > >> Python has no "const". You can always manually change the innards of your >> class. The set_immutable() is just implemented by hand. > > Tuples are "really" immutable, correct? Is this possible because the tuple > is an internal data type?
Well, you can change them from Cython :). It's because they're implemented in C, and (by design) no Python-level "hooks" are created to mutate them from Python. >> One could override __setattr__() to catch assignments to existing >> attributes, but I think that is not done anywhere in Sage. > > Are 'attributes' the same as (or do they include) instance variables? Yes, attributes include variables, methodes, etc. When you do x.a = var Then x.__gsetattr(x, a, var) gets called, which by default just updates the dictionary of attributes of x. - Robert -- 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
