Notice: Undefined property: WP::$get_query_var

I need help with the following function:

function info_template_redirect() {
	global $wp;
	if ($wp->get_query_var['post_type'] == 'information') {
		if( file_exists( get_stylesheet_directory() . '/single-information.php') ) {
			include( get_stylesheet_directory() . '/single-information.php');
			die();
		}
	}
 }
add_action( 'template_redirect', '_info_template_redirect');

I keep getting the following error in debug mode

Notice: Undefined property: WP::$get_query_var in \wordpress\wp-content\themes\mytheme\functions\widgets.php on line 300

which is the following line of code
if ($wp->get_query_var['post_type'] == 'information') {

What this function should do is to call the template single-information.php for the use for information posts in a widget. But that does not happen.

Here is the function to show the information posts to choose from

function info_get_posts() {

	$postlist = array();
	array_push( $postlist ,array( "value" => 0,"label" => '') );

	$args = array('post_type' => 'information','numberposts' => -1,'post_status' => 'publish' );
	$myposts = get_posts( $args );
	foreach( $myposts as $post ) {
		array_push( $postlist ,array( "value" => $post->ID,"label" => $post->post_title) );
	}
	return $postlist;
}