Only variable should be passed by referenced in Magento problem

In order to see the path to template in generated html source code for debuggin purposes I used the following code snippet in the

app/code/core/Mage/Core/Block/Template.php

/**
 * Render block
 *
 * @return string
 */
public function renderView()
{
    $this->setScriptPath(Mage::getBaseDir('design'));
    $showDebug = true;
    if (!$showDebug) {
        $html = $this->fetchView($this->getTemplateFile());
    }
    else {
        $template = $this->getTemplateFile();
        $tagName = 'template_'.current(explode('.',end(explode('/',$template))));
        $html = '<'.$tagName.'><!-- '.$template.' -->';
        $html .= $this->fetchView($template);
        $html .= '<!--/ '.$template.' --></'.$tagName.'>';
    }
    return $html;
}

but now in the error logs I see the following: 2010-12-13T21:55:35+00:00 ERR (3): Strict Notice: Onl开发者_JS百科y variables should be passed by reference in /app/code/core/Mage/Core/Block/Template.php on line 245

How should this be referenced in order to avoid this error?

Pretty sure your problem is this line

$tagName = 'template_'.current(explode('.',end(explode('/',$template))));

The end and current methods accept an array variable as a paramater, passed by reference. You're passing the result of a function call, which PHP doesn't like. Assuming that snippet is trying to get an extension-less template name, try this instead

$parts  = pathinfo($template);
$tagName    = $parts['filename']; 

Install the Developer Toolbar extension instead. Or turn on Template Hints from the Admin.