Python is DOOMED! Again!
marfig at gmail.com
Thu Jan 22 12:06:33 CET 2015
> I'd rather see a real-world example that can't be solved with either
> better design or some simple aliases. (And yes, the type hinting does
> allow for aliases.)
Python is a duck-typing language, Chris. It is in its nature -- and we have
been taught -- to ignore types and care only about operators. This means
one of the most common design decisions in Python is exactly to code functions
that are type ignorant. That is exactly why we need Type Hinting, because
duck-typing complicates static analysis. And that is exactly why the Unions
factory are a necessary part of the type hinting mechanism in PEP 484.
You will be seeing lots and lots of Unions in type annotated code once it
gets implemented. And it's not because of the complexity of Unions syntax
that I should now care about refactoring my code. That is a no-no.
If you don't know of any real-life example of python functions that will
eventually force you into annotate them with unions syntax, look no further
than your standard library. And also start questioning if you aren't complicating
your own code with unnecessary function overloads.
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