Re: [Chicken-users] Syntax of case expressions

[Matt Gushee]

Ivan Raikov wrote:

>   Remember that in Scheme, (define foo 'a) is a shortcut for 
> (define (define foo (quote a))) -- quote is a special form, and not
> a part of the literal. So you in your case statement you are not
> matching the symbol a, you are actually matching the symbol 'a (the
> apostrophe is treated as a literal in the case statement). Your first
> example should actually be: 
>
> (case foo
>   ((a) 1)
>   (else 2))

Wait a minute, though. I understand now why

  (('a) ...)

didn't match, but how is it that

  ('a ...)

isn't a syntax error? Is it because 'a expands to (quote a), and is thus 
treated by case as a list of the symbols quote and a? And if so, is that 
correct behavior? After all,

csi> (pair? 'a)
#f

(as I expected).

--
Matt Gushee
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