Python Type Hints

5min talk on Python Type Hints. Presented at newhaven.io

1. Type Hints
2. José Padilla
3. Work Training
4. Work Open Source
5. PEP 3107
7. PEP 484
9. no type checking happens at runtime
10. static analysis refactoring runtime type checking code generation
11. static analysis refactoring runtime type checking code generation
13. Common built-in types
27. Generics
30. mypy
31. static type checker
32. $ pip install mypy
33. $ python app.py
35. $ python app.py f 1 Traceback (most recent call last): File "app.py", line 12, in <module> print(first(1)) # TypeError File "app.py", line 7, in first return seq[0] TypeError: 'int' object is not subscriptable
36. $ mypy app.py
37. $ mypy app.py main.py:12: error: Argument 1 to "first" has incompatible type "int"; expected "Sequence[<nothing>]"
39. mypy-lang.org
40. Python will remain a dynamically typed language
41. Thanks! jpadilla.com twitter.com/@jpadilla_ github.com/jpadilla