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match Statement in Python introduced in Python 3.10

The match statement allows you to compare a variable against different patterns and execute corresponding code blocks. much like the switch statement in other languages.

  • match: Used to compare the variable against different patterns.
  • case: Each potential pattern the variable could match.
  • _: The wildcard pattern, acting as a default case if no other pattern matches.

This feature is useful for matching complex data structures and handling various cases in a more readable way than using multiple if statements.

Syntax: ​

python
match variable:
    case pattern1:
        # block of code if pattern1 matches
    case pattern2:
        # block of code if pattern2 matches
    case _:
        # block of code if no pattern matches (default case)

Example: ​

python
name = input("What is your name? ")
match name:
    case "Harry":
        print("Gryffindor")
    case "Hermione":
        print("Gryffindor")
    case "Draco":
        print("Slytherin")
    case _:  # Default case
        print("Who?")
Gryffindor (if the name is Harry or Hermione)
Slytherin (if the name is Draco)
Who? (if the name is something else)

Using the | (OR) Operator in match Cases ​

The | (vertical bar) can be used to match multiple patterns (like an "OR" operator).

python
name = input("What is your name? ")
match name:
    case "Harry" | "Hermione" | "Ron":
        print("Gryffindor")
    case "Draco":
        print("Slytherin")
    case _:  # Default case
        print("Who?")
Gryffindor (if the name is Harry, Hermione, or Ron)
Slytherin (if the name is Draco)
Who? (if the name is something else)

Matching Complex Data Structures ​

You can use match to handle complex data structures, such as tuples:

python
def describe_shape(shape):
    match shape:
        case ("circle", radius):
            print(f"A circle with radius {radius}")
        case ("rectangle", width, height):
            print(f"A rectangle with width {width} and height {height}")
        case _:
            print("Unknown shape")

describe_shape(("circle", 5))
describe_shape(("rectangle", 4, 7))
describe_shape(("triangle", 3))

# Output:
# A circle with radius 5
# A rectangle with width 4 and height 7
# Unknown shape