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    <h1>Conditional Expressions</h1>

    <p>The value of x is <b>5</b><br>
    The value of y is <b>10</b><br>
    The value of n is <b>Fred's Flute</b></p>

<table cellpadding=2 cellspacing=0 border=1>
<tr bgcolor=#eeeeee>
<th>Operator</th>
<th>Test</th>
<th>Result</th>
</tr>

<tr><td><tt><b>eq</b></tt></td>
    <td><tt>if x eq 5</tt></td>
    <td><b>
X is 5
</b></td>
</tr>

<tr><td><tt><b>eq</b></tt></td>
    <td><tt>if x eq 6</tt></td>
    <td><b>
X is not 6</b></td>
</tr>

<tr><td><tt><b>eq</b></tt></td>
    <td><tt>if n eq "Fred's Flute"</tt></td>
    <td><b>
N is "Fred's Flute"
</b></td>
</tr>

<tr><td><tt><b>eq</b></tt></td>
    <td><tt>if n eq "Fred"</tt></td>
    <td><b>

           N is not "Fred"</b></td>
</tr>

<tr><td><tt><b>defined</b></tt></td>
    <td><tt>if x defined</tt></td>
    <td><b>
x is defined
</b></td>
</tr>

<tr><td><tt><b>nil</b></tt></td>
    <td><tt>if x nil</tt></td>
    <td><b>

           x is nonnil</b></td>
</tr>

<tr><td><tt><b>defined</b></tt></td>
    <td><tt>if z defined</tt></td>
    <td><b>
z is defined
</b></td>
</tr>

<tr><td><tt><b>nil</b></tt></td>
    <td><tt>if z nil</tt></td>
    <td><b>
z is nil
</b></td>
</tr>

<tr><td><tt><b>defined</b></tt></td>
    <td><tt>if w defined</tt></td>
    <td><b>

           w is undefined</b></td>
</tr>

<tr><td><tt><b>nil</b></tt></td>
    <td><tt>if w nil</tt></td>
    <td><b>
w is nil
</b></td>
</tr>

</table>















