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PySR 0006: Type Annotations

Abstract

Always write type annotations for your functions, even if not variables. This not only allows static type checkers (ex. mypy) and runtime type checkers (ex. typegaurd) to verify the types passed to your functions, but it also provides future you, and other readers with insight as to what the function expects.

Deprecated typing types

Certain types from within typing are deprecated and have been moved into collections or other libraries. Some examples include:

  • typing.Iterable -> collections.abc.Iterable
  • typing.Iterator -> collections.abc.Iterator
  • typing.Callable -> collections.abc.Callable
  • typing.Generator -> collections.abc.Generator
  • typing.Hashable -> collections.abc.Hashable
  • typing.Deque -> collections.Deque
  • typing.OrderedDict -> collections.OrderedDict
  • typing.Type -> builtins.type
  • typing.Tuple -> builtins.tuple

Prefer using the new versions over the deprecated typing.* aliases for these specific deprecated types.

Also see: