Good morning! Here's our prompt for today.

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:

1const times = (y) =>  (x) => x * y
2const plus = (y) => (x) => x + y
3const subtract = (y) =>  (x) => x - y
4const divide = (y) => (x) => x / y

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

1pipe([
2  times(2),
3  times(3)
4])  
5// x * 2 * 3
6
7pipe([
8  times(2),
9  plus(3),
10  times(4)
11]) 
12// (x * 2 + 3) * 4
13
14pipe([
15  times(2),
16  subtract(3),
17  divide(4)
18]) 
19// (x * 2 - 3) / 4

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

Try to solve this here or in Interactive Mode.

How do I practice this challenge?

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pipe([

  times(2),

  subtract(3),

  divide(4)

])

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