gerrit.simantics Code Review - simantics/platform.git/blob

   1 package org.simantics.scl.compiler.internal.parsing.parser;
   2
   3 import java.io.Reader;
   4 import java.util.ArrayList;
   5 import java.util.Arrays;
   6 import java.util.List;
   7
   8 import org.simantics.scl.compiler.common.exceptions.InternalCompilerError;
   9 import org.simantics.scl.compiler.common.precedence.Associativity;
  10 import org.simantics.scl.compiler.common.precedence.Precedence;
  11 import org.simantics.scl.compiler.compilation.CompilationContext;
  12 import org.simantics.scl.compiler.constants.CharacterConstant;
  13 import org.simantics.scl.compiler.constants.StringConstant;
  14 import org.simantics.scl.compiler.elaboration.equation.EqBasic;
  15 import org.simantics.scl.compiler.elaboration.equation.EqGuard;
  16 import org.simantics.scl.compiler.elaboration.equation.Equation;
  17 import org.simantics.scl.compiler.elaboration.expressions.Case;
  18 import org.simantics.scl.compiler.elaboration.expressions.EApply;
  19 import org.simantics.scl.compiler.elaboration.expressions.EAsPattern;
  20 import org.simantics.scl.compiler.elaboration.expressions.EBinary;
  21 import org.simantics.scl.compiler.elaboration.expressions.EBinaryRightSide;
  22 import org.simantics.scl.compiler.elaboration.expressions.EBlock;
  23 import org.simantics.scl.compiler.elaboration.expressions.EConstant;
  24 import org.simantics.scl.compiler.elaboration.expressions.EEnforce;
  25 import org.simantics.scl.compiler.elaboration.expressions.EEquations;
  26 import org.simantics.scl.compiler.elaboration.expressions.EFieldAccess;
  27 import org.simantics.scl.compiler.elaboration.expressions.EIf;
  28 import org.simantics.scl.compiler.elaboration.expressions.EIntegerLiteral;
  29 import org.simantics.scl.compiler.elaboration.expressions.ELambda;
  30 import org.simantics.scl.compiler.elaboration.expressions.EListComprehension;
  31 import org.simantics.scl.compiler.elaboration.expressions.EListLiteral;
  32 import org.simantics.scl.compiler.elaboration.expressions.ELiteral;
  33 import org.simantics.scl.compiler.elaboration.expressions.EMatch;
  34 import org.simantics.scl.compiler.elaboration.expressions.ERange;
  35 import org.simantics.scl.compiler.elaboration.expressions.ERealLiteral;
  36 import org.simantics.scl.compiler.elaboration.expressions.ERecord;
  37 import org.simantics.scl.compiler.elaboration.expressions.ESelect;
  38 import org.simantics.scl.compiler.elaboration.expressions.ESimpleLambda;
  39 import org.simantics.scl.compiler.elaboration.expressions.EStringLiteral;
  40 import org.simantics.scl.compiler.elaboration.expressions.ETransformation;
  41 import org.simantics.scl.compiler.elaboration.expressions.ETypeAnnotation;
  42 import org.simantics.scl.compiler.elaboration.expressions.EVar;
  43 import org.simantics.scl.compiler.elaboration.expressions.EVariable;
  44 import org.simantics.scl.compiler.elaboration.expressions.EViewPattern;
  45 import org.simantics.scl.compiler.elaboration.expressions.Expression;
  46 import org.simantics.scl.compiler.elaboration.expressions.GuardedExpression;
  47 import org.simantics.scl.compiler.elaboration.expressions.GuardedExpressionGroup;
  48 import org.simantics.scl.compiler.elaboration.expressions.Variable;
  49 import org.simantics.scl.compiler.elaboration.expressions.accessor.ExpressionAccessor;
  50 import org.simantics.scl.compiler.elaboration.expressions.accessor.FieldAccessor;
  51 import org.simantics.scl.compiler.elaboration.expressions.accessor.IdAccessor;
  52 import org.simantics.scl.compiler.elaboration.expressions.accessor.StringAccessor;
  53 import org.simantics.scl.compiler.elaboration.expressions.block.BindStatement;
  54 import org.simantics.scl.compiler.elaboration.expressions.block.CHRStatement;
  55 import org.simantics.scl.compiler.elaboration.expressions.block.ConstraintStatement;
  56 import org.simantics.scl.compiler.elaboration.expressions.block.GuardStatement;
  57 import org.simantics.scl.compiler.elaboration.expressions.block.IncludeStatement;
  58 import org.simantics.scl.compiler.elaboration.expressions.block.LetStatement;
  59 import org.simantics.scl.compiler.elaboration.expressions.block.RuleStatement;
  60 import org.simantics.scl.compiler.elaboration.expressions.block.Statement;
  61 import org.simantics.scl.compiler.elaboration.expressions.list.ListAssignment;
  62 import org.simantics.scl.compiler.elaboration.expressions.list.ListGenerator;
  63 import org.simantics.scl.compiler.elaboration.expressions.list.ListGuard;
  64 import org.simantics.scl.compiler.elaboration.expressions.list.ListQualifier;
  65 import org.simantics.scl.compiler.elaboration.expressions.list.ListSeq;
  66 import org.simantics.scl.compiler.elaboration.expressions.list.ListThen;
  67 import org.simantics.scl.compiler.elaboration.expressions.records.FieldAssignment;
  68 import org.simantics.scl.compiler.elaboration.java.Builtins;
  69 import org.simantics.scl.compiler.elaboration.query.QAlternative;
  70 import org.simantics.scl.compiler.elaboration.query.QConjunction;
  71 import org.simantics.scl.compiler.elaboration.query.QDisjunction;
  72 import org.simantics.scl.compiler.elaboration.query.QNegation;
  73 import org.simantics.scl.compiler.elaboration.query.Query;
  74 import org.simantics.scl.compiler.elaboration.query.pre.QPreBinds;
  75 import org.simantics.scl.compiler.elaboration.query.pre.QPreEquals;
  76 import org.simantics.scl.compiler.elaboration.query.pre.QPreGuard;
  77 import org.simantics.scl.compiler.errors.Locations;
  78 import org.simantics.scl.compiler.internal.header.ModuleHeader;
  79 import org.simantics.scl.compiler.internal.parsing.Symbol;
  80 import org.simantics.scl.compiler.internal.parsing.Token;
  81 import org.simantics.scl.compiler.internal.parsing.declarations.ConstructorAst;
  82 import org.simantics.scl.compiler.internal.parsing.declarations.DAnnotationAst;
  83 import org.simantics.scl.compiler.internal.parsing.declarations.DClassAst;
  84 import org.simantics.scl.compiler.internal.parsing.declarations.DDataAst;
  85 import org.simantics.scl.compiler.internal.parsing.declarations.DDerivingInstanceAst;
