js-under-pressure.js

function doubleInteger(i) {
    return i*2;    
}

function isNumberEven(i) {
    return i%2 === 0;
}

function getFileExtension(i) {
    if(i.indexOf('.') >= 0) {
        var splits = i.split('.');
        return splits[splits.length-1];
    }
    return false;
}


function longestString(i) {
    return longestString2(i, '');
}

function longestString2(i, longest) {
    if(i.length === 0) return newLongest;
    var newLongest = longest;
    var car = i[0];
    var cdr = i.slice[1];
    if(car.length > longest.length && typeof(car) === "string") newLongest = car;
    
    return longestString2(cdr, newLongest);
}


function arraySum(i) {
    if(i.length === 0) return 0;
    var car = i[0];
    var cdr = i.slice(1);
    if(typeof(car) === "object") return arraySum(car) + arraySum(cdr);
    if(typeof(car) === "number") return car + arraySum(cdr);
    return arraySum(cdr); 
}