1 /*
2 
3     This file is part of the Maude 2 interpreter.
4 
5     Copyright 1997-2008 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 //	Abstract base class for the accumulation and simultaneous solution of subproblems during unification.
25 //
26 #ifndef _unificationSubproblem_hh_
27 #define _unificationSubproblem_hh_
28 
29 class UnificationSubproblem
30 {
31 public:
~UnificationSubproblem()32   virtual ~UnificationSubproblem() {}  // deep
33 
addUnification(DagNode * lhs,DagNode * rhs,bool marked,UnificationContext & solution)34   virtual void addUnification(DagNode* lhs, DagNode* rhs, bool marked, UnificationContext& solution) { CantHappen("Not implemented " << lhs << " vs " << rhs); }
solve(bool findFirst,UnificationContext & solution,PendingUnificationStack & pending)35   virtual bool solve(bool findFirst, UnificationContext& solution, PendingUnificationStack& pending) { CantHappen("Not implemented"); return false; }
36 
37 #ifdef DUMP
dump(ostream & s,const VariableInfo & variableInfo,int indentLevel=0)38   virtual void dump(ostream& s,
39 		    const VariableInfo& variableInfo,
40 		    int indentLevel = 0) {}  // HACK
41 #endif
42 };
43 
44 #endif
45