PEP 526 - var annotations and the spirit of python
bc at freeuk.com
Thu Jul 5 06:26:54 EDT 2018
On 05/07/2018 10:59, Steven D'Aprano wrote:
> But it is redundant in *that* example. Your hint is not giving any more
> information that what the reader, or type checker, can already infer.
> These are useful:
> x: Any = 3 # x can be anything, but is currently an int
> x: int = None # x can be an int, or None
> x: Union[int, str] = 'abc' # x can be either an int, or a
> # string, not just the string you see here
This is one reason I dropped type hinting from my own developments.
It's a poor, half-baked version of both true static typing, and of true
Look at Haskell for how type inference can be done well (I have to
admire it even if I don't understand it).
And at numerous other languages that are properly statically typed (Ada
being one of the most rigorous, while C++ is a nightmare).
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