[Newbies] reimplementing #= and #hash

[Oscar Nierstrasz]

Hi Ching,

#hash should be reimplemented to make sure that objects considered to  
be equal will end up in the same hash bucket.

The usual trick is to take a bitXor of the hashes of the instance  
variables:

PoolQueue>>hash
	^ member hash bitXor: processor hash

Hope that helps.
Oscar

On Sep 23, 2007, at 9:52, Ching de la Serna wrote:

> Hi List,
>
> I have a Class PoolQueue which has instvars 'member' and  
> 'processor'. I find that an instance of PoolQueue when placed in an  
> OrderedCollection can no longer be considered equal. I suppose I  
> have to reimplement #= and #hash to allow PoolQueue instances to be  
> compared.
>
> My problem: how do I implement #hash? Or stated another way, what  
> does #hash accomplish?
>
> Thanks in advance.
>
> Ching.
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