functional.js

function countIf(listOfNames, condition) {
    var i, name, count = 0;

    for(i = 0; i < listOfNames.length; i++) {
        name = listOfNames[i];
        if (condition(name)) {
            count = count + 1;
        }
    }
    return count;
}


var myNames = ["erick", "nicole", "niko", "zola"];

function hasLengthGreaterThan(someLength) {
    return function (x) {
        return (x.length > someLength)
    }
}

var r1 = countIf(myNames, hasLengthGreaterThan(4))

console.log(r1)

function startsWith(someLetter) {
    return function (x) {
        return (x.indexOf(someLetter) == 0)
    }
}

var startsWithN = startsWith("n")
var startsWithS = startsWith("s")
var startsWithE = startsWith("e")

var r2 = countIf(myNames, startsWithN)

console.log(r2)

function compose(f, g) {
    return function (x) {
        return f(g(x))
    }
}

var exp_sin = compose(Math.sin, Math.exp)

console.log(exp_sin(3))

var startsWithNandIsGreaterThan4 = compose(startsWith("n"), hasLengthGreaterThan(4))