Question

Here’s the example code I’m struggling with:

function greaterThan(x) {
  return function(y) {
    return y > x;
  };
}

var greaterThanTen = greaterThan(10);
show(greaterThanTen(9));

Is there a way to put it in math terms or follow the flow or something? I don’t know why 10 is x and 9 is y.

Answer 1

In the line:

var greaterThanTen = greaterThan(10);

You are assinging the variable x to the value 10 and then you store the function in the greaterThanTen Variable to be called later. this means that:

greaterThanTen = function(y) {
    return y > 10;
};

So when you do:

greaterThanTen(9);  #y = 9

You are calling:

return 9 > 10;