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 // Base class for ACU stripper-collector left hand side automata.
25 //
26 #ifndef _ACU_CollectorLhsAutomaton_hh_
27 #define _ACU_CollectorLhsAutomaton_hh_
28 #include "ACU_LhsAutomaton.hh"
29
30 class ACU_CollectorLhsAutomaton : public ACU_LhsAutomaton
31 {
32 NO_COPYING(ACU_CollectorLhsAutomaton);
33
34 public:
35 ACU_CollectorLhsAutomaton(ACU_Symbol* symbol,
36 bool matchAtTop,
37 bool collapsePossible,
38 int nrVariables,
39 VariableTerm* collector);
40
41 #ifdef DUMP
42 void dump(ostream& s, const VariableInfo& variableInfo, int indentLevel);
43 #endif
44
45 protected:
46 bool collectorFree(Substitution& solution) const;
47 bool collect(int stripped, ACU_DagNode* subject, Substitution& solution) const;
48 bool collect(ACU_Stack& stripped, // destroyed
49 ACU_TreeDagNode* subject,
50 Substitution& solution) const;
51 void collapse(Substitution& solution) const;
52
53 private:
54 //
55 // The stripper variable/automaton/term in the derived class
56 // strips off one argument.
57 // The collector variable collects all the other arguments.
58 //
59 const int collectorVarIndex;
60 //
61 // The collector sort must be unbounded. If it is the error sort
62 // or the unique maximal sort of an error free component we set
63 // it to 0 to switch off sort checks since they should always succeed.
64 //
65 const Sort* collectorSort;
66 };
67
68 inline bool
collectorFree(Substitution & solution) const69 ACU_CollectorLhsAutomaton::collectorFree(Substitution& solution) const
70 {
71 return solution.value(collectorVarIndex) == 0;
72 }
73
74 inline void
collapse(Substitution & solution) const75 ACU_CollectorLhsAutomaton::collapse(Substitution& solution) const
76 {
77 solution.bind(collectorVarIndex, getSymbol()->getIdentityDag());
78 }
79
80 #endif
81