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Compiling CASE

    Date:  Wed, 8 Apr 87 01:39 EDT
    From: Hvatum@mit-multics.arpa

    From: Steve Bacher (C.S.Draper Lab)
    The question of CASE compiling into a computed GOTO uncovers an
    interesting dilemma.  Should the compiler have special knowledge
    about certain forms which are normally macro calls, because it knows
    that they can be compiled into particular machine-code sequences,
    or should it always honor the macroexpansion?  Consider the case
    (n.p.i.) where the user provides an alternate macro definition for
    his/her own use (possibly because he/she doesn't remember that
    there already is a CASE macro).

The compiler can have special knowledge of particular macros, as long as
it ignores this special knowledge if the user redefines the macros.
MIT-derived Lisp Machines also allow users to add to the compiler's