Here is the interview question prompt, presented for reference.

Composition is putting two or more different things together, and getting a combination of the inputs as a result. In terms of programming, composition is often used for combining multiple functions and getting a result at the end. Using composition leads to a cleaner and much more compact code.

If we want to call multiple functions, at different places in our application, we can write a function that will do this. This type of function is called a pipe, since it puts the functions together and returns a single output.

A pipe function would have the following functionality:

Suppose we have some simple functions like this:

const times = (y) =>  (x) => x * y
const plus = (y) => (x) => x + y
const subtract = (y) =>  (x) => x - y
const divide = (y) => (x) => x / y

The pipe() would be used to generate new functions:

pipe([
  times(2),
  times(3)
])  
// x * 2 * 3

pipe([
  times(2),
  plus(3),
  times(4)
]) 
// (x * 2 + 3) * 4

pipe([
  times(2),
  subtract(3),
  divide(4)
]) 
// (x * 2 - 3) / 4

Can you implement a pipe() function that will work as the examples stated above?


You can see the full challenge with visuals at this link.