[concept]OOP & Tooling
Type Hints & Dataclasses
# theory
Type hints document what goes in and what comes out. Python does not enforce them at runtime, but they make code readable and let editors catch mistakes.
def add(a: int, b: int) -> int:
return a + b@dataclass writes the boilerplate for you. You declare the fields with
types and it generates __init__, __repr__, and __eq__.
from dataclasses import dataclass
@dataclass
class Point:
x: int
y: intPoint(1, 2) now prints as Point(x=1, y=2) and two points with the same
values compare equal. No hand-written __init__ needed.
# examples [2]
# example 01 · typed function
Hints describe the inputs and the return value
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# example 02 · dataclass gives you __repr__ and __eq__ free
Declare fields with types; the boilerplate is generated
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# challenges [2]
# challenge 01/02todo
Write a function add(a: int, b: int) -> int that returns the sum, then print the result of add(2, 3) in the form sum=<value>.
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# challenge 02/02todo
Use @dataclass to define a class Point with fields x: int and y: int. Create Point(1, 2) and print it. The dataclass repr should show Point(x=1, y=2).
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