Antoon Pardon wrote:
Op 2004-12-15, Roel Schroeven schreef <[EMAIL PROTECTED]>:
Antoon Pardon wrote:
Op 2004-12-15, Fredrik Lundh schreef <[EMAIL PROTECTED]>:
sorry, but I don't understand your reply at all. are you saying that
dictionaries
could support mutable keys (e.g lists) by making a copy of the key? how would
such a dictionary pick up changes to the original key object? (I'm talking
about
the key stored in the dictionary, not the key you're using to look things up).
You want to mutate a key that is within a dictionary?
No, we don't want to mutate it; as far as I know, that is exactly the
reason why dictionaries don't support mutable keys.
And I think that is a stupid reason. There are enough other situations
were people work with mutable objects but don't wish to mutate specific
objects. Like objects in a sorted sequence you want to keep that way
or objects in a heapqueue etc.
Demanding that users of dictioanaries somehow turn their mutable objects
into tuples when used as a key and back again when you retrieve the keys
and need the object can IMO ibe a bigger support nightmare than the
possibility that code mutates a key in a dictionary.
So provide your objects with a __hash__ method, and you can use them as
dictionary keys.
Sheesh, learn Python already. What a troll. [Plonk]
regards
Steve
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