PEP 354: Enumerations in Python

[Roy Smith]

A few random questions:

a = enum ('foo', 'bar', 'baz')
b = enum ('foo', 'bar', 'baz')

what's the value of the following:

a == b
a is b
a.foo == b.foo
a.foo is b.foo
len (a)
str (a)
repr (a)
hash (a)
type (a)

Can you make an enum from a sequence?

syllables = ['foo', 'bar', 'baz']
c = enum (syllables)

You imply that it works from "An enumerated type is created from a sequence 
of arguments to the type's constructor", but I suspect that's not what you 
intended.

BTW, I think this is a great proposal; enums are a badly needed part of the 
language.  There's been a number of threads recently where people called 
regex methods with flags (i.e. re.I) when integers were expected, with 
bizarre results.  Making the flags into an enum would solve the problem 
while retaining backwards compatibility.  You would just have to put in the 
re module something like:

flags = enum ('I', 'L', 'M', 'S', 'U', 'X')
I = flags.I
L = flags.L
M = flags.M
S = flags.S
U = flags.U
X = flags.X

then the methods which expect a flag can do:

if flag is not in re.flags:
   raise ValueError ("not a valid flag")

and the ones which expect an integer would (if nothing better), raise 
NotImplemented when they tried to use the value as an integer if you passed 
it a flag by mistake.