7 Things I Should’ve Learnt Much Earlier For Python Functions

 

Closures

What: Functions that capture the local state of the environment in which they were created.

Why: Useful for creating function factories or decorators.

def outer(x):

    def inner(y):

        return x + y

    return inner

add_five = outer(5)

print(add_five(10))  

#clcoding.com

Function Annotations

What: Provides a way to attach metadata to function arguments and return values.

Why: Helps in providing hints about the expected data types, which improves code readability.

def add(a: int, b: int) -> int:

    return a + b

print(add(2, 3))  

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Returning Multiple Values

What: Python allows functions to return multiple values as a tuple.

Why: Enables you to return complex data without creating a class or data structure.

def get_name_age():

    name = "clcoding"

    age = 30

    return name, age

name, age = get_name_age()

print(name, age)  

#clcoding.com

clcoding 30

Docstrings

What: Strings that describe what a function does, placed as the first line within the function body.

Why: Helps in documenting your code, making it more understandable.

def add(a, b):

    """Returns the sum of two numbers."""

    return a + b

print(add.__doc__)  

#clcoding.com

Returns the sum of two numbers.

Lambda Functions

What: Small, anonymous functions defined using lambda.

Why: Useful for short functions that are used once or passed as arguments to higher-order functions.

double = lambda x: x * 2

print(double(5))  

items = [1, 2, 3, 4, 5]

squared = list(map(lambda x: x**2, items))

print(squared)  

#clcoding.com

10

[1, 4, 9, 16, 25]

***args and kwargs

What: args and *kwargs allow functions to accept an arbitrary number of positional and keyword arguments, respectively.

Why: Useful when you don’t know in advance how many arguments will be passed.

def print_args(*args):

    for arg in args:

        print(arg)

print_args(1, 2, 3)  

def print_kwargs(**kwargs):

    for key, value in kwargs.items():

        print(f"{key}: {value}")

print_kwargs(name="clcoding", age=30)

#clcoding.com

1

2

3

name: clcoding

age: 30

Default Arguments

What: Allows you to set default values for function parameters.

Why: Makes your functions more flexible and easier to use.

def greet(name="Guest"):

    print(f"Hello, {name}!")

greet()             

greet("clcoding")   

#clcoding.com

Hello, Guest!

Hello, clcoding!