  86 import org.simantics.scl.compiler.internal.parsing.declarations.DDocumentationAst;
  87 import org.simantics.scl.compiler.internal.parsing.declarations.DEffectAst;
  88 import org.simantics.scl.compiler.internal.parsing.declarations.DFixityAst;
  89 import org.simantics.scl.compiler.internal.parsing.declarations.DImportJavaAst;
  90 import org.simantics.scl.compiler.internal.parsing.declarations.DInstanceAst;
  91 import org.simantics.scl.compiler.internal.parsing.declarations.DMappingRelationAst;
  92 import org.simantics.scl.compiler.internal.parsing.declarations.DRelationAst;
  93 import org.simantics.scl.compiler.internal.parsing.declarations.DRuleAst;
  94 import org.simantics.scl.compiler.internal.parsing.declarations.DRulesetAst;
  95 import org.simantics.scl.compiler.internal.parsing.declarations.DTypeAst;
  96 import org.simantics.scl.compiler.internal.parsing.declarations.DValueAst;
  97 import org.simantics.scl.compiler.internal.parsing.declarations.DValueTypeAst;
  98 import org.simantics.scl.compiler.internal.parsing.declarations.DeclarationAst;
  99 import org.simantics.scl.compiler.internal.parsing.declarations.FieldDescription;
 100 import org.simantics.scl.compiler.internal.parsing.declarations.FundepAst;
 101 import org.simantics.scl.compiler.internal.parsing.exceptions.SCLSyntaxErrorException;
 102 import org.simantics.scl.compiler.internal.parsing.types.TApplyAst;
 103 import org.simantics.scl.compiler.internal.parsing.types.TEffectAst;
 104 import org.simantics.scl.compiler.internal.parsing.types.TForAllAst;
 105 import org.simantics.scl.compiler.internal.parsing.types.TFunctionAst;
 106 import org.simantics.scl.compiler.internal.parsing.types.TListAst;
 107 import org.simantics.scl.compiler.internal.parsing.types.TPredAst;
 108 import org.simantics.scl.compiler.internal.parsing.types.TTupleAst;
 109 import org.simantics.scl.compiler.internal.parsing.types.TVarAst;
 110 import org.simantics.scl.compiler.internal.parsing.types.TypeAst;
 111 import org.simantics.scl.compiler.module.ImportDeclaration;
 112 import org.simantics.scl.compiler.types.Types;
 113
 114
 115 public class SCLParserImpl extends SCLParser {
 116
 117     private final SCLPostLexer lexer;
 118     private SCLParserOptions options;
 119     private CompilationContext context;
 120
 121     public SCLParserImpl(Reader reader) {
 122         this.lexer = new SCLPostLexer(reader);
 123     }
 124
 125     public void setCompilationContext(CompilationContext context) {
 126         this.context = context;
 127         lexer.setCompilationContext(context);
 128     }
 129
 130     public void setParserOptions(SCLParserOptions options) {
 131         this.options = options;
 132         lexer.setParserOptions(options);
 133     }
 134
 135     public boolean isEmpty() throws Exception {
 136         return lexer.peekToken().id == SCLTerminals.EOF;
 137     }
 138
 139     @Override
 140     protected Token nextToken() {
 141         try {
 142             Token token = lexer.nextToken();
 143             /*System.out.println("TOKEN " + token.text + " (" + TERMINAL_NAMES[token.id] + ")" +
 144                     " ["
 145                     + Locations.beginOf(token.location) + ".."
 146                     + Locations.endOf(token.location) + "]");*/
 147             return token;
 148         } catch(Exception e) {
 149             if(e instanceof RuntimeException)
 150                 throw (RuntimeException)e;
 151             else
 152                 throw new RuntimeException(e);
 153         }
 154     }
 155
 156     @Override
 157     protected Object reduceDeclarations() {
 158         ArrayList<DeclarationAst> declarations = new ArrayList<DeclarationAst>(length()/2);
 159         for(int i=1;i<length();i+=2)
 160             declarations.add((DeclarationAst)get(i));
 161         return declarations;
 162     }
 163
 164     @Override
 165     protected Object reduceModule() {
 166         ArrayList<DeclarationAst> declarations = new ArrayList<DeclarationAst>(length()/2+1);
 167         for(int i=0;i<length();i+=2) {
 168             DeclarationAst declaration = (DeclarationAst)get(i);
 169             if(declaration == null)
 170                 continue;
 171             declarations.add(declaration);
 172         }
 173         return declarations;
 174     }
 175
 176     @Override
 177     protected Object reduceModuleHeader() {
 178         FieldAssignment[] fields = new FieldAssignment[length()/2-1];
 179         for(int i=0;i<fields.length;++i)
 180             fields[i] = (FieldAssignment)get(2+i*2);
 181         context.header = ModuleHeader.process(context.errorLog, fields);
 182         return null;
 183     }
 184
 185     @Override
 186     protected Object reduceLocalTypeAnnotation() {
 187         if(length() == 1)
 188             return get(0);
 189         return new ETypeAnnotation((Expression)get(0), (TypeAst)get(2));
 190     }
 191
 192     @Override
 193     protected Object reduceTypeAnnotation() {
 194         EVar[] names = new EVar[length()/2];
 195         for(int i=0;i<names.length;++i)
 196             names[i] = (EVar)get(i*2);
 197         return new DValueTypeAst(
 198                 names,
 199                 (TypeAst)get(length()-1)
 200                 );
 201     }
 202
 203     @Override
 204     protected Object reduceValueDefinition() {
 205         Expression rhs = (Expression)get(1);
 206         return new DValueAst((Expression)get(0), rhs);
 207     }
 208
 209     @Override
 210     protected Object reduceDataDefinition() {
 211         int i=2;
 212         ArrayList<String> parameters = new ArrayList<String>();
 213         while(i < length()) {
 214             Token token = (Token)get(i++);
 215             if(token.id != SCLTerminals.ID)
 216                 break;
 217             parameters.add(token.text);
 218         }
 219         ArrayList<ConstructorAst> constructors = new ArrayList<ConstructorAst>();
 220         for(;i < length();i+=2)
 221             constructors.add((ConstructorAst)get(i));
 222         return new DDataAst(
 223                 ((Token)get(1)).text,
