[plt-scheme] about letrec and continuation : which behavior is correct ? and why ?

From: Matthew Flatt (mflatt at cs.utah.edu)
Date: Wed Aug 20 22:18:44 EDT 2008

At Wed, 20 Aug 2008 19:05:23 -0700, Michael Vanier wrote:
> I wasn't aware that "letrec" was defined in terms of its let/set! 
> semantics (though I knew that it could be so defined).  I had always 
> assumed that it was a primitive.  To muddy the waters further, I believe 
> that R6RS says that internal defines are actually translated into 
> "letrec*", even though I don't know of any Scheme implementation that 
> actually supports "letrec*".

R6RS implementations provide `letrec*'.

FWIW, PLT Scheme's `letrec' corresponds to R6RS's `letrec*'.

> One other gripe: I've read in some places that PLT Scheme has about 12 
> fundamental special forms, but I can't find any documentation about 
> which forms they are.



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