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Re: [Paul Graham <paulgraham@yahoo.com>] Re: What is alightweight language

At 10:17 AM -0500 12/14/01, jmarshall@mak.com wrote:
>There is no need for the escape continuation.
>(define (andmap fn list)
>   (or (and (pair? list)
>            (fn (car list))
>            (andmap fn (cdr list)))
>       (null? list)
>       (error "Improper list.")))
>I don't mean this as a nitpick.  I find it extremely rare that I need
>to use call-with-current-continuation because CPS doesn't cut it.

Well, I agree that I picked a dreadful example; no context is built 
up.  If I understand you correctly, you're suggesting either

a) a global CPS rewrite performed by you, the author or all your code, or
b) a local CPS rewrite of the kind that you demonstrate above.

If the former, I don't see how you can build large systems this way. 
If the latter, your uses of call/cc have shrunk to being able to 
escape from a recursive procedure which calls only leaf procedures. 
That is, you don't have the ability to 'abort' parts of the 
evaluation context which you didn't create.

john clements