 224                 parameters.toArray(new String[parameters.size()]),
 225                 constructors.toArray(new ConstructorAst[constructors.size()]),
 226                 new String[0]
 227                 );
 228     }
 229
 230     @Override
 231     protected Object reduceTypeDefinition() {
 232         int i=2;
 233         ArrayList<String> parameters = new ArrayList<String>();
 234         while(true) {
 235             Token token = (Token)get(i++);
 236             if(token.id != SCLTerminals.ID)
 237                 break;
 238             parameters.add(token.text);
 239         }
 240         return new DTypeAst(
 241                 ((Token)get(1)).text,
 242                 parameters.toArray(new String[parameters.size()]),
 243                 (TypeAst)get(i)
 244                 );
 245     }
 246
 247     @SuppressWarnings("unchecked")
 248     @Override
 249     protected Object reduceClassDefinition() {
 250         int i=1;
 251         ArrayList<TypeAst> context;
 252         if(get(i) instanceof Token)
 253             context = new ArrayList<TypeAst>(0);
 254         else
 255             context = (ArrayList<TypeAst>)get(i++);
 256         String name = ((Token)get(i++)).text;
 257         ArrayList<String> parameters = new ArrayList<String>();
 258         while(i < length()) {
 259             Token token = (Token)get(i);
 260             if(token.id != SCLTerminals.ID)
 261                 break;
 262             parameters.add(token.text);
 263             ++i;
 264         }
 265         ArrayList<DeclarationAst> declarations = null;
 266         FundepAst[] fundeps = FundepAst.EMPTY_ARRAY;
 267         while(i < length()) {
 268             Token token = (Token)get(i++);
 269             if(token.id == SCLTerminals.WHERE) {
 270                 declarations = (ArrayList<DeclarationAst>)get(i++);
 271             }
 272             else if(token.id == SCLTerminals.BAR) {
 273                 fundeps = (FundepAst[])get(i++);
 274             }
 275             else
 276                 throw new InternalCompilerError();
 277         }
 278         return new DClassAst(context, name,
 279                 parameters.toArray(new String[parameters.size()]),
 280                 fundeps,
 281                 declarations);
 282     }
 283
 284     @Override
 285     protected Object reduceFundep() {
 286         String[] from = new String[length()-2];
 287         for(int i=0;i<from.length;++i)
 288             from[i] = ((Token)get(i)).text;
 289         String to = ((Token)get(length()-1)).text;
 290         return new FundepAst(from, to);
 291     }
 292
 293     @Override
 294     protected Object reduceFundeps() {
 295         FundepAst[] fundeps = new FundepAst[(length()+1)/2];
 296         for(int i=0;i<fundeps.length;++i)
 297             fundeps[i] = (FundepAst)get(i*2);
 298         return fundeps;
 299     }
 300
 301     @SuppressWarnings("unchecked")
 302     @Override
 303     protected Object reduceInstanceDefinition() {
 304         int i=1;
 305         ArrayList<TypeAst> context;
 306         if(get(i) instanceof Token)
 307             context = new ArrayList<TypeAst>(0);
 308         else
 309             context = (ArrayList<TypeAst>)get(i++);
 310         Token nameToken = (Token)get(i++);
 311         EVar name = new EVar(nameToken);
 312         ArrayList<TypeAst> parameters = new ArrayList<TypeAst>();
 313         while(i < length()) {
 314             Object symbol = get(i++);
 315             if(symbol instanceof Token)
 316                 break;
 317             parameters.add((TypeAst)symbol);
 318         }
 319         ArrayList<DeclarationAst> declarations = null;
 320         if(i < length())
 321             declarations = (ArrayList<DeclarationAst>)get(i);
 322         return new DInstanceAst(context, name,
 323                 parameters.toArray(new TypeAst[parameters.size()]),
 324                 declarations);
 325     }
 326
 327     @SuppressWarnings("unchecked")
 328     @Override
 329     protected Object reduceDerivingInstanceDefinition() {
 330         int i=2;
 331         ArrayList<TypeAst> context;
 332         if(get(i) instanceof Token)
 333             context = new ArrayList<TypeAst>(0);
 334         else
 335             context = (ArrayList<TypeAst>)get(i++);
 336         Token nameToken = (Token)get(i++);
 337         EVar name = new EVar(nameToken);
 338         ArrayList<TypeAst> parameters = new ArrayList<TypeAst>();
 339         while(i < length()) {
 340             Object symbol = get(i++);
 341             parameters.add((TypeAst)symbol);
 342         }
 343         return new DDerivingInstanceAst(context, name,
 344                 parameters.toArray(new TypeAst[parameters.size()]));
 345     }
 346
 347     @Override
 348     protected Object reduceDocumentationString() {
 349         return new DDocumentationAst(((Token)get(1)).text);
 350     }
 351
 352     @Override
 353     protected Object reduceAnnotation() {
 354         ArrayList<Expression> parameters = new ArrayList<Expression>(length()-1);
 355         for(int i=1;i<length();++i)
 356             parameters.add((Expression)get(i));
 357         return new DAnnotationAst((Token)get(0), parameters);
 358     }
 359
 360     @Override
 361     protected Object reducePrecedenceDefinition() {
 362         EVar[] symbols = new EVar[length()/2];
 363         for(int i=0;i<symbols.length;++i)
 364             symbols[i] = (EVar)get(2*i + 2);
 365         Associativity associativity;
 366         Token token = (Token)get(0);
 367         if(token.text.equals("infixl"))
 368             associativity = Associativity.LEFT;
 369         else if(token.text.equals("infixr"))
 370             associativity = Associativity.RIGHT;
 371         else
 372             associativity = Associativity.NONASSOC;
 373         return new DFixityAst(
 374                 new Precedence(
 375                         Integer.parseInt(((Token)get(1)).text),
 376                         associativity),
 377                         symbols);
 378     }
 379
 380     @Override
 381     protected Object reduceImport() {
 382         // (AS ID)? importSpec?
