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From: bson@rice-chex.ai.mit.edu (Jan Brittenson)
Newsgroups: comp.sys.handhelds
Subject: Re: Lists in the HP48
Message-ID: <12017@life.ai.mit.edu>
Date: 24 Nov 90 03:11:28 GMT
References: <kskalb.659353921@faui1f>
Sender: news@ai.mit.edu
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In article <kskalb.659353921@faui1f> 
   kskalb@faui1f.informatik.uni-erlangen.de (Klaus Kalb) writes:

 > I want to know how the HP48 implements the data type LIST.  Are they
 > just plain, ordinary linked lists or is there something more
 > spohisticated going on ?

   No, they're not cons cell lists, or linked in any way. Lists are
simply a List data type (#2a74) followed by the contents and
terminated with an End (#31b2). Like in a program, data may be of any
type, either in-line or somewhere else. (I.e. there may be either data
or pointers to data, or both randomly intermixed.) They can be
regarded (sort of) as CDR-coded lists, or hunks, or functionally (not
implementationally) like (make-array ... :element-type t) Common Lisp
arrays.

   RPL arrays differ by being restricted to a single type - real or
complex (has anyone attempted to synthesize an array of some other
type, like Character?), which allows for faster element address
calculations.