Undocumented predicates
The following predicates are exported, but not or incorrectly documented.
-  solve(Arg1, Arg2, Arg3)
-  solve_once(Arg1, Arg2, Arg3)
-  failed_proof(Arg1)
-  prooftrees(Arg1, Arg2, Arg3)
-  proof_close(Arg1, Arg2)
-  prove1(Arg1, Arg2)
-  prove3(Arg1, Arg2)
-  prove4(Arg1, Arg2, Arg3)
-  prove5(Arg1, Arg2)
-  proof_path(Arg1, Arg2, Arg3, Arg4)
-  set_proof_depth
-  t_interpreter(Arg1, Arg2)
-  ip_part1(Arg1, Arg2)
-  ip_part2(Arg1, Arg2, Arg3)