 383         int pos = 0;
 384         String importKeyword = ((Token)get(pos++)).text; // (IMPORT | INCLUDE)
 385         ++pos; // BEGIN_STRING
 386         String moduleName = ((Token)get(pos++)).text; // END_STRING
 387         String localName = "";
 388         if(pos < length()) {
 389             Object temp = get(pos);
 390             if(temp instanceof Token) {
 391                 Token token = (Token)temp;
 392                 if(token.id == SCLTerminals.AS) {
 393                     ++pos; // AS
 394                     localName = ((Token)get(pos++)).text; // ID
 395                 }
 396             }
 397         }
 398         ImportDeclaration.ImportSpec spec = ImportDeclaration.DEFAULT_SPEC;
 399         if(pos < length())
 400             spec = (ImportDeclaration.ImportSpec)get(pos++);
 401         return new ImportDeclaration(moduleName, localName,
 402                         importKeyword.equals("include"),
 403                         spec);
 404     }
 405
 406     @Override
 407     protected Object reduceJustImport() {
 408         return get(0);
 409     }
 410
 411     @SuppressWarnings("unchecked")
 412     @Override
 413     protected Object reduceImportJava() {
 414         return new DImportJavaAst(((Token)get(2)).text, (ArrayList<DeclarationAst>)get(4));
 415     }
 416
 417     @Override
 418     protected Object reduceEffectDefinition() {
 419         return new DEffectAst(
 420                 ((Token)get(1)).text,
 421                 ((Token)get(3)).text,
 422                 ((Token)get(5)).text);
 423     }
 424
 425     @Override
 426     protected Object reduceVarId() {
 427         return new EVar((Token)get(0));
 428     }
 429
 430     @Override
 431     protected Object reduceEscapedSymbol() {
 432         return new EVar((Token)get(0));
 433     }
 434
 435     @Override
 436     protected Object reduceTupleTypeConstructor() {
 437         return new TVarAst(Types.tupleConstructor(length()-1).name);
 438     }
 439
 440     @Override
 441     protected Object reduceArrow() {
 442         int i=length()-1;
 443         TypeAst result = (TypeAst)get(i);
 444         i-=2;
 445         while(i >= 0) {
 446             if( ((Token)get(i+1)).text.equals("=>") )
 447                 result = new TPredAst((TypeAst)get(i), result);
 448             else
 449                 result = new TFunctionAst((TypeAst)get(i), result);
 450             i-=2;
 451         }
 452         return result;
 453     }
 454
 455     @Override
 456     protected Object reduceBinary() {
 457         if(length() == 1)
 458             return get(0);
 459         int i=0;
 460         EVar negation = null;
 461         if(get(i) instanceof Token) {
 462             Token token = (Token)get(i++);
 463             negation = new EVar(token);
 464         }
 465         EBinary binary = new EBinary((Expression)get(i++), negation);
 466         while(i < length()) {
 467             EVar operator = (EVar)get(i++);
 468             Expression right = (Expression)get(i++);
 469             binary.rights.add(new EBinaryRightSide(operator, right));
 470         }
 471         return binary;
 472     }
 473
 474     @Override
 475     protected Object reduceSimpleRhs() {
 476         if(length() == 2)
 477             return get(1);
 478         else {
 479             EBlock block = (EBlock)get(3);
 480             Expression expression = (Expression)get(1);
 481             block.addStatement(new GuardStatement(expression));
 482             block.location = Locations.location(Locations.beginOf(expression.location), Locations.endOf(block.location));
 483             return block;
 484         }
 485     }
 486
 487     private GuardedExpressionGroup reduceGuardedExpressionGroup(int length) {
 488         GuardedExpression[] expressions = new GuardedExpression[length];
 489         for(int i=0;i<expressions.length;++i) {
 490             expressions[i] = (GuardedExpression)get(i);
 491         }
 492         return new GuardedExpressionGroup(expressions);
 493     }
 494
 495     @Override
 496     protected Object reduceGuardedRhs() {
 497         int length = length();
 498         if(length > 2 && get(length-2) instanceof Token) {
 499             EBlock block = (EBlock)get(length-1);
 500             block.addStatement(new GuardStatement(reduceGuardedExpressionGroup(length-2)));
 501             block.location = Locations.NO_LOCATION;
 502             return block;
 503         }
 504         else
 505             return reduceGuardedExpressionGroup(length);
 506     }
 507
 508     @Override
 509     protected Object reduceStatements() {
 510         EBlock block = new EBlock();
 511         if(length() > 2)
 512             for(int i=1;i<length();i+=2)
 513                 block.addStatement((Statement)get(i));
 514         return block;
 515     }
 516
 517     @Override
 518     protected Object reduceConstructor() {
 519         int idPos;
 520         for(idPos=0;idPos<length();idPos+=2)
 521             if(((Token)get(idPos)).id == SCLTerminals.ID)
 522                 break;
 523         DAnnotationAst[] annotations = idPos == 0 ? DAnnotationAst.EMPTY_ARRAY : new DAnnotationAst[idPos/2];
 524         for(int i=0;i<idPos/2;++i)
 525             annotations[i] = new DAnnotationAst((Token)get(i*2),
 526                     Arrays.asList((Expression)get(i*2+1)));
 527         TypeAst[] parameters = new TypeAst[length()-idPos-1];
 528         for(int i=0;i<parameters.length;++i)
 529             parameters[i] = (TypeAst)get(i+idPos+1);
 530         return new ConstructorAst(annotations, (Token)get(idPos), parameters, null);
 531     }
 532
 533     @Override
 534     protected Object reduceContext() {
 535         ArrayList<TypeAst> result = new ArrayList<TypeAst>(length()/2-1);
 536         for(int i=1;i<length()-2;i+=2)
 537             result.add((TypeAst)get(i));
 538         return result;
 539     }
 540
 541     @Override
 542     protected Object reduceTypeVar() {
 543         return new TVarAst(((Token)get(0)).text);
 544     }
 545
 546     @Override
 547     protected Object reduceTupleType() {
 548         if(length() == 2)
 549             return new TTupleAst(TypeAst.EMPTY_ARRAY);
 550         if(length() == 3) {
 551             Symbol sym = (Symbol)get(1);
 552             sym.location = Locations.NO_LOCATION;
 553             return sym;
 554         }
 555         int dim = length()/2;
 556         TypeAst[] parameters = new TypeAst[dim];
 557         for(int i=0;i<dim;++i)
 558             parameters[i] = (TypeAst)get(i*2+1);
 559         return new TTupleAst(parameters);
 560     }
 561
 562     @Override
 563     protected Object reduceListType() {
