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by hardwaresofton 3800 days ago
Has anyone ever tried to implement optional typing in python with just generators?

It seems like a generator like @Signature(...input types, output type) would solve this problem with limited language changes, and would work in python 2/3?
1 comments
justusw 3800 days ago
Do you mean decorators? A solution like that exists and has been used for a while. It really is only usable for run-time type-checks. See here: https://github.com/dobarkod/typedecorator

With type annotations you can have static guarantees, which decorators will not be able to provide, as decorator methods will be called and resolved only during runtime. Objects imported from `types` hopefully will not.

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hardwaresofton 3800 days ago
Yeah, that's what I meant to type, thanks.

https://github.com/dobarkod/typedecorator is interesting -- I was imagining type signatures more like haskell's:

  addNumber :: Int -> Int -> Int
translating to something like

  @TypeSignature([int, int, int])
  
  def add_number(a,b):
      ....
It's just as possible to have the compile-time program that's doing the checking process the decorators.
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