finished

app.js

@@ -1,28 +1,39 @@
 /* The four rules for 'this';
 * in your own words. explain the four rules for the "this" keyword below.
-* 1. 
-* 2. 
-* 3. 
-* 4. 
+* 1. whenever this is in the global scope, this will point to the window object
+* 2. if a function is called before a dot, that object before the dot is what this points to.
+* 3. when this is used inside a constructor function it refers to the specific new object that is made each time.
+* 4. when the call or apply methods are used this becomes explicitly defined, it points to the objects passed into those methods.
 * write out a code example of each explanation above
 */
 
 // First Rule
-
+const Vehicle = function (traits) {
+  this.make = traits.make;
+  this.size = traits.size;
+};
+const camry = new Vehicle({make: 'toyota', size: 'sedan'});
+camry.message = function () { return `beep beep, i am a ${this.size}`; }
+console.log(camry.message());
+camryBeep = camry.message;
+console.log(camryBeep());
 // Second Rule
-
+Vehicle.prototype.message = function () { return `beep beep, i am a ${this.size}`; }
+console.log(camry.message());
 // Third Rule
-
+const tundra = new Vehicle ({make: 'toyota', size: 'truck'});
+console.log(tundra.message());
 // Fourth Rule * you may want to use your third rule's example to accomplish this
-
-// explain closure 
-
+console.log(camryBeep.call(tundra));
+// explain closure
+//closure is when a variable is declared inside the scope of one function but can be accessed by other functions by calling that function that contains it
 function foo () {
-  console.log(this); // what does this point to?
+  console.log(this); // what does this point to? The global window
 };
 
 const counterFunction = () => {
   // this code is broken. figure out why, and tell us where the closure is when you fix it
+  let count = 0; // this count variable was not declared. it could not be declared inside changeCount because count must be accessed at total.
   const changeCount = (value) => {
     count += value;
   };
@@ -52,16 +63,41 @@ console.log(counter.total());
   // your options object should have "make", "model", "year" properties on it
   // assign these properties you pass in with options to the constructors 'this' object.
   // add a speak() method to your object that when called will log out the car's make model and year.
+// function Car(options) {
+//   this.make = options.make,
+//   this.model = options.model,
+//   this.year = options.year
+//   this.speak = function () { return`${this.make} ${this.model} ${this.year}`;}
+// }
+
 
 // when you're done un comment the next few lines and run the file here in node `node app.js`.
 
 // const herby = new Car({make: 'Volkswagen', model: 'Beetle', year: '1963'});
 // console.log(herby.speak());
 // const goldfinger = new Car({make: 'Aston Martin', model: 'DB5', year: '1964'});
 // console.log(goldfinger.speak());
+//
 
 
-// once you get done with this, redo it all using the class keyword and a constructor function. 
+// once you get done with this, redo it all using the class keyword and a constructor function.
+class Car {
+  constructor (make, model, year) {
+    this.make = make;
+    this.model = model;
+    this.year = year;
+  }
+
+}
+Car.prototype.speak = function() {
+  return `${this.make} ${this.model} ${this.year}`
+}
+const herby = new Car('Volkswagen', 'Beetle', '1963');
+console.log(herby.make);
+console.log(herby.speak());
+const goldfinger = new Car('Aston Martin', 'DB5', '1964');
+console.log(goldfinger.speak());
+
 
 // extra credit
 
@@ -75,7 +111,9 @@ while(n >= 1) {
 }
 // write a function called countDown that does the exact same thing as above, but calls itself until it can't anymore.
   // hint-> your base case will look like the logic in the while loop.
-
-
-
-
+  const counting = (number) => {
+    console.log(number);
+    number--;
+    if (number >= 1) counting(number);
+  };
+  counting(10);