Python match-case

Satellite · Control Flow

Structural Pattern Matching

`match-case` brings robust pattern matching to Python. Handle complex payloads and state machines with clarity.

Study patternsSee guard clauses

Syntax

match command:
    case "quit":
        sys.exit()
    case "hello":
        print("Hello!")
    case _:
        print(f"Unknown command: {command}")

• _ is a wildcard that matches anything.

Matching data structures

match event:
    case {"type": "user.created", "payload": payload}:
        handle_user(payload)
    case {"type": "invoice.failed"}:
        alert_finance()
    case [first, *rest]:
        process(first, rest)

• Patterns can match literals, sequences, dictionaries, and class instances.
• Use *rest to capture remaining elements in sequences.

Guards

match payload:
    case {"type": "user", "active": True} if payload["tier"] == "pro":
        onboard_pro_user(payload)

Guards add Boolean conditions to pattern matches.

Tips

• Order matters; the first matching case executes.
• Keep cases simple; extract handlers for complex logic.
• Requires Python 3.10+.

Next up in your learning path

Classic conditionals

Know when simple if/elif is cleaner.

Companion

Control flow pillar

See how match-case fits into broader patterns.

Reference

Pattern matching docs

Deep dive into advanced syntax later.

External