anarinya · Apr 12, 2017
diff --git a/package.json b/package.json
@@ -4,7 +4,7 @@
   "description": "LambdaSchool's JavaScript Mini-Bootcamp Homework 1",
   "main": "index.js",
   "scripts": {
-    "test": "./node_modules/.bin/eslint tests/*.js && ./node_modules/.bin/eslint src/*.js && jest",
+    "test": "eslint tests/*.js && eslint src/*.js && jest",
     "test:watch": "npm test -- --watch"
   },
   "repository": {
@@ -27,6 +27,8 @@
   },
   "dependencies": {
     "babel-preset-es2015": "^6.24.0",
-    "eslint-config-airbnb": "^14.1.0"
+    "eslint-config-airbnb": "^14.1.0",
+    "eslint-plugin-jsx-a11y": "^4.0.0",
+    "eslint-plugin-react": "^6.10.3"
   }
 }
diff --git a/src/arrays.js b/src/arrays.js
@@ -3,38 +3,74 @@
 
 /* eslint-disable no-unused-vars, max-len */
 
+// const each = (elements, cb) => elements.forEach((el, index) => cb(el, index));
 const each = (elements, cb) => {
   // Iterates over a list of elements, yielding each in turn to the `cb` function.
   // This only needs to work with arrays.
   // based off http://underscorejs.org/#each
+  for (let i = 0; i < elements.length; i++) {
+    cb(elements[i], i);
+  }
 };
 
+// const map = (elements, cb) => elements.map(el => cb(el));
 const map = (elements, cb) => {
   // Produces a new array of values by mapping each value in list through a transformation function (iteratee).
   // Return the new array.
+  const arr = [];
+  for (let i = 0; i < elements.length; i++) {
+    arr.push(cb(elements[i], i));
+  }
+  return arr;
 };
 
-const reduce = (elements, cb, memo) => {
+// const reduce = (elements, cb, memo = 0) => elements.reduce((tot, el) => cb(tot, el), memo);
+const reduce = (elements, cb, memo = 0) => {
   // Combine all elements into a single value going from left to right.
   // Elements will be passed one by one into `cb`.
   // `memo` is the starting value.  If `memo` is undefined then make `elements[0]` the initial value.
+  //  const result = arrayMethods.reduce(arr, (memo, num) => (memo + num), 10);
+  let sum = memo;
+
+  for (let i = 0; i < elements.length; i++) {
+    sum = cb(sum, elements[i]);
+  }
+  return sum;
 };
 
+// const find = (elements, cb) => elements.find(el => cb(el));
 const find = (elements, cb) => {
   // Look through each value in `elements` and pass each element to `cb`.
   // If `cb` returns `true` then return that element.
   // Return `undefined` if no elements pass the truth test.
+  let val;
+
+  for (let i = 0; i < elements.length; i++) {
+    if (cb(elements[i])) {
+      val = elements[i];
+      break;
+    }
+    val = undefined;
+  }
+  return val;
 };
 
+// const filter = (elements, cb) => elements.filter(el => cb(el));
 const filter = (elements, cb) => {
   // Similar to `find` but you will return an array of all elements that passed the truth test
   // Return an empty array if no elements pass the truth test
+  const passed = [];
+  for (let i = 0; i < elements.length; i++) {
+    if (cb(elements[i])) passed.push(elements[i]);
+  }
+  return passed;
 };
 
-const flatten = (elements) => {
+const flatten = elements => elements.reduce(
+  (arr, el) => arr.concat(Array.isArray(el) ? flatten(el) : el), []);
   // Flattens a nested array (the nesting can be to any depth).
   // Example: flatten([1, [2], [3, [[4]]]]); => [1, 2, 3, 4];
-};
+
 
