Learn X By Example
Learn X By Example

    Switch in Logo

    The code example focuses on switch statements in the target language specified in the logo, which is “Python”.

    Here’s a basic switch equivalent in Python using if-elif-else:

    import datetime

# Basic switch example
i = 2
print(f"Write {i} as ", end="")
if i == 1:
    print("one")
elif i == 2:
    print("two")
elif i == 3:
    print("three")

# Multiple expressions in a case statement
current_day = datetime.datetime.now().weekday()
if current_day in (5, 6):
    print("It's the weekend")
else:
    print("It's a weekday")

# Switch with non-constant expressions
current_hour = datetime.datetime.now().hour
if current_hour < 12:
    print("It's before noon")
else:
    print("It's after noon")

# Type switch equivalent using type() and isinstance()
def what_am_i(i):
    if isinstance(i, bool):
        print("I'm a bool")
    elif isinstance(i, int):
        print("I'm an int")
    else:
        print(f"Don't know type {type(i).__name__}")

what_am_i(True)
what_am_i(1)
what_am_i("hey")

    Explanation

    Basic Switch Example

    In Python, we use if-elif-else statements to mimic switch-case logic:

    i = 2
print(f"Write {i} as ", end="")
if i == 1:
    print("one")
elif i == 2:
    print("two")
elif i == 3:
    print("three")

    Multiple Expressions in a Case Statement

    Using tuple membership to handle multiple cases:

    current_day = datetime.datetime.now().weekday()
if current_day in (5, 6):
    print("It's the weekend")
else:
    print("It's a weekday")

    Switch with Non-Constant Expressions

    Conditions based on the current time:

    current_hour = datetime.datetime.now().hour
if current_hour < 12:
    print("It's before noon")
else:
    print("It's after noon")

    Type Switch Equivalent

    Using isinstance to handle type-specific logic:

    def what_am_i(i):
    if isinstance(i, bool):
        print("I'm a bool")
    elif isinstance(i, int):
        print("I'm an int")
    else:
        print(f"Don't know type {type(i).__name__}")

what_am_i(True)
what_am_i(1)
what_am_i("hey")

    Running the Code

    To run this Python code, you can save it in a file with a .py extension and run it using the Python interpreter:

    $ python switch_example.py
Write 2 as two
It's a weekday
It's after noon
I'm a bool
I'm an int
Don't know type str

    This demonstrates how to mimic switch-case logic in Python using if-elif-else constructs while focusing on maintaining idiomatic code.

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