search paths and teachpacks?? was Re: [plt-scheme] How do I get picture.plt working under DrScheme 205?

From: Allyn Dimock (dimock at
Date: Wed Sep 24 11:58:15 EDT 2003

In light of day, found no problem with Michael Sperber's picture code.
Problem was in my using the teachpack (and going off on the wrong tangent
when it didn't work).
 -- teachpack may be wrong
 -- .plt creation may have been odd
 -- path handling in drscheme's may be incompatible with setup-plt

sudo setup-plt ~/downloads/picture.plt

creates new directories ~/.plt-scheme/205/teachpack/ and
~/.plt-scheme/205/collects/ and unpacks there.

(rather than unpacking in /usr/local/share/plt/.../ )

starting drscheme and loading the teachpack did not work:
  left paint undefined.
various combinations of moving the teachpack and the collection into
/usr/local/share/plt/... did not work:
  left paint undefined.

not loading teachpack and (require (lib "" "picture"))
works fine.

Ideas?  Now that I know what works, this is a low priority, but I would
like to know if there is an incompatability in path searches between 
using a teachpack from the languages menu and executing a (require ...)

(Answer to Michael Sperber's question on procedure below.
My apologies to Michael for being a neophyte in using the DrScheme
environment and going off in the wrong direction once the teachpack
did not work.)

-- Allyn

Michael Sperber writes:
 > >>>>> "Allyn" == Allyn Dimock <dimock at> writes:
 > Allyn> I use the pictures teachpack in the MzScheme+MrEd language.
 > Allyn> I load in all the .scm files from collect/pictures in the order
 > Allyn> mit-macros, mit-support, hutils, primitives, prmpnt, hend.
 > I'm confused:  If you use the teachpack, you don't need to load any
 > of the Scheme files explicitly.  Could you give a more detailed
 > description of what it was you did?

(o) start drscheme
(o) set language to mzscheme+mred
(o) add teachpack ~/.plt-scheme/205/teachpack/
(o)  in evaluation window type
     (paint black)
     [BUG ICON] reference to undefined identifier paint
(o)  tried loading all the .scm files -- but forgot to load the .ss
     files  (got error about incompatibility with teachpack...)
(o)  (paint black)
     [BUG ICON] previously described message.
     (Perfectly reasonable to get an error since not
      loaded and requires from not executed)

What works is

(o) start drscheme
(o) (require (lib "" "picture"))  in definitions, Execute,
(o) (paint black) in interaction.

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