Finished

calculator.js

@@ -6,60 +6,114 @@
  * @return {object} `calculator` object that can be used
  */
 
+function calculatorModule(memory, total) {
+    let _total = 0;
+    let _memory = 0;
+
+    return {
+     load: load,
+     getTotal: getTotal,
+     add: add,
+     subtract: subtract,
+     multiply: multiply, 
+     divide: divide,  
+     recallMemory: recallMemory,
+     saveMemory: saveMemory,
+     clearMemory: clearMemory,
+    }
 
   /**
    * sets the `total` to the number passed in
    * @param  { Number } x
    * @return { Number }    current total
    */
 
+   function load(x) {
+
+        validate(x);
+        _total = x;
+        return _total;
+   }
 
   /**
    * Return the value of `total`
    * @return { Number }
    */
 
+   function getTotal() {
+       return _total;
+   }
 
   /**
    * Sums the value passed in with `total`
    * @param { Number } x
    */
 
-
+    function add(x) {
+        validate(x);
+        _total += x;
+    }
   /**
    * Subtracts the value passed in from `total`
    * @param  { Number } x
    */
 
+    function subtract(x) {
+        validate(x);
+        _total -= x;
+    }
 
   /**
    * Multiplies the value by `total`
    * @param  { Number } x
    */
-
+    function multiply(x) {
+        validate(x);
+        _total *= x;
+    }
 
   /**
    * Divides the value passing in by `total`
    * @param  { Number } x
    */
 
+    function divide(x) {
+        validate(x);
+        _total /= x;
+    }
 
   /**
    * Return the value stored at `memory`
    * @return { Number }
    */
 
+   function recallMemory() {
+       return _memory;
+   }
 
   /**
    * Stores the value of `total` to `memory`
    */
 
+   function saveMemory() {
+       _memory = _total;
+   }
 
   /**
    * Clear the value stored at `memory`
    */
 
+   function clearMemory() {
+       _memory = 0;
+   }
+
   /**
    * Validation
    */
 
+   function validate(x) {
+       if (typeof x !== 'number') {
+          throw new Error();
+       }
+   }
+}