Python learning series | Day-5 Types of arguments

What is arguments?

Arguments are the values passed inside the parenthesis of the function. A function can have any number of arguments separated by a comma(,).

Types of arguments in python

1. Positional Arguments
2. Keyword Arguments
3. Default Arguments
4. Arbitrary / Variable-Length Arguments

1) Positional Arguments

These are the arguments to be passed in exact order in which the parameter are defined.

def greet(name,age): print(f"hello {name},Are you {age} year old") greet("Ajay",20) 

2) Keyword Arguments

We can pass arguments with explicitly stating the parameter name followed with value(name = value), the order of arguments doesn't matters.
-The keyword name must match the parameter name

def greet(name,age): print(f"hello {name},Are you {age} year old") greet(age =20 ,name = "Ajay") 

3) Default Arguments

You can assign fallback values to parameters in the function definition(declaration). If the caller skips providing a value for that argument, the predefined default value is used.

• Default arugments must always be placed after the non-default arugments in the function definition.

def greet(name = "ajay", message): print(f"Hello {name}, {message}!") greet("harry") greet("harry", "Goodbye") 

4) Arbitrary / Variable-Length Arguments

When you do not know beforehand how many arguments a user might pass, you use variable-length arguments:
• *args (Arbitrary Positional Arguments): Prefixed with a single asterisk, it collects extra positional arguments into a tuple.
• **kwargs (Arbitrary Keyword Arguments): Prefixed with a double asterisk, it collects extra keyword arguments into a dictionary.

def dynamic_function(*args, **kwargs): print("Positional tuple:", args) print("Keyword dictionary:", kwargs) dynamic_function(1, 2, 3, status="active", role="admin") # Output: # Positional tuple: (1, 2, 3) # Keyword dictionary: {'status': 'active', 'role': 'admin'} 

4) Special boundries : Positional-Only, Keywords- Only

(/) and (*)strictly enforce how the arguments are suppied to the function

• Positional-Only(/) ---> Arguments before (/) must be passed as positional arguments not a keyword arguments.

def add(a,b,/,c): print(a+b+c) add(20,30,c=20) #valid add(a=20,30,c=30) #invalid 

• Keyword-Only(*) ---> Arguments before (*) must be passed as keyword arguments not a positional arguments.

def add(a,b,*,c): print(a+b+c) add(a=20,30,c=30) #invalid add(20,30,c=20) #invalid