BruceSherwood
commented
11 years ago It is well known that one should never import a module in the form "from visual import ", but this is a feature, not a bug, in the VPython environment. The first page of the full user documentation (http://vpython.org/contents/docs/index.html) explains to expert programmers what to use instead of "from visual import ".
The biggest number of VPython users, by far, is the many thousands of university engineering and science students who write short VPython programs every semester in the context of the Matter & Interactions physics curriculum. Very few of these students have ever written a computer program before, yet it is important in their physics education that they nevertheless write Python programs with 3D animations to learn the essence of computational modeling. Because the physics course is very crowded, it is not possible to teach more about programming (or computer science) than an extremely small subset of concepts: sequential execution, variable, assignment, while loop. Every addition to the set represents a major pedagogical cost, which is why we teach the use of "from visual import *". Not only that, but this import also imports numpy and the most important math functions, such as sin, cos, and sqrt. In other words, this is the Python motto "Batteries included" with a vengeance.
In the case of site-packages/visual/examples, these are all very short programs that can be of use to students who have been using "from visual import ". The user documentation also assumes this import, as is mentioned in the link given above. In the case of the vidle2 and vidle3 files, the important thing to know is that VIDLE (for Python 2 or 3) is a modification of the official IDLE editor packages with the Pythons distributed at python.org; the details of why this fork are somewhat lengthy, but the novice users need these modifications. The many instances of "from tkinter import " or "from Tkinter import *" are in the original IDLE code. I've been waiting several years for IDLE to catch up with VIDLE, and to be distributed with the standard Pythons, in which case VIDLE will be removed from the VPython repository. Happily, there has recently been major activity in the IDLE development community, so I'm cautiously optimistic that the logjam will be broken.
The program compilevisual.py is just used (on Windows) to make sure all binaries of .py files have been created, before building an installer.
The few other files that have "from visual import *" have them in order to make this statement work in user programs.
In short, there really isn't anything in the repository that needs fixing in this regard. What is there is all completely intentional. The criteria for goodness and badness are not the same as in most projects, because few projects are aimed at supporting novice programmers writing programs that generate navigable real-time 3D animations. Obviously any improvements to the underlying C++ and Python system code would be all to the good, but that's a different issue.
glarrain
SethMMorton
As PEP8 says, wildcard imports should be avoided.
Currently, this happens 141 times inside this repository (
grep -r "import \*" ./, without considering those in docs files).