Added 5 tests to show operators. Includes modulus

Author: caleywoods

jskoans.htm

@@ -7,6 +7,7 @@
   <script type="text/javascript" src="support/qunit.js"></script>
   <script type="text/javascript" src="support/koans.js"></script>
   <script type="text/javascript" src="topics/about_asserts.js"></script>
+  <script type="text/javascript" src="topics/about_operators.js"></script>
   <script type="text/javascript" src="topics/about_equality.js"></script>
   <script type="text/javascript" src="topics/about_truthyness.js"></script>
   <script type="text/javascript" src="topics/about_assignment.js"></script>

topics/about_operators.js

@@ -0,0 +1,50 @@
+$(document).ready(function(){
+
+	module("About Operators (topics/about_operators.js)");
+
+  test("addition", function() {
+    var result = 0;
+    //starting i at 0, add i to result and increment i by 1 until i is equal to 5
+    for (var i = 0; i <= 5; i++) {
+      result = result + i;
+    }
+    equals(result, __, "What is the value of result?");
+  });
+
+  test("assignment addition", function() {
+    var result = 0;
+    for (var i = 0; i <=5; i++) {
+      //the code below is just like saying result = result + i; but is more concise
+      result += i;
+    }
+    equals(result, __, "What is the value of result?");
+  });
+
+  test("subtraction", function() {
+    var result = 5;
+    for (var i = 0; i <= 2; i++) {
+      result = result - i;
+    }
+    equals(result, __, "What is the value of result?");
+  });
+
+  test("assignment subtraction", function() {
+    var result = 5;
+    for (var i = 0; i <= 2; i++) {
+      result -= i;
+    }
+    equals(result, __, "What is the value of result?");
+  });
+
+  //Assignment operators are available for multiplication and division as well
+  //let's do one more, the modulo operator, used for showing division remainder
+
+  test("modulus", function() {
+    var result = 10;
+    var x = 5;
+    //again this is exactly the same as result = result % x
+    result %= x;
+    equals(result, __, "What is the value of result?");
+  });
+
+});