PEP 8 in Python 3.12: writing readable match/case blocks

Tip of the week

Python's match/case (3.10+) is powerful, but poorly indented it becomes hard to read. PEP 8 recommends indenting each case one level inside match, keeping lines within 79 characters and using short if guards.

match command.split():
    case ["go", direction] if direction in {"north", "south"}:
        move(direction)
    case ["quit" | "exit"]:
        shutdown()
    case _:
        print("Comando desconocido")

Quick rules

• One case per pattern; avoid guards with more than one condition.
• Use | to group alternatives instead of repeating branches.
• Always end with case _: so unexpected input is not silently ignored.

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