[Visualpython-users] Experimental clean import capability

[Bruce S. <bas...@nc...>]

In the "For developers" section of vpython.org is a zip file
containing experimental code for doing either the convenient "from
visual import *" or a clean "import vpython". Please try this out and
post comments about whether this would meet your needs, or how it
should be changed, or offer a different scheme entirely. Once we reach
agreement, this will become a part of VPython 5.4 for Python 2.7 and
Python 3.1.

I was able to follow the suggestion to put almost everything in the
new vpython folder, so that the visual folder mostly just imports from
the vpython folder. I thought it might be possible, and clean, to put
the two modules inside one folder, but that doesn't work. I'm very
hazy on how the import search works. If you see a way to have one
folder rather than two, please explain.

As far as I can tell from my tests, there is complete backward
compatibility with existing programs.

Bruce Sherwood

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Here are the installation instructions in the accompanying README file:

1) Before making any changes to your current site-packages, make a copy of

     site-packages/visual

2) Replace site-packages/visual with the visual folder in this package.

3) Add to site-packages the vpython folder in this package.

4) From your saved copy of site-packages/visual, copy into the new
vpython folder

     cvisual.pyd (Windows) or
     cvisual.so (Mac)

5) On Windows, from your saved copy of site-packages/visual, copy the doc and
   examples folders into the new visual folder.

After making these changes, you can still use "from visual import *" if that is
convenient, but if you want to import the visual objects cleanly, import them
from the new vpython module. Here are two simple examples:

import vpython as vp
vp.box(color=vp.color.orange, material=vp.materials.wood)

from vpython import (box, color, materials)
box(color=color.orange, material=materials.wood)

There are new clean modules vpython.controls, vpython.filedialog, and
vpython.graph
that can be used instead of the old modules visual.controls,
visual.filedialog, and
visual.graph. The old modules execute "from visual import *" and are
retained because
some programs expect that behavior when importing one of these modules.