[plt-scheme] How is letrec different from letrec* in its use?

From: Alex Shinn (alexshinn at gmail.com)
Date: Fri Feb 13 01:59:12 EST 2009

Shriram Krishnamurthi <sk at cs.brown.edu> writes:

> These threads (we had a recent flare-up about LOCAL, as
> some might recall) point to the worst thing about Old
> Scheme: not only did they leave the semantics undefined,
> they ALSO didn't have the courtesy to provide a reference
> compiler that actually produced unexpected output, thereby
> compounding confusion (resulting in unknown unknowns).

Where's the reference implementation that gets this right
for R6RS?  Neither plt-r6rs nor larceny signal an error.
Ikarus signals the wrong error, but doesn't signal an error
if you replace `+' with `cons'.


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