 564         return new TListAst((TypeAst)get(1));
 565     }
 566
 567     @Override
 568     protected Object reduceListTypeConstructor() {
 569         return new TVarAst("[]");
 570     }
 571
 572     @Override
 573     protected Object reduceTupleConstructor() {
 574         return new EVar(Types.tupleConstructor(length()-1).name);
 575     }
 576
 577     @Override
 578     protected Object reduceVar() {
 579         return get(0);
 580     }
 581
 582     @Override
 583     protected Object reduceBlank() {
 584         return new EVar(((Token)get(0)).location, "_");
 585     }
 586
 587     @Override
 588     protected Object reduceInteger() {
 589         return new EIntegerLiteral(((Token)get(0)).text);
 590     }
 591
 592     @Override
 593     protected Object reduceFloat() {
 594         return new ERealLiteral(((Token)get(0)).text);
 595     }
 596
 597     @Override
 598     protected Object reduceString() {
 599         return get(0);
 600     }
 601
 602     @Override
 603     protected Object reduceChar() {
 604         String text = ((Token)get(0)).text;
 605         char c = text.charAt(text.length()-2);
 606         if(text.length() == 4) {
 607             switch(c) {
 608             case 'n': c = '\n'; break;
 609             case 't': c = '\t'; break;
 610             case 'b': c = '\b'; break;
 611             case 'f': c = '\f'; break;
 612             case 'r': c = '\r'; break;
 613             }
 614         }
 615         return new ELiteral(new CharacterConstant(c));
 616     }
 617
 618     @Override
 619     protected Object reduceTuple() {
 620         if(length() == 2)
 621             return new EConstant(Builtins.TUPLE_CONSTRUCTORS[0]);
 622         if(length() == 3) {
 623             Symbol sym = (Symbol)get(1);
 624             sym.location = Locations.NO_LOCATION;
 625             return sym;
 626         }
 627         int dim = length()/2;
 628         Expression[] parameters = new Expression[dim];
 629         for(int i=0;i<dim;++i)
 630             parameters[i] = (Expression)get(i*2+1);
 631         EConstant tupleConstructor = new EConstant(Builtins.TUPLE_CONSTRUCTORS[dim]);
 632         tupleConstructor.location = Locations.location(
 633                 Locations.beginOf(((Token)get(0)).location),
 634                 Locations.endOf(((Token)get(length()-1)).location));
 635         return new EApply(tupleConstructor, parameters);
 636     }
 637
 638     public static Expression rightSection(EVar op, Expression e) {
 639         long loc = Locations.combine(op.location, e.location);
 640         Variable var = new Variable("rightSectionTemp");
 641         return new ESimpleLambda(loc, var,
 642                 new EApply(loc, op, new EVariable(loc, var), e));
 643     }
 644
 645     @Override
 646     protected Object reduceRightSection() {
 647         Variable var = new Variable("rightSectionTemp");
 648         long loc = Locations.combine(((Token)get(0)).location, ((Token)get(length()-1)).location);
 649         EVar symbol = (EVar)get(1);
 650         return new ESimpleLambda(var,
 651                 new EApply(loc, symbol,
 652                         new EVariable(loc, var), (Expression)get(2)));
 653     }
 654
 655     @Override
 656     protected Object reduceLeftSection() {
 657         return new EApply((EVar)get(2), (Expression)get(1));
 658     }
 659
 660     @Override
 661     protected Object reduceListLiteral() {
 662         if(length() == 2)
 663             return new EListLiteral(Expression.EMPTY_ARRAY);
 664         int dim = length()/2;
 665         Expression[] components = new Expression[dim];
 666         for(int i=0;i<dim;++i)
 667             components[i] = (Expression)get(i*2+1);
 668         return new EListLiteral(components);
 669     }
 670
 671     @Override
 672     protected Object reduceRange() {
 673         return new ERange(
 674                 (Expression)get(1),
 675                 (Expression)get(3)
 676                 );
 677     }
 678
 679     @Override
 680     protected Object reduceListComprehension() {
 681         ListQualifier qualifier = (ListQualifier)get(3);
 682         for(int i=5;i<length();i+=2) {
 683             ListQualifier right = (ListQualifier)get(i);
 684             if(right instanceof ListThen) {
 685                 ((ListThen) right).setLeft(qualifier);
 686                 qualifier = right;
 687             }
 688             else
 689                 qualifier = new ListSeq(qualifier, right);
 690         }
 691         return new EListComprehension((Expression)get(1), qualifier);
 692     }
 693
 694     @Override
 695     protected Object reduceAs() {
 696         Token id = (Token)get(0);
 697         return new EAsPattern(new EVar(id.location, id.text), (Expression)get(2));
 698     }
 699
 700     @Override
 701     protected Object reduceGuardedExpEq() {
 702         Expression[] guards = new Expression[length()/2-1];
 703         for(int i=0;i<guards.length;++i)
 704             guards[i] = (Expression)get(i*2+1);
 705         return new GuardedExpression(guards, (Expression)get(length()-1));
 706     }
 707
 708     @Override
 709     protected Object reduceLambda() {
 710         Expression[] patterns = new Expression[length()-3];
 711         for(int i=0;i<patterns.length;++i)
 712             patterns[i] = (Expression)get(i+1);
 713         Case case_ = new Case(patterns, (Expression)get(length()-1));
 714         case_.setLhs(Locations.combine(patterns[0].location, patterns[patterns.length-1].location));
 715         return new ELambda(case_);
 716     }
 717
 718     @Override
 719     protected Object reduceLambdaMatch() {
 720         Case[] cases = new Case[length()/2-1];
 721         for(int i=0;i<cases.length;++i)
 722             cases[i] = (Case)get(i*2+2);
 723         return new ELambda(cases);
 724     }
 725
 726     @Override
 727     protected Object reduceLet() {
 728         EBlock block = (EBlock)get(1);
 729         Expression expression = (Expression)get(3);
 730         block.addStatement(new GuardStatement(expression));
 731         Token letToken = (Token)get(0);
 732         block.location = Locations.location(
 733                 Locations.beginOf(letToken.location),
 734                 Locations.endOf(expression.location));
 735         return block;
 736     }
 737
 738     @Override
 739     protected Object reduceIf() {
 740         return new EIf(
 741                 (Expression)get(1),
 742                 (Expression)get(3),
 743                 length() == 6 ? (Expression)get(5) : null);
 744     }
 745
 746     @Override
 747     protected Object reduceMatch() {
 748         Case[] cases = new Case[length()/2-2];
