`frozenset` and `set` make a counterexample:
>>> frozenset({1}) == {1}
True
On 02.05.20 22:36, Guido van Rossum wrote:
It does look like that would violate a basic property of `==` -- if
two values compare equal, they should be equally usable as dict keys.
I can't think of any counterexamples.
On Sat, May 2, 2020 at 1:33 PM Alex Hall <[email protected]
<mailto:[email protected]>> wrote:
On Sat, May 2, 2020 at 9:51 PM Serhiy Storchaka
<[email protected] <mailto:[email protected]>> wrote:
02.05.20 21:34, Ahmed Amr пише:
> I see there are ways to compare them item-wise, I'm
suggesting to bake
> that functionality inside the core implementation of such
indexed
> structures.
> Also those solutions are direct with tuples and lists, but
it wouldn't
> be as direct with arrays-lists/tuples comparisons for example.
If make `(1, 2, 3) == [1, 2, 3]` we would need to make
`hash((1, 2, 3))
== hash([1, 2, 3])`.
Would we? Is the contract `x == y => hash(x) == hash(y)` still
required if hash(y) is an error? What situation involving dicts
could lead to a bug if `(1, 2, 3) == [1, 2, 3]` but `hash((1, 2,
3))` is defined and `hash([1, 2, 3])` isn't?
The closest example I can think of is that you might think you can
do `{(1, 2, 3): 4}[[1, 2, 3]]`, but once you get `TypeError:
unhashable type: 'list'` it'd be easy to fix.
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