[Python-Dev] PEP 351, the freeze protocol

[Christopher Armstrong]

On 10/24/05, Josiah Carlson <jcarlson at uci.edu> wrote:
> "Should dicts and sets automatically freeze their mutable keys?"
>
> Dictionaries don't have mutable keys,

Since when?

class Foo:
    def __init__(self):
        self.x = 1

f = Foo()
d = {f: 1}
f.x = 2

Maybe you meant something else? I can't think of any way in which
"dictionaries don't have mutable keys" is true. The only rule about
dictionary keys that I know of is that they need to be hashable and
need to be comparable with the equality operator.

--
  Twisted   |  Christopher Armstrong: International Man of Twistery
   Radix    |    -- http://radix.twistedmatrix.com
            |  Release Manager, Twisted Project
  \\\V///   |    -- http://twistedmatrix.com
   |o O|    |
w----v----w-+