added the listing to text

Author: habibasorour

source/ch4_conditionals.ptx

@@ -261,7 +261,7 @@ The <c>switch</c> statement is not used very often, and we recommend you do not
         <title>Exception Handling</title>
 
         <p>
-            In Python, if you want a program to continue running when an error has occurred, you can use <c>try-except</c> blocks to handle exceptions. If you wanted to write a program that asks the user to enter a whole number and then squares that number, you could use the following code to do so:
+            In Python, if you want a program to continue running when an error has occurred, you can use <c>try-except</c> blocks to handle exceptions. If you wanted to write a program that asks the user to enter a whole number and then squares that number, you could use the following code to do so. <xref ref="python-square-input" text="type-global"/> shows the Python code to achieve this.
         </p>
 
         <listing xml:id="python-square-input">
@@ -275,7 +275,7 @@ The <c>switch</c> statement is not used very often, and we recommend you do not
         </listing>
 
         <p>
-            The Java code that would perform the same task is a little more complex and utilizes the <c>Scanner</c> class for input.
+            <xref ref="java-square-input" text="type-global"/> shows the Java code that would perform the same task. It is a little more complex and utilizes the <c>Scanner</c> class for input.
         </p>
         <listing xml:id="java-square-input">
         <program interactive="activecode" language="java">
@@ -298,7 +298,7 @@ The <c>switch</c> statement is not used very often, and we recommend you do not
         </listing>
 
         <p>
-            This code works well, but will end with an exception if the user types anything other than a whole number (such as 12.5 or two). If we wanted to ensure the code will continue to run until the user enters the correct format, we could add <c>try-except</c> (Python) or <c>try-catch</c> (Java) blocks within a <c>while</c> loop that iterates until the user enter the correct code. Adding <c>try-except</c> blocks and a <c>while</c> loop to the Python code will look something like this:
+            This code works well, but will end with an exception if the user types anything other than a whole number (such as 12.5 or two). If we wanted to ensure the code will continue to run until the user enters the correct format, we could add <c>try-except</c> (Python) or <c>try-catch</c> (Java) blocks within a <c>while</c> loop that iterates until the user enter the correct code. <xref ref="python-square-input-exception" text="type-global"/> shows how adding <c>try-except</c> blocks and a <c>while</c> loop to the Python code will look.
         </p>
         <listing xml:id="python-square-input-exception">
         <program interactive="activecode" language="python">
@@ -316,7 +316,7 @@ The <c>switch</c> statement is not used very often, and we recommend you do not
         </listing>
 
         <p>
-            Now that we have Python code that will continuously prompt the user until they enter a whole number, let's look at Java code that accomplishes the same task. Like most other equivalent Java code blocks, this code has a lot of extra bits that are necessary to get working code. 
+            Now that we have Python code that will continuously prompt the user until they enter a whole number, <xref ref="java-square-input-exception" text="type-global"/> shows the Java code that accomplishes the same task. Like most other equivalent Java code blocks, this code has a lot of extra bits that are necessary to get working code.
         </p>
         <listing xml:id="java-square-input-exception">
         <program interactive="activecode" language="java">