(* ************************************************************************* *)
(* *)
(* natural-deduction: a basic proof assistant for natural deduction in *)
(* first-order logic. *)
(* *)
(* Copyright (C) 2026 Eric Johannesson, eric@ericjohannesson.com *)
(* *)
(* This program is free software: you can redistribute it and/or modify *)
(* it under the terms of the GNU General Public License as published by *)
(* the Free Software Foundation, either version 3 of the License, or *)
(* (at your option) any later version. *)
(* *)
(* This program is distributed in the hope that it will be useful, *)
(* but WITHOUT ANY WARRANTY; without even the implied warranty of *)
(* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *)
(* GNU General Public License for more details. *)
(* *)
(* You should have received a copy of the GNU General Public License *)
(* along with this program. If not, see <https://www.gnu.org/licenses/>. *)
(* *)
(* ************************************************************************* *)
| (** The abstract type of definitions and proofs (items). *) |
type t_itm =
|Def_fml of (FML_types.t_fml * FML_types.t_fml)
|Def_prf of (PRF_types.t_prf * PRF_types.t_prf)
|Prf of PRF_types.t_prf
|Comment of string