Hi,
I think it's indeed a good feature to discuss for 2.0.
I've been working on this too and had quite reasonable performance
when using a hash function that avoids collision.
The simplest implementation consists in storing array of [key, value]
tuples indexed by `key.toString()` in a vanilla object.
i.e. :
hash.set(true, value1);
hash.set("true", value2);
is stored as:
{ "true": [ [true, value1], ["true", value2] ] }
Custom classes should override their `toString` method to be
efficiently stored in such a structure, otherwise fetching a value
would be as slow as a `Array#find` call.
Having real hashes allows to implement sets too.
Best,
Samuel.
On 10 sept. 2009, at 22:46, T.J. Crowder wrote:
>
> Hi James,
>
> You're right, Hash does indeed rely on underlying JavaScript vanilla
> objects, which can only use strings as keys.
>
> Supporting using objects as keys would be a complete rewrite, and a
> fairly inefficient one in terms of runtime performance (I did it once,
> and abandoned it as not worthwhile). I'm not aware of any plans to do
> so. I suspect you'd be better off (from a performance standpoint)
> building toString / fromString support into your keys.
>
> FWIW,
> --
> T.J. Crowder
> tj / crowder software / com
> www.crowdersoftware.com
>
>
> On Sep 10, 7:07 pm, James Aimonetti <james.aimone...@gmail.com> wrote:
>> Core,
>>
>> Wanted to ask about why Hash doesn't support Objects as keys? I
>> believe
>> it relies on Javascript using the toString on the object to set the
>> key's value, rather than a true hash.
>>
>> var key1 = new Object();
>> var key2 = new Object();
>> var h = $H();
>> h.set(key1, "First");
>> h.set(key2, "Second");
>> h.get(key1) // -> Second
>>
>> Is there any plan to support true object-as-key ability? I couldn't
>> find
>> discussion on the topic searching the group.
>>
>> --
>> James Aimonetti
>> mobile: 314.809.6307
>> work: 540.459.2220
>> email: james.aimone...@gmail.com
>> website:http://jamesaimonetti.com
> >
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