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Re: (declare (type fixnum ---)) considered etc.



	
    Date: Wed, 23 Jul 86 12:42 EDT
    From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
    To: Rob MacLachlan <RAM@C.CS.CMU.EDU>,
	   David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
    Subject: (declare (type fixnum ---)) considered etc.
    In-Reply-To: <RAM.12224983442.BABYL@C.CS.CMU.EDU>
    Message-ID: <860723124252.9.DCP@FIREBIRD.SCRC.Symbolics.COM>
    
	Date: Wed, 23 Jul 1986  10:39 EDT
	From: Rob MacLachlan <RAM@C.CS.CMU.EDU>
    
    
	    Well, I had previously believed that the FIXNUM declaration was
	reasonable, but this was based on the erroneous belief that an array
	index must be a fixnum.  If it is fact the case that some
	implementations have small (2^16) fixnums, then this is a serious
	source of non-portability.  A possible solution would be to have an
	INDEX type which is (INTEGER 0 (ARRAY-DIMENSION-LIMIT)).
    
My solution is to write (integer 0 #.array-dimension-limit).
It works just fine.

With such CL constants, I don't see the need for a FIXNUM type specifier.

-- Nick