Cause of "Method name must be a string"
<pre><code>public function run() { 
$this-&gt;step = $this-&gt;$_POST("step", 1);
$this-&gt;xml = new XMLFile();
$common_data = array(
                    'STEPCONTENT' =&gt; $this-&gt;get_step_content(),
                    'STEPNUMBER' =&gt; $this-&gt;step,
                    'STEPTITLE' =&gt; $this-&gt;get_step_title()
                    ); 
echo $this-&gt;parse($this-&gt;common_template, $common_data);
</code></pre>

<p>This gives the exception:</p>

<pre><code>Fatal error: Method name must be a string in
    C:\xampp\htdocs\test\openad\install\InstallOpenAdServer.php on line 674
</code></pre>

<p>Why?</p>
