Exception hook should be optional for embedding IPython in GUIs

On Tue, Mar 3, 2009 at 10:19 AM, Gael Varoquaux
<email address hidden> wrote:
> Public bug reported:
>
> When embbeding IPython, the exception hook (IPython crashed.... )
> captures exception that are not IPython exceptions. It can be desirable
> not to capture any exceptions and to let the application designer deal
> with the exceptions.
>
> As such, it would be nice if the main exception hook could be disabled
> by a switch on the IPython0 instance.

I accomplish this in qt ui by:

# cruel hack to avoid subclassing and prevent crash handler
IPython.iplib.InteractiveShell.isThreaded = True

--
Ville M. Vainio
http://tinyurl.com/vainio

On Tue, Mar 03, 2009 at 08:28:03AM -0000, Ville M. Vainio wrote:
> On Tue, Mar 3, 2009 at 10:19 AM, Gael Varoquaux
> <email address hidden> wrote:
> > Public bug reported:

> > When embbeding IPython, the exception hook (IPython crashed.... )
> > captures exception that are not IPython exceptions. It can be desirable
> > not to capture any exceptions and to let the application designer deal
> > with the exceptions.

> > As such, it would be nice if the main exception hook could be disabled
> > by a switch on the IPython0 instance.

> I accomplish this in qt ui by:

> # cruel hack to avoid subclassing and prevent crash handler
> IPython.iplib.InteractiveShell.isThreaded = True

OK, that will do the trick. I believe we can close this bug report.

Thanks,

Gaël

Closing as won't fix since the solution is more of a workaround. As we refactor things, we can offer later a nicer way to do this. But I'm happy to close for now.

On Sat, Mar 14, 2009 at 12:52:18PM -0000, Fernando Perez wrote:
> Closing as won't fix since the solution is more of a workaround. As we
> refactor things, we can offer later a nicer way to do this. But I'm
> happy to close for now.

> ** Changed in: ipython
> Status: New => Won't Fix

I have just implemented this in the Enthought codebase (will move it up
to the frontend code in IPython soon).

This is simply _horrible_: module-level monkey patching. In other words:
huge side effects. I don't think this solution is acceptabe, and I'd like
this bug reopened, admitedly with a milestone set for later than 0.10.

The IPython-related code in ETS is full of similar hacks (like
monkey-patching raw_input). It renders the whole applications fragiles.

Gaël

On Sun, Mar 15, 2009 at 2:27 PM, Gael Varoquaux
<email address hidden> wrote:

> This is simply _horrible_: module-level monkey patching. In other words:
> huge side effects. I don't think this solution is acceptabe, and I'd like
> this bug reopened, admitedly with a milestone set for later than 0.10.

I agree that it's horrible. A proper solution would be to implement
the crash handler as a hook (and have current crash handler as the
default handler if hook raises TryNext).

--
Ville M. Vainio
http://tinyurl.com/vainio

On Sun, Mar 15, 2009 at 12:42:19PM -0000, Ville M. Vainio wrote:
> On Sun, Mar 15, 2009 at 2:27 PM, Gael Varoquaux
> <email address hidden> wrote:

> > This is simply _horrible_: module-level monkey patching. In other words:
> > huge side effects. I don't think this solution is acceptabe, and I'd like
> > this bug reopened, admitedly with a milestone set for later than 0.10.

> I agree that it's horrible. A proper solution would be to implement
> the crash handler as a hook (and have current crash handler as the
> default handler if hook raises TryNext).

That sounds good.

Gaël

Reopened as per feedback in thread. We'll look into it post-0.10 though.