Re: [boost] [python] can I stop iteration without exception being thrown?

From: Bruno Lalande (bruno.lalande_at_[hidden])
Date: 2008-06-11 06:26:14

>> Gennadiy Rozental wrote:
>> > This code causes an exception being thrown to stop iteration. I just
>> > wonder if
>> > there is means to avoid it.
>> >
>> Out of curiosity, what's the problem with code throwing an exception, as
>> long as it is properly caught ?
>
> In general? Setting aside potential performance consequences, exceptions have to
> be used only to report error conditions, not as end of loop indicator.

Beside the fact that I completely agree with you (but probably because
I'm a C++ developer), you have to be aware that Python and C++
philosophies differ dramatically. On this precise point, while C++
developers are attached to a well-defined balance between return codes
and exceptions, Python has pushed the use of exceptions to an extreme.
This often leads to things that are considered as worst practices
and/or beginner mistakes in other languages, like the fact of stopping
an iteration by throwing. In Python, the assertion that "exceptions
should only handle errors" is unfortunately false.

Bruno