exceptions

[Michael Hudson]

Alexander Schmolck <a.schmolck at gmx.net> writes:

> Scott David Daniels <Scott.Daniels at Acm.Org> writes:
> 
> > Calvin Spealman wrote:
> >> ...
> >> Have to admit tho, a continue feature might be useful. Some languages have
> >> this, don't they? The thing is, Where exactly to continue? Should you retry
> >> whatever raised the exception, continue just after it, at the beginning of
> >> that line, or what?
> >>
> > See this older thread:
> >    <http://groups.google.com/groups?threadm=3edd6118%241%40nntp0.pdx.net>
> >
> > Xerox's experience (in deliberately removing the "continue from
> > exception" language feature) I found very instructive.
> 
> Did this language support working interactively? If so I'd be pretty surprised
> to hear that no one found it useful to be able to manually fix things and
> continue execution; not being able to do so is presumably my number one gripe
> with python [1] -- it annoys me no end if I need to start an expensive
> computation from scratch because some trivial and easily fixable problem
> occured towards the end of the computation (sometimes it is possible to
> salvage stuff by hand by pickling things from the appropriate post-mortem
> frame, but I'd *much* prefer being able to say: foo=some_value; resume).

I'd like this too.  It might be quite hard to implement
non-disruptively but I haven't thought about it too hard.  Would make
an excellent project for a master's thesis, IMHO.

> Footnotes: 
> [1]  Number 2 would be the stupid try: finally: idiom which also seems to
>      screw up tracebacks

?

>      (which has occasionally led me to get rid of them completely
>      while debugging -- surely not a good thinge). My other gripes
>      are again related to python's limitations for interactive
>      software development -- I rather like python, but I really wish
>      it did that better.

What do you mean here, specifically?

I find I can do interactive development in Python most of the time (I
do wish it was more possible with PyObjC, though).

Cheers,
mwh

-- 
  I think perhaps we should have electoral collages and construct
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