bjdixon

memo = function (fn) {
  var cache = {};
  return function () {
    var key = JSON.stringify(this, arguments);
    return cache[key] || (cache[key] = fn.apply(this, arguments));
  }
}

bjdixon

const copyObject = (source) => Object.assign({}, source);

const Stack = () => {
  const array = [];
      
  return {
    push (value) {
      array.push(value);
    },
    pop () {

bjdixon

const Queue = () => {
  let array = [];
  
  return {
    push: (value) => array.push(value),
    pull: () => array.shift(),
    isEmpty: () => !array.length
  };
};

bjdixon

function flatten(a) {
    return a.map(function(val) {
        return (Array.isArray(val)) ? flatten(val) : val;
    });
}

//example usage
var arr = [1, 2, [3, 4], 5, [6, [7, [8]], 9], 10];
var flat = flatten(arr); // [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

bjdixon

function compact(a) {
  return a.reduce(function(memo, x) {
    return x ? memo.concat(x) : memo;
  }, []);
}

bjdixon

function partial (fn) {
    var initialArgs = Array.prototype.slice.call(arguments, 1);
    return function () {
        var remainingArgs = Array.prototype.slice.call(arguments);
        return fn.apply({}, initialArgs.concat(remainingArgs));
    }
}

function findIndex(arr, predicate) {
    var i;

bjdixon

var isBoolean = is('Boolean'),
    isNumber = is('Number'),
    isString = is('String'),
    isObject = is('Object'),
    isArray = is('Array');

function is(type) {
    var fastTypes = ['undefined', 'boolean', 'string', 'number', 'function', 'symbol'];
    if (fastTypes.indexOf(type.toLowerCase()) >= 0) {
        type = type.toLowerCase();

bjdixon

function maybe(fn) {
    return function () {
        var args = Array.prototype.slice.call(arguments);
        if (!args.length) {
            return;
        }
        for (var index = 0, length = args.length; index < length; index += 1) {
            if (args[index] == null) {
                return;
            }

bjdixon

// get the querystring key value pairs
// eg. http:www.example.com/document?a=1&b="2"&c=JavaScript_%D1%88%D0%B5%D0%BB%D0%BB%D1%8B
// will return {a: "1", b: "2", c: "JavaScript_шеллы"}

var params = (function getURLParams(qs) {
    var pairs = {};
    qs.forEach(function(param) {
        var pair = param.split('=');
        pairs[pair[0]] = decodeURIComponent(pair[1].replace(/\"/g, ''));
    });

bjdixon

function findKey(obj, predicate) {
    for (var prop in obj) {
        if(obj.hasOwnProperty( prop ) ) {
            if (predicate(obj[prop])) {
                return prop;
            }
        } 
    }
}