[Visualpython-users] Problems with exception handling in vpython on Linux

[Guenter S. <Gue...@ph...>]

I ran into a number of problems with vpython on Linux which appear to be 
all related. The problems do not happen in Windows. My system is ubuntu 
9.04, vpython 5.12 compiled from source (5.11 gives identical results).

Thee common feature I see on Linux is, whenever vpython raises an 
exception, python seg. faults.

Example 1:

In [1]: from visual import *

In [2]: a = vector(1,2,3)

In [3]: for i in a:
    ...:     print i
    ...:
    ...:
1.0
2.0
3.0
Segmentation fault
~ $

but the following works:

Example 2:

In [1]: from visual import *

In [2]: a = vector(1,2,3)

In [3]: for i in a:
    ...:     print i
    ...:     if i>2:
    ...:         break
    ...:
    ...:
1.0
2.0
3.0

This seems to point to the raising a StopIteration exception as the 
problem point.

Example 3:
In [1]: from visual import *

In [2]: a = [1,2,3]

In [3]: mag2(a)
Out[3]: 14.0

In [4]: a = [1,2,'x']

In [5]: mag2(a)
Segmentation fault
~ $

It should have raised a TypeError as in this case

In [1]: from visual import *

In [2]: a = [1,2,'x']

In [3]: print a[0]*a[0]+a[1]*a[1]+a[2]*a[2]
------> print(a[0]*a[0]+a[1]*a[1]+a[2]*a[2])
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)

Finally this fails as well:

Example 5:
In [1]: from visual import *

In [2]: quit()
Do you really want to exit ([y]/n)?
Segmentation fault
~ $

This error  is probably caused by a SystemExit exception.

Is something wrong with my install? Hard to see how to go wrong there, 
it's configure, make, make install and taking care of site-packages in 
ubuntu 9.04.

Thank you for your help and the great work.

Guenter Schneider