better error returned if checked is_object

I don't have 'address' field in mysql table and created get_address()...
 
before:
<html><h2>Unhandled Exception</h2>
				<h3>Message:</h3>
				<pre>Call to a member function results() on a non-object</pre>
				<h3>Location:</h3>
				<pre>/var/www/app/laravel/database/eloquent/model.php on line 680</pre>

after:
<html><h2>Unhandled Exception</h2>
				<h3>Message:</h3>
				<pre>Undefined property: CustomerAddress::$address</pre>
				<h3>Location:</h3>
				<pre>/var/www/app/laravel/database/eloquent/model.php on line 678</pre>
				  <h3>Stack Trace:</h3>
				  <pre>#0 /var/www/app/laravel/laravel.php(42): Laravel\Error::native(8, 'Undefined prope...', '/var/www/app...', 678)
#1 /var/www/app/laravel/database/eloquent/model.php(678): Laravel\{closure}(8, 'Undefined prope...', '/var/www/app...', 678, Array)
#2 /var/www/app/laravel/view.php(386) : eval()'d code(61): Laravel\Database\Eloquent\Model->__get('address')
#3 /var/www/app/laravel/view.php(386): eval()
#4 /var/www/app/laravel/view.php(353): Laravel\View->get()
#5 /var/www/app/laravel/view.php(590): Laravel\View->render()
<SNIP>