Re: painter implementation for picture language in SICP

[David Liu]

Thanks; I managed to get a lot farther in loading book's painter files [1] using those instructions for loading the 6001 package (also, I noticed that when building from the x86_64 binary tarball, there's a --with-6001 option that can be passed to ./configure, but that option seems to have no effect besides generating a seemingly useless src/6001/Makefile). I had to copy the 6001 dir to the mit-scheme lib dir (and also use the binary installation from the GNU site rather than the Debian package) in order to get it to work.

Anyway, to get a bit further, I made some other minor obvious changes (mostly just filename path fixes, no actual logic changes) to the ".scm" files at [1]. Then, I tried loading "psgo.scm" managed to get past a few other choke points, but ran into some kind of UTF error [2] while loading the "fovnder.pgm" picture. I'm pretty sure this error was not caused by any of the minor changes I made. Any idea how I can get past this? I would be happy to provide more detailed repro instructions if necessary.

[1] https://mitpress.mit.edu/sites/default/files/sicp/psets/ps4hnd/readme.html

[2] 

  Illegal UTF-8 initial byte: 254

 S0  (initial-byte->utf8-char-length (peek-byte ib))
 S1  ((input-buffer-normalizer ib) ib)
 S2  (defer port)
 S3  (input-port/read-char port)
 S4  (read-char port)
 S5  (proc count)
 S6  (proc count)
 S7  (side-effecting-iter width (lambda (n) (let ((nth-row (vector-ref data ...
 S8  (receiver port)
    R0  (pgm-file->picture file-name)
 S9  (pgm-file->picture file-name)
    R0  (picture->painter (pgm-file->picture file-name))
    R1  (load-painter "~/Downloads/temp/fovnder.pgm")
 S10 (load-painter "~/Downloads/temp/fovnder.pgm")
    R0  (define fovnder (load-painter "~/Downloads/temp/fovnder.pgm"))

On Wed, Dec 25, 2019 at 11:39 PM Taylor R Campbell <address@hidden> wrote:

> Date: Wed, 25 Dec 2019 14:28:35 -0500
> From: David Liu <address@hidden>
>
> Thanks Taylor for the tip. I made the flo:vector replacements and the next
> complaint it gives me is that make-picture is not defined. I'm currently
> using the Debian 10 package version of MIT-scheme so src/6001 is not
> included. I downloaded the src tarball and noticed that make-picture is
> indeed defined in pic-reco.scm. There's a 6001.pkg file which I tried to
> load, but ran into the undefined "global-definitions" and "define-package"
> functions. What is the intended way to load the definitions in src/6001?

This is a legacy `package' description.  What you do with it is more
or less as follows:

(cd "/path/to/6001")
(load "6001.sf")
(load "6001.cbf")
(load "make")

The 6001.sf script processes the 6001.pkg file and macro-expands the
source files into .bin files.  The 6001.cbf script compiles the
macro-expanded files into machine code .com files.  The make.scm
script loads it all up.  Then you can interactively enter the student
environment with:

(ge '(student))

Subsequent input at the REPL will be done in the (student) package
with all the bindings described in 6001.pkg.

(Probably all of this package business will go away in the near future
when we finish transitioning to R7RS libraries, but I don't know when
that might happen.)