From: Sebastian Hungerecker <sepp2k@...>
Date: 2007-05-09T00:58:01+09:00
Subject: Re: Equality question

Brian Candler wrote:
> o1 = [:defuzz_configs, {"conf"=>"foo.txt"}]
> o2 = [:defuzz_configs, {"conf"=>"foo.txt"}]
> p o1 == o2              # prints true
> p o1.hash == o2.hash    # prints false ??             <<<<<<<<<<<

That's because the Hashs in o1 and o2 are two different objects.

>> hash={:bla=>:blubb}
=> {:bla=>:blubb}
>> a1=[:a,hash]
=> [:a, {:bla=>:blubb}]
>> a2=[:a,hash]
=> [:a, {:bla=>:blubb}]
>> a3=[:a,{:bla=>:blubb}]
=> [:a, {:bla=>:blubb}]
>> a1==a3
=> true
>> a1.hash==a3.hash
=> false
>> a1.hash==a2.hash
=> true
>> hash[:blu]=:blo
=> :blo
>> p a1,a2,a3
[:a, {:bla=>:blubb, :blu=>:blo}]
[:a, {:bla=>:blubb, :blu=>:blo}]
[:a, {:bla=>:blubb}]
=> nil
>> a1==a3
=> false
>> a1==a2
=> true


HTH,
Sebastian Hungerecker
-- 
Ist so, weil ist so
Bleibt so, weil war so