[Python-ideas] Type hints for functions with side-effects and for functions raising exceptions

[Christopher Barker]

On Wed, Feb 20, 2019 at 11:52 PM Ben Rudiak-Gould <benrudiak at gmail.com>
wrote:

> Other functions also conceptually have three ways of returning:
> ordinary return with a value, a documented special return like
> KeyError, and pass-through exceptions.


well, I wouldn't call that three ways of returning...

But yes, there is no (easy) way to distinguish an Exception raised by the
function you called, and one raised somewhere deeper that.

And I have been bitten by that more than once. It makes "Easier to ask
forgiveness than permission" kind of tricky.

But I've found that good unit tests help a lot.

And Exception handling is messy -- the point made by the OP, I'm not sure
there's a better way to do it.

-CHB

-- 
Christopher Barker, PhD

Python Language Consulting
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