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*To*: Guy.Steele at CMU-10A*Subject*: Re: Comment on HAULONG*From*: JonL at PARC-MAXC*Date*: Tue, 20 Jul 1982 21:33:00 -0000*Cc*: common-lisp at SU-AI, Kaplan@PARC*In-reply-to*: Guy.Steele's message of 7 July 1982 2244-EDT (Wednesday)

I'm a little late in commenting on this, but before anything drastic is done, perhaps the following should be considered: HAULONG was clearly defined as "computer" operation. Attempts to put it on a mathematical footing apparently only make it more obscure. It's intent is to count the number of "informational" bits in two's-complement number, and it's encoding in MacLisp simply takes the magnitude first, before "counting" the bits. Thus I agree with EAK that ceiling(log2(abs(integer)+1)) is a poor definition for HAULONG, and my solution would be to abandon the mathematical-based definition altogether. I think it would be even worse to give it a name which implied that it had some such simple mathematical property. In general, as we discovered with the problem of printing out bitstrings "in reverse order", there is a conflict with standard mathematical notation for integers, and a computer users attempt to bitstrings as integers. HAULONG stands in the middle of this conflict.