 749         for(int i=0;i<cases.length;++i)
 750             cases[i] = (Case)get(i*2+4);
 751         return new EMatch((Expression)get(1), cases);
 752     }
 753
 754     @Override
 755     protected Object reduceDo() {
 756         EBlock block = (EBlock)get(1);
 757         Token doToken = (Token)get(0);
 758         block.setMonadic( doToken.text.equals("mdo") );
 759         block.location = Locations.location(Locations.beginOf(doToken.location), Locations.endOf(block.location));
 760         return block;
 761     }
 762
 763     @Override
 764     protected Object reduceSelect() {
 765         return new ESelect(((Token)get(0)).id, (Expression)get(1), new QConjunction((Query[])get(3)));
 766     }
 767
 768     @Override
 769     protected Object reduceEnforce() {
 770         return new EEnforce(new QConjunction((Query[])get(1)));
 771     }
 772
 773     @Override
 774     protected Object reduceApply() {
 775         if(length() == 1)
 776             return get(0);
 777         Expression[] parameters = new Expression[length()-1];
 778         for(int i=0;i<parameters.length;++i)
 779             parameters[i] = (Expression)get(i+1);
 780         return new EApply((Expression)get(0), parameters);
 781     }
 782
 783     @Override
 784     protected Object reduceSymbol() {
 785         return new EVar(((Token)get(0)).text);
 786     }
 787
 788     @Override
 789     protected Object reduceEscapedId() {
 790         return new EVar(((Token)get(0)).text);
 791     }
 792
 793     @Override
 794     protected Object reduceMinus() {
 795         return new EVar(((Token)get(0)).text);
 796     }
 797
 798     @Override
 799     protected Object reduceLess() {
 800         return new EVar(((Token)get(0)).text);
 801     }
 802
 803     @Override
 804     protected Object reduceGreater() {
 805         return new EVar(((Token)get(0)).text);
 806     }
 807
 808     @Override
 809     protected Object reduceDot() {
 810         return new EVar(((Token)get(0)).text);
 811     }
 812
 813     @Override
 814     protected Object reduceCase() {
 815         return new Case((Expression)get(0), (Expression)get(1));
 816     }
 817
 818     @Override
 819     protected Object reduceGuardQualifier() {
 820         return new ListGuard((Expression)get(0));
 821     }
 822
 823     @Override
 824     protected Object reduceLetQualifier() {
 825         return new ListAssignment((Expression)get(0), (Expression)get(2));
 826     }
 827
 828     @Override
 829     protected Object reduceBindQualifier() {
 830         return new ListGenerator((Expression)get(0), (Expression)get(2));
 831     }
 832
 833     @Override
 834     protected Object reduceThenQualifier() {
 835         return new ListThen((Expression)get(1), length()==4 ? (Expression)get(3) : null);
 836     }
 837
 838     @Override
 839     protected Object reduceGuardStatement() {
 840         return new GuardStatement((Expression)get(0));
 841     }
 842
 843     @Override
 844     protected Object reduceLetStatement() {
 845         return new LetStatement((Expression)get(0), (Expression)get(1));
 846     }
 847
 848     @Override
 849     protected Object reduceBindStatement() {
 850         return new BindStatement((Expression)get(0), (Expression)get(2));
 851     }
 852
 853     @Override
 854     protected Object reduceSimpleCaseRhs() {
 855         return get(1);
 856     }
 857
 858     @Override
 859     protected Object reduceGuardedCaseRhs() {
 860         GuardedExpression[] expressions = new GuardedExpression[length()];
 861         for(int i=0;i<expressions.length;++i)
 862             expressions[i] = (GuardedExpression)get(i);
 863         return new GuardedExpressionGroup(expressions);
 864     }
 865
 866     @Override
 867     protected Object reduceGuardedExpArrow() {
 868         Expression[] guards = new Expression[length()/2-1];
 869         for(int i=0;i<guards.length;++i)
 870             guards[i] = (Expression)get(i*2+1);
 871         return new GuardedExpression(guards, (Expression)get(length()-1));
 872     }
 873
 874     @Override
 875     protected Object reduceEffect() {
 876         ArrayList<TypeAst> effects = new ArrayList<TypeAst>(length()/2-1);
 877         for(int i=1;i<length()-1;i+=2) {
 878             Token token = (Token)get(i);
 879             TVarAst ast = new TVarAst(token.text);
 880             ast.location = token.location;
 881             effects.add(ast);
 882         }
 883         return new TEffectAst(effects, (TypeAst)get(length()-1));
 884     }
 885
 886     @Override
 887     protected Object reduceJustEtype() {
 888         return get(0);
 889     }
 890
 891     @Override
 892     protected Object reduceForAll() {
 893         String[] vars = new String[length()-3];
 894         for(int i=0;i<vars.length;++i)
 895             vars[i] = ((Token)get(i+1)).text;
 896         return new TForAllAst(vars, (TypeAst)get(length()-1));
 897     }
 898
 899     @Override
 900     protected Object reduceApplyType() {
 901         TypeAst[] parameters = new TypeAst[length()-1];
 902         for(int i=0;i<parameters.length;++i)
 903             parameters[i] = (TypeAst)get(i+1);
 904         return new TApplyAst((TypeAst)get(0), parameters);
 905     }
 906
 907     @SuppressWarnings("unchecked")
 908     @Override
 909     protected void postReduce(Object reduced) {
 910         if(!(reduced instanceof Symbol))
 911             return;
 912         Symbol sym = (Symbol)reduced;
 913         if(sym.location != Locations.NO_LOCATION || length() == 0)
 914             return;
 915         Object first = get(0);
 916         if(!(first instanceof Symbol)) {
 917             if(first instanceof List) {
 918                 List<Object> ll = (List<Object>)first;
 919                 first = ll.get(0);
 920             }
 921             else {
 922                 Object[] ll = (Object[])first;
 923                 if(ll.length > 0)
 924                     first = ll[0];
 925                 else
 926                     first = get(1);
 927             }
 928         }
 929         Object last = get(length()-1);
 930         if(!(last instanceof Symbol)) {
 931             if(last instanceof List) {
 932                 List<Object> ll = (List<Object>)last;
 933                 last = ll.get(ll.size()-1);
 934             }
 935             else {
 936                 Object[] ll = (Object[])last;
 937                 if(ll.length > 0)
 938                     last = ll[ll.length-1];
 939                 else
 940                     last = get(length()-2);
 941             }
 942         }
 943         sym.location = (((Symbol)first).location & 0xffffffff00000000L)
 944                 | (((Symbol)last).location & 0xffffffffL);
