Undocumented predicates

The following predicates are exported, but not or incorrectly documented.

 is_flat(Arg1)

 is_unflat(Arg1)

 connected_vars(Arg1, Arg2, Arg3, Arg4)

 truncate_unconnected(Arg1, Arg2)

 truncate_unconnected(Arg1)

 is_weakly_generative(Arg1)

 is_strongly_generative(Arg1)

 is_connected(Arg1)

 truncate(Arg1, Arg2, Arg3)

 truncate_r(Arg1, Arg2)

 truncate_r(Arg1)

 truncate_flat_r(Arg1)

 truncate_unconnecting(Arg1)

 truncate_unconnecting(Arg1, Arg2)

 truncate_strongly_generative(Arg1)

 truncate_strongly_generative(Arg1, Arg2)

 truncate_neg_based(Arg1)

 truncate_flat_neg_based(Arg1)

 truncate_facts(Arg1)

 truncate_j(Arg1, Arg2)

 noduplicate_atoms(Arg1)

 noduplicate_atom(Arg1, Arg2)

 select_var_sharing_lits(Arg1, Arg2)

 already_in(Arg1, Arg2, Arg3)