Assing a set equal to the union of two other sets. 
- Parameters
- 
  
    | this_target | is the index (in this sparse_packobject) of the set being assinged. |  | this_left | is the index (in this sparse_packobject) of the left operand for the union operation. It is OK for this_target and this_left to be the same value. |  | other_right | is the index (in the other sparse_packobject) of the right operand for the union operation. It is OK for this_target and other_right to be the same value. |  | other | is the other sparse_packobject (which may be the same as thissparse_packobject). |  
 
- Checked Assertions
- 
- this_target < n_set_ 
- this_left < n_set_ 
- other_right < other.n_set_ 
- n_pack_ == other.n_pack_ 
 
Definition at line 344 of file sparse_pack.hpp.