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Re: how expressive are they?



Guy Steele - Sun Microsystems Labs <Guy.Steele@sun.com> writes:

>    Date: Fri, 22 Nov 2002 14:44:59 -0800 (PST)
>    From: Avi Bryant <avi@beta4.com>
>    To: Guy Steele - Sun Microsystems Labs <Guy.Steele@sun.com>
>    cc: tlb@anybots.com, <ll1-discuss@ai.mit.edu>
>    Subject: how expressive are they?
>    ...
>    
>    Smalltalk doesn't need primitives or macros:
>    ...
>    
>    x and: [y] and: [z]
>    x ifTrue: [y] ifFalse: [z]
>    
> And see how much wordier these are than (AND x y z) and (IF x y z).

Note too that he's not comparing apples and apples. In a lisp
language something is true if it isn't nil. Looking at my handy dandy
Smalltalk image, I find that Object#and:, Object#ifTrue: and all the
other handy dandy 'query + block' methods, with the exception of
'Object#ifNotNil:' don't actually exist. So, to duplicate the lispish
semantics that becomes

   x ifNotNil: [y] ifNotNil: [z].

   x ifNotNil: [z] ifNil: [y].

Which are, admittedly more specific about what's going on, but aren't
exactly paragons of compactly expressive power.

I do wonder if this argument isn't getting a bit silly though...

-- 
Piers

   "It is a truth universally acknowledged that a language in
    possession of a rich syntax must be in need of a rewrite."
         -- Jane Austen?