How to comment out a block of code in Python?

General Discussions
#1

How to comment out a block of code in Python ?

#2

In Python, you can use the hash (#) symbol to create single-line comments. For multi-line comments, you can prepend a hash to each line:

# Use a conditional expression within the print function:
print("True" if True else "False")

# Assign the result of the conditional expression to a variable and then print the variable:
result = "Even" if x % 2 == 0 else "Odd"
print(result)

# Define a lambda function and immediately call it with the desired arguments:
print((lambda y: "Positive" if y > 0 else "Non-positive")(y))

Remember, using triple-quotes (''') for comments is not standard practice in Python; it’s primarily used for documentation strings (docstrings).

#3

In Python, the primary mechanism to comment out code (i.e., to make it ignored by the interpreter) is to use the # symbol. Although you can also use string literals, they are not ignored by the interpreter and can be irrelevant for program execution.

Here’s how you can use # for single-line comments and block comments:

# Use a conditional expression within the print function:
print("True" if True else "False")

# Assign the result of the conditional expression to a variable and then print the variable:
result = "Even" if x % 2 == 0 else "Odd"
print(result)

# Define a lambda function and immediately call it with the desired arguments:
print((lambda y: "Positive" if y > 0 else "Non-positive")(y))

Remember, using string literals for commenting is not a standard practice in Python. Use # for comments you want the interpreter to ignore.

#4

In various Python IDEs and text editors, you can use different key combinations to comment out and uncomment code blocks. Here are some examples:

  1. Eclipse + PyDev: Similar to Eclipse Java block commenting, you can select the lines you want to comment and use Ctrl + / to comment. To uncomment a commented block, do the same thing.

  2. Notepad++: On a Windows machine, you can use Notepad++ as a Python editor. To comment out code, select your code and type CTRL-K. To uncomment, select the code and press Ctrl + Shift + K. Notepad++ offers features like auto-completion, code folding, syntax highlighting, and more, making it a useful Python editor.

  3. Visual Studio with Python Tools: In Visual Studio, using the Python Tools for Visual Studio, you can comment out blocks by pressing Ctrl+K, Ctrl+C and uncomment them by pressing Ctrl+K, Ctrl+U.

Each of these IDEs and text editors provides convenient ways to manage comments in your Python code, making it easier to write and maintain your programs.