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Re: The simplest compiler possible

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Albert van der Horst <albert@cherry.spenarnc.xs4all.nl> wrote:
+---------------
| Of course MacCarthy's original article gives insight.
| If you look however how lambda and environments are described,
| then try to implement them, you realize that they are leaning
| towards being pseudocode rather than executable lisp.
| E.g. lambda ask for a textual replacement system that is non-trivial.
+---------------

I don't know where you heard that idea, but it's incorrect.
In the programming language Lisp, the lambda operator does *NOT*
require a "textual replacement" of any kind [nor does evaluation
in general]. Once a form has been read -- *long* before it is
evaluated! -- there is no "text" left at all, just Lisp objects.
[Obviously, here I'm ignoring Lisp objects which happen to be
strings, but those are not necessary for evaluation to work.]

+---------------
| If it is written using only lisp it has to deal with machinecode
| in one form or another. Those who never have written a compiler
| from scratch find it hard to realize that.
+---------------

Look up the term "LAP" [Lisp Assembly Program] and you'll discover
that dealing with machine code as Lisp data is almost as old as
Lisp itself. [Hint: See Appendix C of the MIT Lisp 1.5 manual,
circa 1962.]


-Rob

-----
Rob Warnock		<rpw3@rpw3.org>
627 26th Avenue		<http://rpw3.org/>
San Mateo, CA 94403

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The simplest compiler possible albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-01-29 19:54 +0100
  Re: The simplest compiler possible Kaz Kylheku <221-501-9011@kylheku.com> - 2017-01-29 19:18 +0000
  Re: The simplest compiler possible albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-01-30 18:50 +0100
    Re: The simplest compiler possible rpw3@rpw3.org (Rob Warnock) - 2017-01-31 07:11 +0000
      Re: The simplest compiler possible Paul Rubin <no.email@nospam.invalid> - 2017-01-30 23:17 -0800
        Re: The simplest compiler possible Kaz Kylheku <221-501-9011@kylheku.com> - 2017-01-31 14:32 +0000
      Re: The simplest compiler possible albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-01-31 11:39 +0100
        Re: The simplest compiler possible Kaz Kylheku <221-501-9011@kylheku.com> - 2017-01-31 14:19 +0000
  Re: The simplest compiler possible anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-01-31 13:17 +0000
    Re: The simplest compiler possible Barry Margolin <barmar@alum.mit.edu> - 2017-01-31 15:10 -0500
  Re: The simplest compiler possible Gerard Sontag <gerardsontag@gmail.com> - 2017-02-03 01:08 -0800
    Re: The simplest compiler possible albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-02-03 10:23 +0100
      Re: The simplest compiler possible Gerard Sontag <gerardsontag@gmail.com> - 2017-02-03 02:34 -0800
    Re: The simplest compiler possible stephen@mpeforth.com (Stephen Pelc) - 2017-02-03 13:06 +0000

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