get_extended() WordPress Function

function get_extended( $post ) {
	// Match the new style more links.
	if ( preg_match( '/<!--more(.*?)?-->/', $post, $matches ) ) {
		list($main, $extended) = explode( $matches[0], $post, 2 );
		$more_text             = $matches[1];
	} else {
		$main      = $post;
		$extended  = '';
		$more_text = '';
	}

	// Leading and trailing whitespace.
	$main      = preg_replace( '/^[\s]*(.*)[\s]*$/', '\\1', $main );
	$extended  = preg_replace( '/^[\s]*(.*)[\s]*$/', '\\1', $extended );
	$more_text = preg_replace( '/^[\s]*(.*)[\s]*$/', '\\1', $more_text );

	return array(
		'main'      => $main,
		'extended'  => $extended,
		'more_text' => $more_text,
	);
}