On 2007-07-06, Alex Popescu <[EMAIL PROTECTED]> wrote: > On Jul 6, 4:20 am, Christoph Zwerschke <[EMAIL PROTECTED]> wrote: >> Alex Popescu wrote: >> > Probably the simplest solution would be to create a new exception and >> > wrapping the old one and the additional info. Unfortunately, this >> > may have a huge impact on 3rd party code that was catching the >> > original exception. So, I think you should create an utility >> > factory-like function that is either creating a new exception >> > instance as the one caught and with the additional information, >> >> Right, I have gone with that (see the example with the PoliteException >> class somewhere below). >> >> > or an utility that knows how to modify the caught exception according >> > to its type. >> >> I guess you mean something like this (simplified): >> >> except Exception, e: >> if getattr(e, 'reason'): >> e.reason += "sorry" >> else: >> e.message += "sorry" >> >> The problem is that these attribute names are not standardized and can >> change between Python versions. Not even "args" is sure, and if a class >> has "message" it does not mean that it is displayed. Therefore I think >> the first approach is better. >> >> > In the first case you will need somehow to tell to the new instance >> > exception the real stack trace, because by simply raising >> > a new one the original stack trace may get lost. >> >> Yes, but thats a different problem that is easy to solve. > > Yeah maybe for a python guy, but I am a newbie. I would really > appreciate if you can show in this thread how this can be done > in Python.
Chech out the docs for sys.exc_info(), and for the raise statement. When handling an exception, you can rethrow a different exception, but with the same traceback, by using the three-arg version of raise. See one of my earlier posts in this thread for a working example (although it didn't solve Chris's problem). -- Neil Cerutti -- http://mail.python.org/mailman/listinfo/python-list
