1 /*
2 
3     This file is part of the Maude 2 interpreter.
4 
5     Copyright 1997-2003 SRI International, Menlo Park, CA 94025, USA.
6 
7     This program is free software; you can redistribute it and/or modify
8     it under the terms of the GNU General Public License as published by
9     the Free Software Foundation; either version 2 of the License, or
10     (at your option) any later version.
11 
12     This program is distributed in the hope that it will be useful,
13     but WITHOUT ANY WARRANTY; without even the implied warranty of
14     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15     GNU General Public License for more details.
16 
17     You should have received a copy of the GNU General Public License
18     along with this program; if not, write to the Free Software
19     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
20 
21 */
22 
23 //
24 //	Class for formulae in some propositional logic.
25 //
26 #ifndef _logicFormula_hh_
27 #define _logicFormula_hh_
28 
29 class LogicFormula
30 {
31 public:
32   enum Op
33   {
34     //
35     //	Primitive
36     //
37     PROPOSITION,
38     LTL_TRUE,
39     LTL_FALSE,
40     //
41     //	Unary
42     //
43     NOT,
44     NEXT,
45     //
46     //	Binary
47     //
48     AND,
49     OR,
50     UNTIL,
51     RELEASE
52   };
53 
54   int makeProp(int propIndex);
55   int makeOp(Op op, int firstArg = NONE, int secondArg = NONE);
56 
57   int getProp(int nodeNr) const;
58   Op getOp(int nodeNr) const;
59   int getArg(int nodeNr, int argNr = 0) const;
60   bool isPropositional(int nodeNr) const;
61   /*
62   bool structuallyImplies(const NatSet& now, const NatSet& next, int candidate) const;
63   bool structuallyContradicts(const NatSet& now, const NatSet& next, int candidate) const;
64   bool containsNegation(const NatSet& indexSet, int formulaIndex) const;
65   bool isNegation(int f1, int f2) const;
66   */
67   void dump(ostream& s);
68 
69 private:
70   struct Node
71   {
72     short op;
73     Bool propositional;
74     int args[2];
75   };
76 
77   Vector<Node> nodes;
78 };
79 
80 inline LogicFormula::Op
getOp(int nodeNr) const81 LogicFormula::getOp(int nodeNr) const
82 {
83   return static_cast<Op>(nodes[nodeNr].op);
84 }
85 
86 inline int
getProp(int nodeNr) const87 LogicFormula::getProp(int nodeNr) const
88 {
89   return nodes[nodeNr].args[0];
90 }
91 
92 inline int
getArg(int nodeNr,int argNr) const93 LogicFormula::getArg(int nodeNr, int argNr) const
94 {
95   return nodes[nodeNr].args[argNr];
96 }
97 
98 inline bool
isPropositional(int nodeNr) const99 LogicFormula::isPropositional(int nodeNr) const
100 {
101   return nodes[nodeNr].propositional;
102 }
103 
104 #endif
105