In article <[EMAIL PROTECTED]>, [EMAIL PROTECTED] (Bengt Richter) wrote:
> On Mon, 14 Mar 2005 23:44:46 -0700, Steven Bethard <[EMAIL PROTECTED]> > wrote: > > >Ron Garret wrote: > >> What I'm really trying to do is to create enumerated types such that if: > >> > >> e1 = enum(lst) and v = e1(x) > >> > >> then > >> > >> (x in lst) and (e1[v] == x) > > > >Use a class with __call__ and __getitem__: > > > >py> class enum(object): > >... def __init__(self, vals): > >... self.vals = vals > >... def __call__(self, val): > >... return self.vals.index(val) > >... def __getitem__(self, index): > >... return self.vals[index] > >... > >py> lst = 'abcd' > >py> x = 'b' > >py> e1 = enum(lst) > >py> v = e1(x) > >py> (x in lst) and (e1[v] == x) > >True > > For that, why not just > > class enum(list): > def __call__(self, val): return self.index(val) Because I forgot to mention that I also want type(v)==e1. (Enum is a small part of a static typing system for automatically generating database schema from data models.) rg -- http://mail.python.org/mailman/listinfo/python-list
