[Python-Dev] capturing RETURN_VALUE

[Christian Tismer]

Tim Peters wrote:

...

> The point was that exceptions and returns act the same way: 
> RETURN_VALUE isn't unique here, it's just another instance of leaving
> a try-block's suite, the same in this respect as an exception or a
> break statement.  That's why it's reliable over time:  it's a general
> mechanism at work, not an arbitrary hack specific to RETURN_VALUE.

Yes, that was special for me: That return is _not_ special.
I should have known because I know the implementation so
very well, but I always felt that return is something final.
Maybe it would make sense to add a few sentences about
this fact somewhere (where?) in the docs; It was quite
remarkable for me.

Actually, there is nothing final in Python: It is not possible
to deduce from an inner code block whether it will be able
to finish the enclosing function, unless you know that your
code block consumes 20 block levels (and the latter is
probably a much less reliable fact. :-)

return-finally-break - ly y'rs -- chris
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