Checking for user permission to a feature in a space but getting WSOD. is spaces api wrong?

AP.txt states:
You can retrieve the active space later in the page load at any point:

// Retrieve the active space, and use it to set the page title.
$space = spaces_get_space();

// Check that the current user can view the spaces_blog feature for this
// space
$space->access_feature('view', 'space_blog');

I get this error in my logs

PHP Fatal error: Call to a member function access_feature() on a non-object

Am I supposed to the load the space in order to access the functions?