Errors and their messages

[Hans Nowak]

seb wrote:

> Hi all,
> 
> i think i've only ever followed up here before, but here goes:
> 
> The python error messages presented on the command line seem to me to
> be particularly gregious.
> 
> Say someone is looking to get schoolkids to be involved in programming
> (and python seems to be a reasonable choice here so i understand),
> then something like:
> 
> Traceback (innermost last):
>   File "<stdin>", line 1, in ?
>   File "win32com\client\__init__.py", line 13, in Dispatch
>     dispatch, userName =
> dynamic._GetGoodDispatchAndUserName(dispatch,userName,c
> lsctx)
>   File "win32com\client\dynamic.py", line 67, in
> _GetGoodDispatchAndUserName
>     return (_GetGoodDispatch(IDispatch, clsctx), userName)
>   File "win32com\client\dynamic.py", line 58, in _GetGoodDispatch
>     IDispatch = pythoncom.CoCreateInstance(IDispatch, None, clsctx,
> pythoncom.II
> D_IDispatch)
> 
> doesn't make it easy.
> 
> OK, i might be trying to do a bit more here, but even
> 
> >>> lala
> Traceback (innermost last):
>   File "<stdin>", line 1, in ?
> NameError: lala
> >>>
> 
> is cryptic.

It's not so cryptic anymore if you read the fine tutorial:

  http://www.python.org/doc/current/tut/node10.html

Error messages consist of a traceback, that tells you in what code
the exception occured, plus the exception being raised (type and
a message, e.g. NameError and "lala", in your example above).
Tracebacks are often nested, and can therefore look impressive;
they're not that difficult to figure out though.

--Hans