[r6rs-discuss] [Formal] Disallow redefinitions macros/variables

[Abdulaziz Ghuloum]

On Mar 27, 2007, at 8:24 PM, William D Clinger wrote:

> (Proving that the third semantics is distinct from
> the other two is left as an exercise for readers
> who wish to understand a dark corner of Scheme.)

Come on!  The dark corner is what gives us countless
hours of fun with Scheme puzzles and mind benders.

Here is one for the reader:

Is the following a valid transformation in general:
(list E1 E2)     and     (cons E1 (cons E2 '()))
Assume the usual meaning of cons, list, and quote
and arbitrary Scheme expressions E1 and E2.

Aziz,,,