Following the mypy type annotations discussions with interest. Devil's in the details though, I think it will end up just an editor hint.
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Really cute approach to reporting type errors: when there's a type error, show an example of a runtime error that the type check has prevented!
Data-Driven Techniques for Type Error Diagnosis https://escholarship.org/uc/item/59s4h4pv
Playing with optional type signatures in Python, I realise that the return type is the most important to me.
I'd much rather have a function with only a return type instead of a function with only parameter types. It's often quick to add too.
It's interesting to see the "why not Rust?" discussions around the TypeScript news that they're using Go. It shows that Rust has reached a level of maturity that it's a default for some users.
Go does seem to be in a sweet spot for AOT languages with GC though.