include <filename> acts as if the contents of the included file were written in the including file
include <..\lib\openscad_xels_lib\ball_bearings.scad>;
--> bear_in_dil
use <filename> imports modules and functions, but does not execute any commands other than those definitions.
use <..\lib\openscad_xels_lib\ball_bearings.scad>;
--> switch_complete(h)