simpler way to handle multiple segments in URI routing for Codeigniter 3.x

I've upgraded from Codeigniter version 2.x to 3.x and noticed that the URI routing behaves differently when passing in multiple segments.

In version 2.x, I was able to pass the following URL variations:

domain.com/function/arg1
domain.com/function/arg1/arg2
domain.com/function/arg1/arg2/arg3

Where $route['function/(:any)'] = 'function/$1' would work for all three URL variations given that my function call is function($arg1, $arg2 = 0, $arg3 = 0) which allows arg2 and arg3 to be optional and be passed in as $1 in the routing rules.

In order for it to work in version 3.x, I find that I have to set up my routing as:

$route['function/(:any)'] = 'function/$1';
$route['function/(:any)/(:any)'] = 'function/$1/$2';
$route['function/(:any)/(:any)/(:any)'] = 'function/$1/$2/$3';

Is there any way I can simplify the routing so that it will pass all remaining segments without having to create separate routing rules for each variation of the number of possible segments?