From: brangdon@... (Dave Harris)
Date: 2001-10-27T04:33:52+09:00
Subject: [ruby-talk:23498] Re: Overriding #== [numeric operators; hashing and comparison; binary selector

pulsar@qks.com (David Simmons) wrote (abridged):
> I suggest, taking it from SmallScript, that object-equivalence #(==~) is
> what you are looking for.

I read that name as saying, "approximately identical to", which is not 
what I am looking for. I want "identical to", in the same way that #= 
means "equal to". In my view both notions make sense at base-level (ie 
non-MOP level).

#== is a natural name for the function I want, by analogy with #=. If 
there is to be some MOP test, perhaps it should be given the strange name, 
perhaps #basicIdentical:.


>        hash/compare op correspondence
> ---    ------------------------------
> MOP    #basicHash (corresponding to [MOP] #==) [aliased as #identHash]
> USER   #identEquivHash (corresponding to #==~) [not in QKS Smalltalk]
> USER   #hash (corresponding to #= and #==~)
> USER   #equivHash (corresponding to #=~)

How can #==~ correspond to both #hash and #identEquivHash?

  Dave Harris, Nottingham, UK | "Weave a circle round him thrice,
      brangdon@cix.co.uk      |   And close your eyes with holy dread,
                              |  For he on honey dew hath fed
 http://www.bhresearch.co.uk/ |   And drunk the milk of Paradise."