Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!mnetor!uunet!husc6!mit-eddie!uw-beaver!tektronix!oresoft!rick
From: rick@oresoft.UUCP (Rick Lahrson)
Newsgroups: comp.sys.amiga,comp.lang.misc
Subject: Re: Compilers?
Message-ID: <72@oresoft.UUCP>
Date: Wed, 31-Dec-69 18:59:59 EDT
Article-I.D.: oresoft.72
Posted: Wed Dec 31 18:59:59 1969
Date-Received: Wed, 16-Sep-87 02:24:31 EDT
References: <1708@amiga.amiga.UUCP> <581@sugar.UUCP> <935@unicus.UUCP> <66@oresoft.UUCP> <5042@jade.BERKELEY.EDU> <70@oresoft.UUCP> <5073@jade.BERKELEY.EDU>
Reply-To: rick@oresoft.UUCP (Rick Lahrson)
Organization: Oregon Software, Portland OR
Lines: 42
Keywords: compiler assembler dwim mating
Xref: mnetor comp.sys.amiga:8357 comp.lang.misc:660

In article <5073@jade.BERKELEY.EDU> mwm@eris.BERKELEY.EDU (Mike (My watch has windows) Meyer) writes:
>... No hard feelings, I hope?

Absolutely not.  Only respect and appreciation.

><>[Referring to BCPL and it's pointers in AmigaDOS.]
>As someone else pointed out, you have two different models: the
>hardware model, and the model the language has. The compiler can't do
>anything about them; it just has to live with them. For many languages
>(Pascal, COBOL, FORTRAN, Icon, Snobol, LISP, etc.) the language model
>just has "abstract" objects in it (integers, floats, strings, etc) and
>they can be mapped to something reasonable on just about any machine.

Aye, there's the rub.  I don't find BPTR's very reasonable.

>On the other side, BCPL *insists* that the machine has words, and
>words have three properties: 1) They are at least 16 bits long. 2)
>they are long enough to hold a pointer to a word, and 3) adding 1 to
>an address gives the address of the next word. On a word address
>machine, this works just fine. But on a byte-addressed machine, you
>have to jump through to make things work.

Hmmm.  Maybe I need to learn a little bit about a language before I
bitch about its implementation. ...  Nawwww. 8-)
Apparently then, BCPL doesn't distinguish between numeric objects and
pointers?  I don't know BCPL, but if it distinguishes pointers from
other things, it could have scaled its pointer arithmetic (as C does)
in order to better fit the target machine.  Oh, well.  It's a dead horse.
We definitely have BPTR's in our lives for some time to come. 8-(

><I think this is the first time I've been publicly "Oh, horse puckied".
><Kinda makes me scared to offer further postings.  1/2  8-)
>Don't do that! Normally, your postings make lots of sense. I wanted to
>make sure nobody mistook the misinterpretation for truth! 1/2 :-).

That's just what I needed to hear.  Thanks.  Purrrr.

-- 

Rick Lahrson  ...tektronix!oresoft!rick

Disclaimer:  If I ever speak for anyone but me, I'll warn you in advance.