What is the difference between first-class and higher-order functions?

What is the difference between first-class and higher-order functions?

First-class functions are treated as first-class citizens in programming, meaning they can be assigned to variables, passed as arguments, and returned from other functions. Higher-order functions, on the other hand, are functions that take other functions as arguments or return them as results.

Can you give me an example of a higher-order function?

Sure! A common example is the map function in JavaScript, which takes a function as an argument and applies it to each element in an array.

What about first-class functions? Can you show me an example?

Absolutely! In JavaScript, you can assign a function to a variable like this: const greet = function() { return 'Hello!'; }. Here, greet is a first-class function.

Why are these concepts important in programming?

They are crucial for functional programming, enabling more abstract and flexible code, allowing for higher levels of code reuse and composition.