 945         /*for(int i=0;i<length();++i) {
 946             Object obj = get(i);
 947             System.out.print(obj.getClass().getSimpleName());
 948             if(obj instanceof Token) {
 949                 Token t = (Token)obj;
 950                 System.out.print("(" + t.text + ")");
 951             }
 952             if(obj instanceof Symbol) {
 953                 Symbol s = (Symbol)obj;
 954                 System.out.print("["+ Locations.beginOf(s.location) + "-" + Locations.endOf(s.location) + "]");
 955             }
 956             System.out.print(" ");
 957         }
 958         System.out.println("-> " + reduced.getClass().getSimpleName() + " " +
 959                 Locations.beginOf(sym.location) + "-" + Locations.endOf(sym.location));*/
 960     }
 961
 962     @Override
 963     protected RuntimeException syntaxError(Token token, String description) {
 964         throw new SCLSyntaxErrorException(token.location, description);
 965     }
 966
 967     @Override
 968     protected Object reduceIdAccessor() {
 969         return new IdAccessor('.', ((Token)get(0)).text);
 970     }
 971
 972     @Override
 973     protected Object reduceStringAccessor() {
 974         return new StringAccessor('.', ((Token)get(1)).text);
 975     }
 976
 977     @Override
 978     protected Object reduceExpAccessor() {
 979         return new ExpressionAccessor('.', (Expression)get(1));
 980     }
 981
 982     @Override
 983     protected Object reduceFieldAccess() {
 984         if(length() == 1)
 985             return get(0);
 986         Expression result = (Expression)get(0);
 987         for(int i=2;i<length();i+=2) {
 988             FieldAccessor accessor = (FieldAccessor)get(i);
 989             accessor.accessSeparator = ((Token)get(i-1)).text.charAt(0);
 990             result = new EFieldAccess(result, accessor);
 991         }
 992         return result;
 993     }
 994
 995     @Override
 996     protected Object reduceQueryBlock() {
 997         if(length() == 2)
 998             return Query.EMPTY_ARRAY;
 999         Query[] queries = new Query[length()/2];
1000         for(int i=0;i<queries.length;++i)
1001             queries[i] = (Query)get(2*i+1);
1002         return queries;
1003     }
1004
1005     @Override
1006     protected Object reduceGuardQuery() {
1007         return new QPreGuard((Expression)get(0));
1008     }
1009
1010     @Override
1011     protected Object reduceEqualsQuery() {
1012         return new QPreEquals((Expression)get(0), (Expression)get(2));
1013     }
1014
1015     @Override
1016     protected Object reduceBindQuery() {
1017         return new QPreBinds((Expression)get(0), (Expression)get(2));
1018     }
1019
1020     @Override
1021     protected Object reduceCompositeQuery() {
1022         Query[] queries = (Query[])get(1);
1023         switch(((Token)get(0)).text.charAt(1)) {
1024         case '&': return new QConjunction(queries);
1025         case '|': return new QDisjunction(queries);
1026         case '!': return new QNegation(new QConjunction(queries));
1027         case '?': return new QAlternative(queries);
1028         default: throw new InternalCompilerError();
1029         }
1030     }
1031
1032     @Override
1033     protected Object reduceRuleStatement() {
1034         return new RuleStatement((Expression)get(0), new QConjunction((Query[])get(2)));
1035     }
1036
1037     @Override
1038     protected Object reduceHashedId() {
1039         return new EVar("#" + ((Token)get(1)).text);
1040     }
1041
1042     @Override
1043     protected Object reduceStringLiteral() {
1044         int expCount = length()/3;
1045         if(expCount == 0)
1046             return new ELiteral(new StringConstant(((Token)get(1)).text));
1047         else {
1048             String[] strings = new String[expCount+1];
1049             Expression[] expressions = new Expression[expCount];
1050             for(int i=0;i<expCount;++i) {
1051                 strings[i] = ((Token)get(i*3+1)).text;
1052                 expressions[i] = (Expression)get(i*3+2);
1053             }
1054             strings[expCount] = ((Token)get(expCount*3+1)).text;
1055             return new EStringLiteral(strings, expressions);
1056         }
1057     }
1058
1059     @Override
1060     protected Object reduceOneCommand() {
1061         return null;
1062     }
1063
1064     @Override
1065     protected Object reduceManyCommands() {
1066         return null;
1067     }
1068
1069     @Override
1070     protected Object reduceStatementCommand() {
1071         // to be extended in subclasses
1072         return null;
1073     }
1074
1075     @Override
1076     protected Object reduceImportCommand() {
1077         // to be extended in subclasses
1078         return null;
1079     }
1080
1081     @Override
1082     protected Object reduceImportValueItem() {
1083         return new EVar(((Token)get(0)).text);
1084     }
1085
1086     @Override
1087     protected Object reduceImportHiding() {
1088         EVar[] values = new EVar[(length()-2)/2];
1089         for(int i=0;i<values.length;++i)
1090             values[i] = (EVar)get(i*2+2);
1091         return new ImportDeclaration.ImportSpec(true, values);
1092     }
1093
1094     @Override
1095     protected Object reduceImportShowing() {
1096         EVar[] values = new EVar[(length()-1)/2];
1097         for(int i=0;i<values.length;++i)
1098             values[i] = (EVar)get(i*2+1);
1099         return new ImportDeclaration.ImportSpec(false, values);
1100     }
1101
1102     @Override
1103     protected Object reduceRuleDeclarations() {
1104         ArrayList<Object> declarations = new ArrayList<Object>(length()/2);
1105         for(int i=1;i<length();i+=2)
1106             declarations.add((Object)get(i));
1107         return declarations;
1108     }
1109
1110     private static final String[] EMPTY_STRING_ARRAY = new String[0];
1111
1112     @SuppressWarnings("unchecked")
1113     @Override
1114     protected Object reduceRuleDefinition() {
1115         String[] extendsNames = EMPTY_STRING_ARRAY;
1116         if(length() >= 6) {
1117             int extendsCount = (length() - 4) / 2;
1118             extendsNames = new String[extendsCount];
1119             for(int i=0;i<extendsCount;++i)
1120                 extendsNames[i] = ((Token)get(3+i*2)).text;
1121         }
1122
1123         DRuleAst rule = new DRuleAst(
1124                 ((Token)get(0)).id == SCLTerminals.ABSTRACT_RULE,
1125                 ((Token)get(1)).text,
1126                 extendsNames);
1127
1128         ArrayList<Object> ruleDeclarations = (ArrayList<Object>)get(length()-1);
1129         ArrayList<Query> section = null;
