[Tutor] Stack unwind using exceptions.

[bob gailer]

Noufal Ibrahim wrote:
> Kent Johnson wrote:
> [..]
>> Why not just return the value from the function and pass it up the
>> call chain? If a call fails return None. Something like this:
>
> That's what I ended up doing but the first thing occurred to me and I 
> was just wondering if there's any production code that relies on the 
> technique.
>

I use the exception technique in my Python Pipelines parser. The 
recursive routine has 6 raise statements. The exceptions are caught by 
the program that calls the recursive routine. There would be more code 
and complexity to work back up the call chain.


-- 
Bob Gailer
Chapel Hill NC
919-636-4239