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Why does my Macro get expanded 8 times?

    Date: Wed, 6 Jul 88 12:26 CDT
    From: David Vinayak Wallace <Gumby@MCC.COM>

	Date: Wed, 6 Jul 88 10:13 EDT
	From: DLA@JASPER.SCRC.Symbolics.COM (David L. Andre)

	    Date: Sat, 2 Jul 88 00:41 EDT
	    From: Salem@Think.COM (Jim Salem)

	    If the definition of CLI::EXCASE were changed to have a NIL after the LET, ECASEs would
	    macroexpand twice as fast.  [Anyone listening there at Symbolics ?]

	Okay, I fixed the our development system.  It will be in the Ivory

    How does this manage to do the right thing?  According to CLtL p 60 you
    can have any number of declarations and documentation strings (although
    it's not clear what multiple doc strings imply) before the body of the
    expression.  P 153 restates this for all cases where declarations may
    appear.  So it seems that merely expanding the first form in the body
    can't be enough; you have to keep expanding until you expand into
    something which isn't a declaration

And NIL isn't a declaration, so that answers your question.

					(it doesn't appear that you can
    expand into a documentation string, although if you allow a macro to
    expand into a declaration, which I think is bogus, you should allow the
    same for doc strings).

    One way to improve this would be to use macromemo, and/or have a flag
    which disables this "feature."