 /* eslint-enable no-unused-vars, max-len */
 

diff --git a/src/closure.js b/src/closure.js
@@ -7,17 +7,42 @@ const counter = () => {
   // Example: const newCounter = counter();
   // newCounter(); // 1
   // newCounter(); // 2
+  let count = 0;
+
+  return () => {
+    count += 1;
+    return count;
+  };
 };
 
 const counterFactory = () => {
   // Return an object that has two methods called `increment` and `decrement`.
   // `increment` should increment a counter variable in closure scope and return it.
   // `decrement` should decrement the counter variable and return it.
+  let count = 0;
+
+  return {
+    increment: () => {
+      count += 1;
+      return count;
+    },
+    decrement: () => {
+      count -= 1;
+      return count;
+    },
+  };
 };
 
 const limitFunctionCallCount = (cb, n) => {
   // Should return a function that invokes `cb`.
   // The returned function should only allow `cb` to be invoked `n` times.
+  let count = 0;
+
+  return (...args) => {
+    count += 1;
+    if (count <= n) return cb(...args);
+    return null;
+  };
 };
 
 const cacheFunction = (cb) => {
@@ -27,6 +52,12 @@ const cacheFunction = (cb) => {
   // If the returned function is invoked with arguments that it has already seen
   // then it should return the cached result and not invoke `cb` again.
   // `cb` should only ever be invoked once for a given set of arguments.
+  const cache = {};
+
+  return (x) => {
+    if (!hasOwnProperty.call(cache, x)) cache[x] = cb(x);
+    return cache[x];
+  };
 };
 
 /* eslint-enable no-unused-vars */

diff --git a/src/es6.js b/src/es6.js
@@ -7,50 +7,33 @@
 //----------------
 // const, =>, default parameters, arrow functions default return statements using ()
 
-var food = 'pineapple';
-
-var isMyFavoriteFood = function(food) {
-  food = food || 'thousand-year-old egg'; //This sets a default value if `food` is falsey
-  return food === 'thousand-year-old egg';
-};
-
-var isThisMyFavorite = isMyFavoriteFood(food);
+const food = 'pineapple';
+const isMyFavoriteFood = (food = 'thousand-year-old egg') => food === 'thousand-year-old egg';
+const isThisMyFavorite = isMyFavoriteFood(food);
 
 //----------------
 //const, class, template literals, enhanced object literals (foo: foo, -> foo,)
 
-var User = function(options) {
-  this.username = options.username;
-  this.password = options.password;
-  this.sayHi = function() {
-    return this.username + ' says hello!';
-  };
+class User {
+  constructor(options) {
+    this.username = options.username;
+    this.password = options.password;
+  }
+  sayHi() {
+    return `${this.username} says hello!`;
+  }
 }
 
-var username = 'JavaScriptForever';
-var password = 'password';
-
-var me = new User({
-  username: username,
-  password: password,
-});
+const username = 'JavaScriptForever';
+const password = 'password';
+const me = new User({ username, password });
 
 // ----------------
 // let, const, =>, ... (spread operator)
 
-var addArgs = function () {
-  var sum = 0;
-  for (var i = 0; i < arguments.length; i++) {
-    sum += arguments[i];
-  }
-  return sum;
-};
-
-var argsToCb = function (cb) {
-  var args = Array.prototype.slice.call(arguments);
-  return cb.apply(null, args.splice(1));
-};
+const addArgs = (...args) => args.reduce((sum, num) => sum + num);
+const argsToCb = (cb, ...args) => cb.apply(null, args);
 
-var result = argsToCb(addArgs, 1, 2, 3, 4, 5); //result should be 15
+const result = argsToCb(addArgs, 1, 2, 3, 4, 5); // result should be 15
 
 /* eslint-enable */
diff --git a/src/objects.js b/src/objects.js
@@ -3,38 +3,60 @@
 
 /* eslint-disable no-unused-vars */
 
-const keys = (obj) => {
+const keys = obj => Object.keys(obj);
   // Retrieve all the names of the object's properties.
   // Return the keys as strings in an array.
   // Based on http://underscorejs.org/#keys
-};
 
-const values = (obj) => {
+const values = obj => Object.keys(obj).map(key => obj[key]);
   // Return all of the values of the object's own properties.
   // Ignore functions
   // http://underscorejs.org/#values
-};
 
