nil or #nil?
iamtv at hotmail.com
Tue Aug 25 23:45:58 UTC 1998
you people are pathetically geeky. Get your heads out of your pocket
protectors and get a life.
>From squeak-request at cs.uiuc.edu Tue Aug 25 16:25:26 1998
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>Date: Tue, 25 Aug 1998 18:19:19 -0500
>From: Dwight Hughes <dwighth at ipa.net>
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>To: squeak at cs.uiuc.edu
>Subject: Re: nil or #nil?
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>Dana Anthony wrote:
>> Dwight Hughes wrote:
>> > In this light, nil, true, and false are literals - but so are #nil,
>> > #true, and #false -- the problem right now is that nil ~~ #nil,
>> > #true, and false ~~ #false, which is a bit counterintuitive. Would
>> > outrage anyone to consider nil, true and false to be syntactic
>> > #nil, #true, and #false?
>> > -- Dwight
>> You bet people would be outraged.
>> Mainly because of a simple fact: #nil, #true, and #false are
>> of Symbol.
>> nil is an instance of UndefinedObject; true is of True and false of
>Well, I consider nil, true, and false to all be symbols -- in the
>generic sense -- and consider the schizm between them and instances of
>Symbol to be an design artifact forced upon Dan and crew to compensate
>for the single inheritance class structure and the limiting of method
>dispatch to the class of the receiver (instead of the receiver itself).
>So Dan waved his keyboard and said: "Let there be true and false and
>nil, and let each take unto itself a class and a place in the
>by which each shall be known to all." I understand your objections
>within the present Squeak/Smalltalk design, but I also find that having
>#nil, #true, and #false be meaningless symbols with no correspondence
>nil, true, and false to be rather ugly.
>> How can a symbol be == to an undefinedObject or a boolean? It
>That depends on how badly I want to win this debate ;-).
>> That's just not object oriented :) :)
>Ever hear of multiple inheritance? A dandy concept for situations like
>this (and for diverting attention from the topic at hand). (For those
>interested in such things, "closure based" multiple inheritance (as
>implemented in Idol - an object-oriented variant of Icon) is worth
>checking out: http://www.cs.utsa.edu/research/idol/closure.ps.)
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