Thanks for the suggestion. However, I don't think it's possible or desirable for python to implement this.

There are two problems: 1) the internals of python would have to be drastically changed to support this, and 2) you'd need different syntax to support this.

For item 2, consider:

def f():
    try: return some_other_function()
    except: return 1,2

You can't distinguish between your proposed type mis-match exception and some_other_function() raising a TypeError. I suppose you could invent another exception type, but you'll always have a similar problem.

A larger problem is that this behavior would be confusing to both newcomers and existing programmers, it adds nothing that can't currently be done, and it would be a source of subtle bugs.

If you really want to explore this, I suggest working out a more complete example and bringing it up on the python-ideas mailing list.

You'll want to include code that currently exists that would be made simpler with your proposal. If you can find any such code in the standard library, that would be a bonus.

Thanks again.