+// const mapObject = (obj, cb) => Object.keys(obj).map(key => { cb(obj[key]) });
 const mapObject = (obj, cb) => {
   // Like map for arrays, but for objects. Transform the value of each property in turn.
   // http://underscorejs.org/#mapObject
+  const copy = {};
+  const items = keys(obj);
+
+  for (let i = 0, len = items.length; i < len; i++) {
+    copy[items[i]] = cb(obj[items[i]]);
+  }
+  return copy;
 };
 
-const pairs = (obj) => {
+const pairs = obj => Object.keys(obj).map(key => [key, obj[key]]);
   // Convert an object into a list of [key, value] pairs.
   // http://underscorejs.org/#pairs
-};
 
 const invert = (obj) => {
   // Returns a copy of the object where the keys have become the values and the values the keys.
   // Assume that all of the object's values will be unique and string serializable.
   // http://underscorejs.org/#invert
+  const copy = {};
+  const arr = pairs(obj);
+
+  for (let i = 0, len = arr.length; i < len; i++) {
+    copy[arr[i][1]] = arr[i][0];
+  }
+  return copy;
 };
 
 const defaults = (obj, defaultProps) => {
   // Fill in undefined properties that match properties on the `defaultProps` parameter object.
   // Return `obj`.
   // http://underscorejs.org/#defaults
+  const objKeys = pairs(obj);
+  const defKeys = pairs(defaultProps);
+
+  for (let i = 0, len = defKeys.length; i < len; i++) {
+    const key = defKeys[i][0];
+    const val = defKeys[i][1];
+
+    if (!obj[key]) obj[key] = val;
+  }
+  return obj;
 };
 
 /* eslint-enable no-unused-vars */

diff --git a/src/recursion.js b/src/recursion.js
@@ -5,16 +5,44 @@
 const nFibonacci = (n) => {
   // fibonacci sequence: 1 2 3 5 8 13 ...
   // return the nth number in the sequence
+  if (n <= 1) return 1;
+  return nFibonacci(n - 1) + nFibonacci(n - 2);
 };
 
 const nFactorial = (n) => {
   // factorial example: !5 = 5 * 4 * 3 * 2 * 1
   // return the factorial of `n`
+  if (n === 0) return 1;
+  return n * nFactorial(n - 1);
 };
 
 const checkMatchingLeaves = (obj) => {
   // return true if every property on `obj` is the same
   // otherwise return false
+  const values = [];
+
+  const flatten = (set) => {
+    const keys = Object.keys(set);
+
+    for (let i = 0, len = keys.length; i < len; i++) {
+      if (typeof set[keys[i]] !== 'object') {
+        values.push(set[keys[i]]);
+      } else {
+        return flatten(set[keys[i]]);
+      }
+    }
+    return null;
+  };
+
+  const checkVals = (vals) => {
+    for (let i = 0, len = vals.length; i < len; i++) {
+      if (vals[i] !== vals[0]) return false;
+    }
+    return true;
+  };
+
+  flatten(obj);
+  return checkVals(values);
 };
 
 /* eslint-enable no-unused-vars */

diff --git a/src/this.js b/src/this.js
@@ -7,10 +7,15 @@
 class User {
   constructor(options) {
     // set a username and password property on the user object that is created
+    this.username = options.username;
+    this.password = options.password;
   }
   // create a method on the User class called `checkPassword`
   // this method should take in a string and compare it to the object's password property
   // return `true` if they match, otherwise return `false`
+  checkPassword(str) {
+    return this.password === str;
+  }
 }
 
 /* eslint-enable no-useless-constructor */
@@ -23,14 +28,18 @@ const checkPassword = function comparePasswords(passwordToCompare) {
   // use `this` to access the object's `password` property.
   // do not modify this function's parameters
   // note that we use the `function` keyword and not `=>`
+  return this.password === passwordToCompare;
 };
 
 /* eslint-enable no-unused-vars */
 // invoke `checkPassword` on `me` by explicitly setting the `this` context
 // use .call, .apply, and .bind
 
 // .call
+checkPassword.call(me, 'correcthorsebatterystaple');
 
 // .apply
+checkPassword.apply(me, ['correcthorsebatterystaple']);
 
 // .bind
+checkPassword.bind(me)('correcthorsebatterystaple');