[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Scheme-reports] [scheme-reports-wg1] Erratum for letrec* definition



Alex Shinn scripsit:

> Using letrec as though it were letrec* is indeed a bug.  Specifically,
> it "is an error", which means implementations are free to handle this
> situation however they want, including raising an exception or simply
> treating it as letrec*.

Yes, that's true (though not true in R6RS, where sequential dependency in
letrec must signal an error).  Besides the R6RS implementations, only MIT,
Scheme48/scsh, SigScheme, and TinyScheme do not handle letrec as letrec*,
though SISC prints a warning.  Only Scheme48/scsh and SigScheme get upset
by sequential dependencies in internal defines (following R5RS strictly).

-- 
I don't know half of you half as well           John Cowan
as I should like, and I like less than half     cowan@x
of you half as well as you deserve.             http://www.ccil.org/~cowan
        --Bilbo

_______________________________________________
Scheme-reports mailing list
Scheme-reports@x
http://lists.scheme-reports.org/cgi-bin/mailman/listinfo/scheme-reports