1130         for(Object decl : ruleDeclarations) {
1131             if(decl instanceof DAnnotationAst) {
1132                 DAnnotationAst annotation = (DAnnotationAst)decl;
1133                 section = rule.getSection(annotation.id.text.substring(1));
1134             }
1135             else if(decl instanceof Query) {
1136                 if(section == null)
1137                     section = rule.getSection("when");
1138                 section.add((Query)decl);
1139             }
1140             else
1141                 throw new InternalCompilerError();
1142         }
1143         return rule;
1144     }
1145
1146     @Override
1147     protected Object reduceQueryRuleDeclaration() {
1148         return get(0);
1149     }
1150
1151     @Override
1152     protected Object reduceMappingRelationDefinition() {
1153         TypeAst[] types = new TypeAst[length()-2];
1154         for(int i=0;i<types.length;++i)
1155             types[i] = (TypeAst)get(i+2);
1156         return new DMappingRelationAst(
1157                 ((Token)get(1)).text,
1158                 types);
1159     }
1160
1161     @Override
1162     protected Object reduceTransformation() {
1163         return new ETransformation(
1164                 ((Token)get(1)).text,
1165                 new QConjunction((Query[])get(3))
1166                 );
1167     }
1168
1169     @SuppressWarnings("unchecked")
1170     @Override
1171     protected Object reduceRelationDefinition() {
1172         return new DRelationAst((Expression)get(0),
1173                 ((ArrayList<Object>)get(2)).toArray());
1174     }
1175
1176     @Override
1177     protected Object reduceRecord() {
1178         FieldAssignment[] fields = new FieldAssignment[length()/2-1];
1179         for(int i=0;i<fields.length;++i)
1180             fields[i] = (FieldAssignment)get(2+i*2);
1181         return new ERecord(new EVar((Token)get(0)), fields);
1182     }
1183
1184     @Override
1185     protected Object reduceField() {
1186         return new FieldAssignment(((Token)get(0)).text, (Expression)get(2));
1187     }
1188
1189     @Override
1190     protected Object reduceFieldShorthand() {
1191         return new FieldAssignment(((Token)get(0)).text, null);
1192     }
1193
1194     @Override
1195     protected Object reduceRecordConstructor() {
1196         int idPos;
1197         for(idPos=0;idPos<length();idPos+=2)
1198             if(((Token)get(idPos)).id == SCLTerminals.ID)
1199                 break;
1200         DAnnotationAst[] annotations = idPos == 0 ? DAnnotationAst.EMPTY_ARRAY : new DAnnotationAst[idPos/2];
1201         for(int i=0;i<idPos/2;++i)
1202             annotations[i] = new DAnnotationAst((Token)get(i*2),
1203                     Arrays.asList((Expression)get(i*2+1)));
1204         TypeAst[] parameters = new TypeAst[(length()-idPos-1)/2];
1205         String[] fieldNames = new String[parameters.length];
1206         for(int i=0;i<parameters.length;++i) {
1207             FieldDescription fieldDesc = (FieldDescription)get(idPos+(i+1)*2);
1208             parameters[i] = fieldDesc.type;
1209             fieldNames[i] = fieldDesc.name;
1210         }
1211         return new ConstructorAst(annotations, (Token)get(idPos), parameters, fieldNames);
1212     }
1213
1214     @Override
1215     protected Object reduceFieldDescription() {
1216         return new FieldDescription(((Token)get(0)).text, (TypeAst)get(2));
1217     }
1218
1219     @Override
1220     protected Object reduceEq() {
1221         return (Expression)get(2);
1222     }
1223
1224     @Override
1225     protected Object reduceEquationBlock() {
1226         if(length() == 0)
1227             return new EEquations(Equation.EMPTY_ARRAY);
1228         Equation[] equations = new Equation[length()/2+1];
1229         for(int i=0;i<equations.length;++i)
1230             equations[i] = (Equation)get(2*i);
1231         return new EEquations(equations);
1232     }
1233
1234     @Override
1235     protected Object reduceGuardEquation() {
1236         return new EqGuard((Expression)get(0));
1237     }
1238
1239     @Override
1240     protected Object reduceBasicEquation() {
1241         return new EqBasic((Expression)get(0), (Expression)get(2));
1242     }
1243
1244     @Override
1245     protected Object reduceViewPattern() {
1246         return new EViewPattern((Expression)get(1), (Expression)get(3));
1247     }
1248
1249     @Override
1250     protected Object reduceCHRStatement() {
1251         return new CHRStatement((ListQualifier[])get(0), (ListQualifier[])get(2));
1252     }
1253
1254     @Override
1255     protected Object reduceConstraintStatement() {
1256         ConstructorAst constructor = (ConstructorAst)get(1);
1257         return new ConstraintStatement(constructor.name, constructor.parameters, constructor.fieldNames, constructor.annotations);
1258     }
1259
1260     @Override
1261     protected Object reduceCHRQuery() {
1262         ListQualifier[] query = new ListQualifier[(length()+1)/2];
1263         for(int i=0;i<query.length;++i)
1264             query[i] = (ListQualifier)get(i*2);
1265         return query;
1266     }
1267
1268     /*
1269     @Override
1270     protected Object reduceWhen() {
1271         return new EWhen(
1272                 new QConjunction((Query[])get(1)),
1273                 (Expression)get(3));
1274     }*/
1275
1276     @Override
1277     protected Object reduceVerboseCHRQuery() {
1278         ListQualifier[] query = new ListQualifier[(length()-1)/2];
1279         for(int i=0;i<query.length;++i)
1280             query[i] = (ListQualifier)get(i*2+1);
1281         return query;
1282     }
1283
1284     @Override
1285     protected Object reduceVerboseCHRStatement() {
1286         return new CHRStatement((ListQualifier[])get(1), (ListQualifier[])get(3));
1287     }
1288
1289     @Override
1290     protected Object reduceDummy() {
1291         throw new UnsupportedOperationException();
1292     }
1293
1294     @Override
1295     protected Object reduceRulesetDefinition() {
1296         Token name = (Token)get(1);
1297         EBlock block = (EBlock)get(3);
1298         return new DRulesetAst(name.text, block);
1299     }
1300
1301     @Override
1302     protected Object reduceLocalInclude() {
1303         Token name = (Token)get(1);
1304         Expression value = (Expression)get(2);
1305         return new IncludeStatement(name, value);
1306     }
1307
1308     @Override
1309     protected Object reduceConstraintSpec() {
1310         Expression[] expressions = new Expression[length()/2-1];
1311         for(int i=0;i<expressions.length;++i)
1312             expressions[i] = (Expression)get(2*i+1);
1313         return expressions;
1314     }
1315
1316 }