Additional solutions

async.js

@@ -61,3 +61,30 @@ function everyXsecsForYsecs(func, interval, duration) {
 //   console.log('This is the end!');
 // }
 // everyXsecsForYsecs(theEnd, 2, 20); // should invoke theEnd function every 2 seconds, for 20 seconds): This is the end!
+
+
+/* CHALLENGE 7 */
+
+function delayCounter(target, wait) {
+  let intervalId;
+  let counter = 0;
+  return function inner() {
+    if (counter === 0) {
+      counter++;
+      intervalId = setInterval(() => console.log(inner()), wait);
+    } else if (counter === target) {
+      clearInterval(intervalId);
+      return counter;
+    } else {
+      return counter++;
+    }
+  }
+}
+
+// UNCOMMENT THESE TO TEST YOUR WORK!
+// const countLogger = delayCounter(3, 1000)
+// countLogger();
+// After 1 second, log 1
+// After 2 seconds, log 2
+// After 3 seconds, log 3
+

callbacks.js

@@ -112,3 +112,21 @@ function multiMap(arrVals, arrCallbacks) {
 // console.log(multiMap(['catfood', 'glue', 'beer'], [function(str) { return str.toUpperCase(); }, function(str) { return str[0].toUpperCase() + str.slice(1).toLowerCase(); }, function(str) { return str + str; }]));
 // should log: { catfood: ['CATFOOD', 'Catfood', 'catfoodcatfood'], glue: ['GLUE', 'Glue', 'glueglue'], beer: ['BEER', 'Beer', 'beerbeer'] }
 
+
+//Extension 7
+function objectFilter(obj, callback) {
+  const newObj = {};
+  for (let key in obj) {
+    if (callback(key) === obj[key]) {
+      newObj[key] = callback(key);
+    }
+  }
+  return newObj;
+}
+
+// const cities = {
+//   London: 'LONDON',
+//   LA: 'Los Angeles',
+//   Paris: 'PARIS',
+// };
+// console.log(objectFilter(cities, city => city.toUpperCase())) // Should log { London: 'LONDON', Paris: 'PARIS'}

closures.js

@@ -112,3 +112,19 @@ const afterCalled = after(3, called);
 function delay(func, wait, ...args) {
   setTimeout(() => func(...args), wait);
 }
+
+// Challenge 8
+function rollCall(names) {
+  return () => {
+    if (!names.length) return console.log('Everyone accounted for');
+    console.log(names.shift());
+  }
+}
+
+// UNCOMMENT THESE TO TEST YOUR WORK!
+// const rollCaller = rollCall(['Victoria', 'Juan', 'Ruth'])
+// rollCaller() // -> Should log 'Victoria'
+// rollCaller() // -> Should log 'Juan'
+// rollCaller() // -> Should log 'Ruth'
+// rollCaller() // -> Should log 'Everyone accounted for'
+

oop.js

@@ -192,3 +192,29 @@ const adminFromFactory = adminFactory("Eva", 5);
 // /********* Uncomment these lines to test your work! *********/
 adminFromFactory.sayType() // -> Logs "I am a Admin"
 adminFromFactory.sharePublicMessage() // -> Logs "Welcome users!"
+
+
+/****************************************************************
+EXTENSION: MIXINS
+****************************************************************/
+
+class Dog {
+  constructor() {
+    this.legs = 4;
+  }
+  speak() {
+    console.log('Woof!');
+  }
+}
+
+const robotSkillsMixin = {
+  skin: 'metal',
+  speak: function () { console.log(`I have ${this.legs} legs and am made of ${this.skin}`) },
+}
+
+let robotFido = new Dog();
+
+robotFido = Object.assign(robotFido, robotSkillsMixin);
+
+// /********* Uncomment these lines to test your work! *********/
+robotFido.speak() // -> Logs "I am made of metal"