1. Introduction
The built-in function dir(__builtins__) in Python is used to list out all the available built-in functions, classes, and variables in Python. The __builtins__ module is a built-in module that provides a collection of commonly used functions, classes, and variables.
2. The dir() Function
The dir() function is a powerful built-in function in Python that returns a list of names in the current local scope or a specified object. If no parameter is provided, the dir() function returns a list of names in the current local scope.
To view the names specified in the __builtins__ module, we can pass the __builtins__ object as a parameter to the dir() function. This will give us a list of all the names available in the __builtins__ module.
dir(__builtins__)2.1 Example Output
['ArithmeticError', 'AssertionError', 'AttributeError', 'BaseException', 'BlockingIOError', 'BrokenPipeError', 'BufferError', 'BytesWarning', ...]The output of the dir(__builtins__) function is a list of strings, each representing a name available in the __builtins__ module. Each name corresponds to a built-in function, class, or variable in Python.
3. Exploring the Built-in Functions
Now that we have obtained the list of names in the __builtins__ module using the dir() function, let's explore some of the important built-in functions offered by Python.
3.1 print()
The print() function is one of the most commonly used built-in functions in Python. It is used to output text or other data to the standard output, which is usually the console.
print("Hello, World!")Important: The print() function is available in the __builtins__ module, and is supported in both Python 2 and Python 3.
3.2 len()
The len() function is another commonly used built-in function in Python. It is used to get the length or the number of items in an object such as a string, list, tuple, dictionary, etc.
name = "John"
length = len(name)
print(length) # Output: 4
3.3 type()
The type() function is used to determine the type of an object. It returns the type as a string.
num = 10
print(type(num)) # Output: <class 'int'>
Important: The type() function is a powerful tool for debugging and understanding the structure of your data.
4. Conclusion
In this article, we explored the dir(__builtins__) function in Python, which is used to get a list of names in the __builtins__ module. We also explored some of the important built-in functions offered by Python, such as print(), len(), and type().
The dir() function can be used to explore other modules and objects in Python, not just the __builtins__ module. It is a powerful tool for discovering the available functions, classes, and variables in Python.
By understanding the available built-in functions in Python, you can write more efficient and concise code. It is important to familiarize yourself with the built-in functions and their usage to become a proficient Python developer.