is-callable.xml Remove extra dot in refpurpose, examples nits (#4092)

Author: mmalferov

reference/var/functions/is-callable.xml

@@ -4,7 +4,7 @@
  <refnamediv>
   <refname>is_callable</refname>
   <refpurpose>
-   Verify that a value can be called as a function from the current scope.
+   Verify that a value can be called as a function from the current scope
   </refpurpose>
  </refnamediv>
 
@@ -77,42 +77,37 @@
     <programlisting role="php">
 <![CDATA[
 <?php
-//  How to check a variable to see if it can be called
-//  as a function.
+// How to check a variable to see if it can be called
+// as a function.
 
 //
-//  Simple variable containing a function
+// Simple variable containing a function
 //
 
-function someFunction() 
-{
-}
+function someFunction() {}
 
 $functionVariable = 'someFunction';
 
-var_dump(is_callable($functionVariable, false, $callable_name));  // bool(true)
+var_dump(is_callable($functionVariable, false, $callable_name)); // bool(true)
 
-echo $callable_name, "\n";  // someFunction
+echo $callable_name, "\n"; // someFunction
 
 //
-//  Array containing a method
+// Array containing a method
 //
 
-class someClass {
-
-  function someMethod() 
-  {
-  }
-
+class someClass
+{
+    public function someMethod() {}
 }
 
 $anObject = new someClass();
 
-$methodVariable = array($anObject, 'someMethod');
+$methodVariable = [$anObject, 'someMethod'];
 
-var_dump(is_callable($methodVariable, true, $callable_name));  //  bool(true)
+var_dump(is_callable($methodVariable, true, $callable_name)); // bool(true)
 
-echo $callable_name, "\n";  //  someClass::someMethod
+echo $callable_name, "\n"; // someClass::someMethod
 
 ?>
 ]]>
@@ -131,13 +126,16 @@ echo $callable_name, "\n";  //  someClass::someMethod
 class Foo
 {
     public function __construct() {}
+
     public function foo() {}
 }
 
 var_dump(
-    is_callable(array('Foo', '__construct')),
-    is_callable(array('Foo', 'foo'))
+    is_callable(['Foo', '__construct']),
+    is_callable(['Foo', 'foo'])
 );
+
+?>
 ]]>
     </programlisting>
     &example.outputs;