Code drop from //branches/cupcake/...@124589
diff --git a/src/relation.h b/src/relation.h
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+/* Binary relations.
+ Copyright (C) 2002, 2004 Free Software Foundation, Inc.
+
+ This file is part of Bison, the GNU Compiler Compiler.
+
+ Bison 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, or (at your option)
+ any later version.
+
+ Bison 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 Bison; see the file COPYING. If not, write to
+ the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ Boston, MA 02110-1301, USA. */
+
+
+#ifndef RELATION_H_
+# define RELATION_H_
+
+/* Performing operations on graphs coded as list of adjacency.
+
+ If GRAPH is a relation, then GRAPH[Node] is a list of adjacent
+ nodes, ended with END_NODE. */
+
+#define END_NODE ((relation_node) -1)
+
+typedef size_t relation_node;
+typedef relation_node *relation_nodes;
+typedef relation_nodes *relation;
+
+
+/* Report a relation R that has SIZE vertices. */
+void relation_print (relation r, relation_node size, FILE *out);
+
+/* Compute the transitive closure of the FUNCTION on the relation R
+ with SIZE vertices.
+
+ If R (NODE-1, NODE-2) then on exit FUNCTION[NODE - 1] was extended
+ (unioned) with FUNCTION[NODE - 2]. */
+void relation_digraph (relation r, relation_node size, bitsetv *function);
+
+/* Destructively transpose *R_ARG, of size N. */
+void relation_transpose (relation *R_arg, relation_node n);
+
+#endif /* ! RELATION_H_ */