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Omission in R^3.5 LETREC description?

    Date: Mon, 23 May 88  23:46:05 EDT
    From: Ziggy at VX
    To:   jar at ai
    Re:   Omission in R^3.5 LETREC description?

     Shouldn't the caveat: [p.10 or R^3.5]

     "...without referring to the value of any <variable>."


     "...without referring to the value or location of any <variable>."

     Specifically, isn't the following a screw case:

     (LETREC ((wanna-be-a-doctor    'DOCTOR)
	      (imagine-my-surprise! (BEGIN (SET! wanna-be-a-doctor 'NURSE)
	wanna-be-a-doctor)  ==>  NURSE

    One could reasonably assume, based on the English description (and
    desugaring on page 36) that the RHSs will each be evaluated then
    their results will be stored thus the above should yield DOCTOR.
    Note that the value of WANNA-BE-A-DOCTOR is not referred to, but the
    location to which it is bound IS.

Yuck.  I'm not sure we want to be quite this anal about it, and I'm a
little worried about formal description and implementation of the kind
of error checking you suggest.  It would require making LETREC a
primitive, rather than derived, expression type, I think.  I'm cc'ing
rrrs-authors to see whether anyone else has thought about this and has