Add sample of logical operators in if statements

Fixes #494

examples/if-else/if-else.go

@@ -19,6 +19,12 @@ func main() {
 		fmt.Println("8 is divisible by 4")
 	}
 
+	// Logical operators like `&&` and `||` are often
+	// useful in conditions.
+	if 7%2 == 0 || 8%2 == 0 {
+		fmt.Println("either 8 or 7 are even")
+	}
+
 	// A statement can precede conditionals; any variables
 	// declared in this statement are available in the current
 	// and all subsequent branches.

examples/if-else/if-else.hash

@@ -1,2 +1,2 @@
-d6a962236fc1296684cd1ffb2d95d131ed84abde
+152124e287cd55e549bc29bcb8693bf260d1b3ab
-U7xcpdutgCJ
+hTOHdmUcUxz

examples/if-else/if-else.sh

@@ -1,6 +1,7 @@
 $ go run if-else.go 
 7 is odd
 8 is divisible by 4
+either 7 or 8 are even
 9 has 1 digit
 
 # There is no [ternary if](https://en.wikipedia.org/wiki/%3F:)

public/if-else

@@ -42,7 +42,7 @@ straight-forward.</p>
             
           </td>
           <td class="code leading">
-            <a href="https://go.dev/play/p/U7xcpdutgCJ"><img title="Run code" src="play.png" class="run" /></a><img title="Copy code" src="clipboard.png" class="copy" />
+            <a href="https://go.dev/play/p/hTOHdmUcUxz"><img title="Run code" src="play.png" class="run" /></a><img title="Copy code" src="clipboard.png" class="copy" />
           <pre class="chroma"><code><span class="line"><span class="cl"><span class="kn">package</span> <span class="nx">main</span></span></span></code></pre>
           </td>
         </tr>
@@ -95,6 +95,20 @@ straight-forward.</p>
           </td>
         </tr>
         
+        <tr>
+          <td class="docs">
+            <p>Logical operators like <code>&amp;&amp;</code> and <code>||</code> are often
+useful in conditions.</p>
+
+          </td>
+          <td class="code leading">
+            
+          <pre class="chroma"><code><span class="line"><span class="cl">    <span class="k">if</span> <span class="mi">7</span><span class="o">%</span><span class="mi">2</span> <span class="o">==</span> <span class="mi">0</span> <span class="o">||</span> <span class="mi">8</span><span class="o">%</span><span class="mi">2</span> <span class="o">==</span> <span class="mi">0</span> <span class="p">{</span>
+</span></span><span class="line"><span class="cl">        <span class="nx">fmt</span><span class="p">.</span><span class="nf">Println</span><span class="p">(</span><span class="s">&#34;either 8 or 7 are even&#34;</span><span class="p">)</span>
+</span></span><span class="line"><span class="cl">    <span class="p">}</span></span></span></code></pre>
+          </td>
+        </tr>
+        
         <tr>
           <td class="docs">
             <p>A statement can precede conditionals; any variables
@@ -140,6 +154,7 @@ in Go, but that the braces are required.</p>
           <pre class="chroma"><code><span class="line"><span class="cl"><span class="gp">$</span> go run if-else.go 
 </span></span><span class="line"><span class="cl"><span class="go">7 is odd
 </span></span></span><span class="line"><span class="cl"><span class="go">8 is divisible by 4
+</span></span></span><span class="line"><span class="cl"><span class="go">either 7 or 8 are even
 </span></span></span><span class="line"><span class="cl"><span class="go">9 has 1 digit</span></span></span></code></pre>
           </td>
         </tr>
@@ -172,7 +187,7 @@ for basic conditions.</p>
     </div>
     <script>
       var codeLines = [];
-      codeLines.push('');codeLines.push('package main\u000A');codeLines.push('import \"fmt\"\u000A');codeLines.push('func main() {\u000A');codeLines.push('    if 7%2 \u003D\u003D 0 {\u000A        fmt.Println(\"7 is even\")\u000A    } else {\u000A        fmt.Println(\"7 is odd\")\u000A    }\u000A');codeLines.push('    if 8%4 \u003D\u003D 0 {\u000A        fmt.Println(\"8 is divisible by 4\")\u000A    }\u000A');codeLines.push('    if num :\u003D 9; num \u003C 0 {\u000A        fmt.Println(num, \"is negative\")\u000A    } else if num \u003C 10 {\u000A        fmt.Println(num, \"has 1 digit\")\u000A    } else {\u000A        fmt.Println(num, \"has multiple digits\")\u000A    }\u000A}\u000A');codeLines.push('');codeLines.push('');codeLines.push('');
+      codeLines.push('');codeLines.push('package main\u000A');codeLines.push('import \"fmt\"\u000A');codeLines.push('func main() {\u000A');codeLines.push('    if 7%2 \u003D\u003D 0 {\u000A        fmt.Println(\"7 is even\")\u000A    } else {\u000A        fmt.Println(\"7 is odd\")\u000A    }\u000A');codeLines.push('    if 8%4 \u003D\u003D 0 {\u000A        fmt.Println(\"8 is divisible by 4\")\u000A    }\u000A');codeLines.push('    if 7%2 \u003D\u003D 0 || 8%2 \u003D\u003D 0 {\u000A        fmt.Println(\"either 8 or 7 are even\")\u000A    }\u000A');codeLines.push('    if num :\u003D 9; num \u003C 0 {\u000A        fmt.Println(num, \"is negative\")\u000A    } else if num \u003C 10 {\u000A        fmt.Println(num, \"has 1 digit\")\u000A    } else {\u000A        fmt.Println(num, \"has multiple digits\")\u000A    }\u000A}\u000A');codeLines.push('');codeLines.push('');codeLines.push('');
     </script>
     <script src="site.js" async></script>
   </body>