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Subject: Re: equals(), Sets, Maps, and degrees of equality
Date: Fri, 11 Nov 2011 15:19:49 -0800
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On 11/11/2011 2:22 PM, Lew wrote:
> Because you want to use 'Dog' to model 'Breed', and they aren't the same thing at all.


That's what I'm getting too form Andreas and Eric.  Breeds are discreet 
things that ought to be first class objects in a design like this. 
Modeling them as just String seems sub-optimal.  It's about as bad as 
modeling Zip codes as strings or ints.  You can, sure, but why not apply 
a type to it?  Zip codes have just enough structure and invariants that 
strings or ints are almost certainly too loosey-goosey.

It's taken me a little bit to understand what they've been talking about 
because the original design was straight forward and simple, but the 
original design is probably wrong too for anything besides a throw away 
example.


>>>> Sean Mitchell wrote:
>>>>> I may want to have a Set<Dog>, which holds only one Dog of each breed,

 >> On Nov 11, 10:27 am, Lew<lewb...@gmail.com>  wrote:
>>> This is terrible modeling.

 > On Friday, November 11, 2011 10:28:35 AM UTC-8, Sean Mitchell wrote:
>> Really. Why?

On 11/11/2011 2:22 PM, Lew wrote:
> Because you want to use 'Dog' to model 'Breed', and they aren't the same thing at all.