Re:Practical Python Programming
by pansa2 on Thursday June 18, 2020 @08:25PM
(#23569690)
Type annotations aren’t equivalent to this check, though, because they’re not enforced at runtime.
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Why should type annotation be enforced at run time? In statically typed languages there is no type checking at run time, your type system already proved the type of variable.
Because Python’s type annotations don’t prove anything. That’s why, for example, they can’t be used to increase the performance of the interpreter.
Re:Practical Python Programming
by ghostwriter on Friday June 19, 2020 @06:46AM
(#23573083)
> That’s why, for example, they can’t be used to increase the performance of the interpreter.
They can (as in - there's API for that, the rest is up to a community effort) improve performance of a final program, if type-annotated code is passed through Cython with ``annotation_typing=True`` flag:
http://docs.cython.org/en/latest/src/tutorial/pure.html#stat...
https://github.com/cython/cython/issues/1672#issuecomment-29...