Fix interfaces typo

examples/interfaces/interfaces.go

@@ -56,7 +56,7 @@ func main() {
     // The `circle` and `square` struct types both
     // implement the `geometry` interface so we can use
     // instances of
-    // these structs as arguments to `measure.
+    // these structs as arguments to `measure`.
     measure(s)
     measure(c)
 }

examples/interfaces/interfaces.hash

@@ -1,2 +1,2 @@
-853be73c5685a0510da77c22c64727afa7fb0581
+9bafbade1f5effc38be233c3fd12cbdd7c6e226d
-vx8bwC-Bmq
+guxTzcucR-

public/interfaces

@@ -40,7 +40,7 @@ signatures.</p>
             
           </td>
           <td class="code leading">
-	        <a href="http://play.golang.org/p/vx8bwC-Bmq"><img title="Run code" src="play.png" class="run" /></a>
+	        <a href="http://play.golang.org/p/guxTzcucR-"><img title="Run code" src="play.png" class="run" /></a>
             <div class="highlight"><pre><span class="kn">package</span> <span class="nx">main</span>
 </pre></div>
 
@@ -172,7 +172,7 @@ to work on any <code>geometry</code>.</p>
             <p>The <code>circle</code> and <code>square</code> struct types both
 implement the <code>geometry</code> interface so we can use
 instances of
-these structs as arguments to measure.</p>
+these structs as arguments to <code>measure</code>.</p>
 
           </td>
           <td class="code">