--- /dev/null
+(* Copyright (C) 2000, HELM Team.
+ *
+ * This file is part of HELM, an Hypertextual, Electronic
+ * Library of Mathematics, developed at the Computer Science
+ * Department, University of Bologna, Italy.
+ *
+ * HELM 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 2
+ * of the License, or (at your option) any later version.
+ *
+ * HELM 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 HELM; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ *
+ * For details, see the HELM World-Wide-Web page,
+ * http://cs.unibo.it/helm/.
+ *)
+
+(* $Id$ *)
+
+(* This module implements the Query interface to the Coercion Graph *)
+
+type coercion_search_result =
+ (* metasenv, last coercion argument, fully saturated coercion *)
+ (* to apply the coercion it is sufficient to unify the last coercion
+ argument (that is a Meta) with the term to be coerced *)
+ | SomeCoercion of (Cic.metasenv * Cic.term * Cic.term) list
+ | SomeCoercionToTgt of (Cic.metasenv * Cic.term * Cic.term) list
+ | NoCoercion
+ | NotMetaClosed
+ | NotHandled of string Lazy.t
+
+val look_for_coercion :
+ Cic.metasenv -> Cic.substitution -> Cic.context ->
+ Cic.term -> Cic.term -> coercion_search_result
+
+val look_for_coercion' :
+ Cic.metasenv -> Cic.substitution -> Cic.context ->
+ CoercDb.coerc_carr -> CoercDb.coerc_carr -> coercion_search_result
+
+(* checks if term is a constant or
+ * a constant applyed that is marked with (`Class `Coercion) *)
+val is_composite: Cic.term -> bool
+
+val source_of: Cic.term -> Cic.term
+
+val generate_dot_file: unit -> string
+
+(* given the Appl contents returns the argument of the head coercion *)
+val coerced_arg: Cic.term list -> Cic.term option
+
+(* returns: (carr,menv,(saturated coercion,last arg)option,idem) list *)
+val meets :
+ Cic.metasenv -> Cic.substitution -> Cic.context ->
+ CoercDb.coerc_carr -> CoercDb.coerc_carr ->
+ (CoercDb.coerc_carr * Cic.metasenv *
+ (Cic.term * Cic.term) option * (Cic.term * Cic.term) option) list
+