[IPython-dev] Preventing "Oops, IPython crashed" ?

[Fernando Perez]

Hans Meine wrote:

>>There is a workaround: you can manually reset sys.excepthook to the
>>ipython  normal exception handler:
>>
>>sys.excepthook = __IPYTHON__.excepthook
>>
>>By running this line, you lose the real crash handler though, so if
>>ipython proper crashes, I will get a LOT less debug information.  Caveat
>>emptor.
> 
> 
> I think this workaround should be documented somehow.  When working with GUI 
> callbacks that possibly result in exceptions in a different thread, the long 
> traceback is much less helpful than the shiny "normal" IPython one.  
> (Congratulations on that BTW.)
> 
> Another workaround could be to color the long one, too (after all, it's mostly 
> the missing color which bugs me), and either remove that from the report.txt 
> or even send a colored report (although the usefulness depends on your mailer 
> since it's not attached but in the mail body) which you can dump to a 
> console?

The problem is that I have no way of knowing if that is being hit by a 
matplotlib exception, or an honest ipython crash.  Cross-thread exception 
handling in python is a nightmare, so all those guys fall trhough into 
sys.excepthook, where the ipython crash handler sits.  That one doesn't use 
color, because ansi escapes inside emails make a mess.

So I'm afraid I don't really know how to solve this particular problem 
cleanly.  Any ideas would be most welcome.  Specifically, a way to trap the 
mpl exceptions only would do the trick, but all try/excepts I've tried to wrap 
around the mpl threads have so far failed.

My reading of multiple posts on c.l.py on the exceptions/threads mix make it 
sound like it's a pretty explosive cocktail, so I really don't know what else 
to do.

Cheers,

f