What is a match-case statement in Python?

Overview

In Python, a match-case statement is similar to a switch statement. We use a switch statement to transfer control to a particular block of code based on the value of the tested variable.

Note: Switch statements are an efficient alternative for if-else statements.

Refer Switch Statement in Java

The match-case statement is similar to switch statements in object-oriented languages and is meant to make matching a structure to a case more manageable. It’s more powerful and allows for more complicated pattern matching.

The structure of a match-case is as follows:

match variable:
    case matching_value_1: statement_1
    case matching_value_2: statement_2
    case matching_value_3: statement_3

Let’s look at different examples to understand more.

Example 1

This example highlights a simple match-case statement.

character = 'A'
match character:
    case 'A':
        print("character is A")
    case 'B':
        print("character is B")
    case 'C':
        print("character is C")

Example 2

We can also use a pipe operator | to specify multiple values that a case can match.

character = 'M'
match character:
    case 'A' | 'Z':
        print("character is A or Z")
    case 'B' | 'D':
        print("character is B or D")
    case 'C' | 'M':
        print("character is C or M")

Example 3

We can add default cases to the match-case expressions in Python. As Python evaluates against a pattern, we can easily substitute a default case with a disposable underscore (_).

character = 'V'
match character:
    case 'A' | 'Z':
        print("character is A or Z")
    case 'B' | 'D':
        print("character is B or D")
    case 'C' | 'M':
        print("character is C or M")
    case _:
        print("Unknown character given")

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