Re: Proposed modifications to R3RS

[Jeff Dalton <jeff%aiva.edinburgh.ac.uk@NSS.Cs.Ucl.AC.UK>]

> b)  Overspecification should be avoided as it artificially
>     prohibits reasonable implementations.

> 3)  I believe that AND is overspecified as it states that "[...]
>     If all the expressions evaluate to true values, the value of
>     the last expression is returned."

>     (A similar change should be made to OR.)

Your complaint about AND is that it returns the value of the last form
instead of simply true or false.  But calling that "overspecification"
is just another way of saying it should return simply true or false,
and so it is not an argument for returning true or false.

I guess what I'm trying to say is that it depends on what you want AND
and OR to be.  Only if you want logical operations and no more are
they overspecified.

I don't much mind the change in AND.  After all, only the last
expression can return anything other than #f.  With OR, on the other
hand, it's useful to know which true value was obtained. 

Jeff Dalton,                      JANET: J.Dalton@uk.ac.ed             
AI Applications Institute,        ARPA:  J.Dalton%uk.ac.ed@nss.cs.ucl.ac.uk
Edinburgh University.             UUCP:  ...!ukc!ed.ac.uk!J.Dalton