What are some examples of functional programming in different languages?

What are some examples of functional programming in different languages?

Functional programming is a programming paradigm that treats computation as the evaluation of mathematical functions. Here are some examples in various languages:

1. Haskell: A purely functional language where functions are first-class citizens. Example: map function to apply a function to a list.
2. Scala: Combines object-oriented and functional programming. Example: Using fold to reduce a collection.
3. JavaScript: Supports functional programming with first-class functions. Example: Using reduce to sum an array.
4. Python: Has functional features like map, filter, and lambda functions. Example: Using filter to get even numbers from a list.

Can you give me a specific code example in JavaScript?

Sure! Here's a simple example using the map function in JavaScript:

const numbers = [1, 2, 3, 4, 5];
const squares = numbers.map(num => num * num);
console.log(squares); // Output: [1, 4, 9, 16, 25]

This code takes an array of numbers and returns a new array containing their squares.

What about an example in Python?

Here's a Python example using the filter function:

numbers = [1, 2, 3, 4, 5]
even_numbers = list(filter(lambda x: x % 2 == 0, numbers))
print(even_numbers)  # Output: [2, 4]

This code filters out the even numbers from the list.

Are there any advantages to using functional programming?

Yes, functional programming offers several advantages:

1. Immutability: Reduces side effects and makes code easier to reason about.
2. Higher-order functions: Allows for more abstract and reusable code.
3. Easier testing: Pure functions are easier to test since they don't depend on external state.