What is the difference between dir(), globals() and locals() functions in Python?

The Python built-in functions, dir(), globals(), and locals() are used to provide insights into the objects, variables, and identifiers present in various scopes.

They might look similar, but each function serves a different purpose and behaves differently depending on where and how it is used.

Python dir() Function

The Python dir() function is used to list the names in the current local scope or the attributes of an object. If no argument is passed, it returns the list of names in the current local scope.

dir(object)

Example

Let's look at the following example, where we are going to use the dir() function without arguments −

a = 11
def demo():
    b = 12
    print(dir())
demo()

['b']

Using dir() with Objects

You can also pass an object to dir() to see its attributes and methods −

numbers = [1, 2, 3]
print(dir(numbers)[:5])  # Show first 5 attributes

['__add__', '__class__', '__class_getitem__', '__contains__', '__delattr__']

Python globals() Function

The Python globals() function returns a dictionary representing the current global symbol table. It includes all the global variables and functions defined at the module level.

globals()

Example

In the following example, we are going to use the globals() function to access the global variables −

a = 112
b = "TutorialsPoint"
print(globals()['a'])
print(globals()['b'])

112
TutorialsPoint

Python locals() Function

The Python locals() function returns a dictionary representing the current local symbol table. When invoked inside a function, it reflects the function's local namespace.

locals()

Example

Consider the following example, where we are going to use the locals() inside a function to inspect all the local variables −

def demo():
    a = "Welcome"
    b = "Hi"
    print(locals())
demo()

{'a': 'Welcome', 'b': 'Hi'}

Key Differences

Practical Comparison

Here's a comprehensive example showing all three functions in action −

global_var = "I am global"

def compare_functions():
    local_var = "I am local"
    
    print("dir():", dir())
    print("\nlocals():", locals())
    print("\nglobals() keys (first 5):", list(globals().keys())[:5])

compare_functions()

dir(): ['local_var']

locals(): {'local_var': 'I am local'}

globals() keys (first 5): ['__name__', '__doc__', '__package__', '__loader__', '__spec__']

Conclusion

Use dir() to list available names or object attributes, globals() to access global variables as a dictionary, and locals() to inspect local variables within functions. Each serves a specific purpose in Python introspection and debugging.