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

meaning of local define

    Date: Sat, 29 Mar 1986  17:07 EST

        Date: Saturday, 29 March 1986  16:57-EST
        From: Jonathan A Rees <JAR at MC.LCS.MIT.EDU>

        My BNF, and the current RRRS, say that DEFINE's can't occur in
        BEGIN's; does anyone have any problem with that?  If so, what
        should it mean?

    I have a small problem with that: as always, it is necessary to be
    able to write macros that expand into multiple definitions.  So MIT
    Scheme takes the position that a BEGIN appearing anywhere that a
    DEFINE may appear is allowed to contain DEFINEs.  This seems to solve
    the problem perfectly adequately, and is very easy to implement.

Agreed, but it's also a compatible extension, presumably one added that
would be added when macros are, so it doesn't need to be documented.