fix(challenges): Improve description in existing object challenges

seed/challenges/02-javascript-algorithms-and-data-structures/basic-javascript.json

@@ -1089,8 +1089,8 @@
         "In the <dfn>goodStr</dfn> above, you can use both quotes safely by using the backslash <code>\\</code> as an escape character.",
         "<strong>Note</strong><br/>The backslash <code>\\</code> should not be be confused with the forward slash <code>/</code>. They do not do the same thing.",
         "<hr>",
-        "Change the provided string to a string with single quotes at the beginning and end and no escape characters.",  
-        "Right now, the <code>&#60;a&#62;</code> tag in the string uses double quotes everywhere. You will need to change the outer quotes to single quotes so you can remove the escape characters."   
+        "Change the provided string to a string with single quotes at the beginning and end and no escape characters.",
+        "Right now, the <code>&#60;a&#62;</code> tag in the string uses double quotes everywhere. You will need to change the outer quotes to single quotes so you can remove the escape characters."
       ],
       "releasedOn": "January 1, 2016",
       "challengeSeed": [
@@ -2697,8 +2697,8 @@
       ],
       "type": "waypoint",
       "challengeType": 1,
-      "translations": {}      
-    },    
+      "translations": {}
+    },
     {
       "id": "56533eb9ac21ba0edf2244c3",
       "title": "Assignment with a Returned Value",
@@ -4229,9 +4229,12 @@
       "description": [
         "You may have heard the term <code>object</code> before.",
         "Objects are similar to <code>arrays</code>, except that instead of using indexes to access and modify their data, you access the data in objects through what are called <code>properties</code>.",
-        "Here's a sample object:",
-        "<blockquote>var cat = {<br>  \"name\": \"Whiskers\",<br>  \"legs\": 4,<br>  \"tails\": 1,<br>  \"enemies\": [\"Water\", \"Dogs\"]<br>};</blockquote>",
         "Objects are useful for storing data in a structured way, and can represent real world objects, like a cat.",
+        "Here's a sample cat object:",
+        "<blockquote>var cat = {<br>  \"name\": \"Whiskers\",<br>  \"legs\": 4,<br>  \"tails\": 1,<br>  \"enemies\": [\"Water\", \"Dogs\"]<br>};</blockquote>",
+        "In this example, all the properties are stored as strings, such as - <code>\"name\"</code>, <code>\"legs\"</code>, and <code>\"tails\"</code>. However, you can also use numbers as properties. You can even omit the quotes for single-word string properties, as follows:",
+        "<blockquote>var anotherObject = {<br>  make: \"Ford\",<br>  5: \"five\",<br>  \"model\": \"focus\"<br>};</blockquote>",
+        "However, if your object has any non-string properties, JavaScript will automatically typecast them as strings.",
         "<hr>",
         "Make an object that represents a dog called <code>myDog</code> which contains the properties <code>\"name\"</code> (a string), <code>\"legs\"</code>, <code>\"tails\"</code> and <code>\"friends\"</code>.",
         "You can set these object properties to whatever values you want, as long <code>\"name\"</code> is a string, <code>\"legs\"</code> and <code>\"tails\"</code> are numbers, and <code>\"friends\"</code> is an array."
@@ -4348,8 +4351,9 @@
       "title": "Accessing Object Properties with Bracket Notation",
       "description": [
         "The second way to access the properties of an object is bracket notation (<code>[]</code>). If the property of the object you are trying to access has a space in its name, you will need to use bracket notation.",
+        "However, you can still use bracket notation on object properties without spaces.",
         "Here is a sample of using bracket notation to read an object's property:",
-        "<blockquote>var myObj = {<br>  \"Space Name\": \"Kirk\",<br>  \"More Space\": \"Spock\"<br>};<br>myObj[\"Space Name\"]; // Kirk<br>myObj['More Space']; // Spock</blockquote>",
+        "<blockquote>var myObj = {<br>  \"Space Name\": \"Kirk\",<br>  \"More Space\": \"Spock\",<br>  \"NoSpace\": \"USS Enterprise\"<br>};<br>myObj[\"Space Name\"]; // Kirk<br>myObj['More Space']; // Spock<br>myObj[\"NoSpace\"];    // USS Enterprise</blockquote>",
         "Note that property names with spaces in them must be in quotes (single or double).",
         "<hr>",
         "Read the values of the properties <code>\"an entree\"</code> and <code>\"the drink\"</code> of <code>testObj</code> using bracket notation and assign them to <code>entreeValue</code> and <code>drinkValue</code> respectively."
@@ -4401,11 +4405,11 @@
       "id": "56533eb9ac21ba0edf2244c9",
       "title": "Accessing Object Properties with Variables",
       "description": [
-        "Another use of bracket notation on objects is to use a variable to access a property. This can be very useful for iterating through lists of the object properties or for doing the lookup.",
+        "Another use of bracket notation on objects is to access a property which is stored as the value of a variable. This can be very useful for iterating through an object's properties or when accessing a lookup table.",
         "Here is an example of using a variable to access a property:",
-        "<blockquote>var someProp = \"propName\";<br>var myObj = {<br>  propName: \"Some Value\"<br >};<br>myObj[someProp]; // \"Some Value\"</blockquote>",
-        "Here is one more:",
-        "<blockquote>var myDog = \"Hunter\";<br>var dogs = {<br>  Fido: \"Mutt\",\n  Hunter: \"Doberman\",\n  Snoopie: \"Beagle\"<br >};<br>var breed = dogs[myDog];<br>console.log(breed);// \"Doberman\"</blockquote>",
+        "<blockquote>var dogs = {<br>  Fido: \"Mutt\",\n  Hunter: \"Doberman\",\n  Snoopie: \"Beagle\"<br>};<br>var myDog = \"Hunter\";<br>var myBreed = dogs[myDog];<br>console.log(myBreed); // \"Doberman\"</blockquote>",
+        "Another way you can use this concept is when the property's name is collected dynamically during the program execution, as follows:",
+        "<blockquote>var someObj = {<br>  propName: \"John\"<br>};<br>function propPrefix(str) {<br>  var s = \"prop\";<br>  return s + str;<br>}<br>var someProp = propPrefix(\"Name\"); // someProp now holds the value 'propName'<br>console.log(obj[someProp]); // \"John\"</blockquote>",
         "Note that we  do <em>not</em> use quotes around the variable name when using it to access the property because we are using the <em>value</em> of the variable, not the <em>name</em>.",
         "<hr>",
         "Use the <code>playerNumber</code> variable to look up player <code>16</code> in <code>testObj</code> using bracket notation. Then assign that name to the <code>player</code> variable."