bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/internal/parsing/parser/SCLParserImpl.java

   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.constants.CharacterConstant;
  12 import org.simantics.scl.compiler.constants.StringConstant;
  13 import org.simantics.scl.compiler.elaboration.equation.EqBasic;
  14 import org.simantics.scl.compiler.elaboration.equation.EqGuard;
  15 import org.simantics.scl.compiler.elaboration.equation.Equation;
  16 import org.simantics.scl.compiler.elaboration.expressions.Case;
  17 import org.simantics.scl.compiler.elaboration.expressions.EApply;
  18 import org.simantics.scl.compiler.elaboration.expressions.EAsPattern;
  19 import org.simantics.scl.compiler.elaboration.expressions.EBinary;
  20 import org.simantics.scl.compiler.elaboration.expressions.EBinaryRightSide;
  21 import org.simantics.scl.compiler.elaboration.expressions.EBlock;
  22 import org.simantics.scl.compiler.elaboration.expressions.EConstant;
  23 import org.simantics.scl.compiler.elaboration.expressions.EEnforce;
  24 import org.simantics.scl.compiler.elaboration.expressions.EEntityTypeAnnotation;
  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.EWhen;
  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.GuardStatement;
  55 import org.simantics.scl.compiler.elaboration.expressions.block.LetStatement;
  56 import org.simantics.scl.compiler.elaboration.expressions.block.RuleStatement;
  57 import org.simantics.scl.compiler.elaboration.expressions.block.Statement;
  58 import org.simantics.scl.compiler.elaboration.expressions.list.ListAssignment;
  59 import org.simantics.scl.compiler.elaboration.expressions.list.ListGenerator;
  60 import org.simantics.scl.compiler.elaboration.expressions.list.ListGuard;
  61 import org.simantics.scl.compiler.elaboration.expressions.list.ListQualifier;
  62 import org.simantics.scl.compiler.elaboration.expressions.list.ListSeq;
  63 import org.simantics.scl.compiler.elaboration.expressions.list.ListThen;
  64 import org.simantics.scl.compiler.elaboration.expressions.records.FieldAssignment;
  65 import org.simantics.scl.compiler.elaboration.java.Builtins;
  66 import org.simantics.scl.compiler.elaboration.query.QAlternative;
  67 import org.simantics.scl.compiler.elaboration.query.QConjunction;
  68 import org.simantics.scl.compiler.elaboration.query.QDisjunction;
  69 import org.simantics.scl.compiler.elaboration.query.QNegation;
  70 import org.simantics.scl.compiler.elaboration.query.Query;
  71 import org.simantics.scl.compiler.elaboration.query.pre.QPreBinds;
  72 import org.simantics.scl.compiler.elaboration.query.pre.QPreEquals;
  73 import org.simantics.scl.compiler.elaboration.query.pre.QPreGuard;
  74 import org.simantics.scl.compiler.errors.Locations;
  75 import org.simantics.scl.compiler.internal.parsing.Symbol;
  76 import org.simantics.scl.compiler.internal.parsing.Token;
  77 import org.simantics.scl.compiler.internal.parsing.declarations.ConstructorAst;
  78 import org.simantics.scl.compiler.internal.parsing.declarations.DAnnotationAst;
  79 import org.simantics.scl.compiler.internal.parsing.declarations.DClassAst;
  80 import org.simantics.scl.compiler.internal.parsing.declarations.DDataAst;
  81 import org.simantics.scl.compiler.internal.parsing.declarations.DDerivingInstanceAst;
  82 import org.simantics.scl.compiler.internal.parsing.declarations.DDocumentationAst;
  83 import org.simantics.scl.compiler.internal.parsing.declarations.DEffectAst;
  84 import org.simantics.scl.compiler.internal.parsing.declarations.DFixityAst;
  85 import org.simantics.scl.compiler.internal.parsing.declarations.DImportJavaAst;
  86 import org.simantics.scl.compiler.internal.parsing.declarations.DInstanceAst;
  87 import org.simantics.scl.compiler.internal.parsing.declarations.DMappingRelationAst;
  88 import org.simantics.scl.compiler.internal.parsing.declarations.DRelationAst;
  89 import org.simantics.scl.compiler.internal.parsing.declarations.DRuleAst;
  90 import org.simantics.scl.compiler.internal.parsing.declarations.DTypeAst;
  91 import org.simantics.scl.compiler.internal.parsing.declarations.DValueAst;
  92 import org.simantics.scl.compiler.internal.parsing.declarations.DValueTypeAst;
  93 import org.simantics.scl.compiler.internal.parsing.declarations.DeclarationAst;
  94 import org.simantics.scl.compiler.internal.parsing.declarations.FieldDescription;
  95 import org.simantics.scl.compiler.internal.parsing.declarations.FundepAst;
  96 import org.simantics.scl.compiler.internal.parsing.exceptions.SCLSyntaxErrorException;
  97 import org.simantics.scl.compiler.internal.parsing.types.TApplyAst;
  98 import org.simantics.scl.compiler.internal.parsing.types.TEffectAst;
  99 import org.simantics.scl.compiler.internal.parsing.types.TForAllAst;
 100 import org.simantics.scl.compiler.internal.parsing.types.TFunctionAst;
 101 import org.simantics.scl.compiler.internal.parsing.types.TListAst;
 102 import org.simantics.scl.compiler.internal.parsing.types.TPredAst;
 103 import org.simantics.scl.compiler.internal.parsing.types.TTupleAst;
 104 import org.simantics.scl.compiler.internal.parsing.types.TVarAst;
 105 import org.simantics.scl.compiler.internal.parsing.types.TypeAst;
 106 import org.simantics.scl.compiler.module.ImportDeclaration;
 107 import org.simantics.scl.compiler.types.Types;
 108
 109
 110 public class SCLParserImpl extends SCLParser {
 111
 112     private final SCLPostLexer lexer;
 113     private SCLParserOptions options;
 114
 115     public SCLParserImpl(Reader reader) {
 116         lexer = new SCLPostLexer(reader);
 117     }
 118
 119     public void setParserOptions(SCLParserOptions options) {
 120         this.options = options;
 121         lexer.setParserOptions(options);
 122     }
 123
 124     public boolean isEmpty() throws Exception {
 125         return lexer.peekToken().id == SCLTerminals.EOF;
 126     }
 127
 128     @Override
 129     protected Token nextToken() {
 130         try {
 131             Token token = lexer.nextToken();
 132             /*System.out.println("TOKEN " + token.text + " (" + TERMINAL_NAMES[token.id] + ")" +
 133                     " ["
 134                     + Locations.beginOf(token.location) + ".."
 135                     + Locations.endOf(token.location) + "]");*/
 136             return token;
 137         } catch(Exception e) {
 138             if(e instanceof RuntimeException)
 139                 throw (RuntimeException)e;
 140             else
 141                 throw new RuntimeException(e);
 142         }
 143     }
 144
 145     @Override
 146     protected Object reduceDeclarations() {
 147         ArrayList<DeclarationAst> declarations = new ArrayList<DeclarationAst>(length()/2);
 148         for(int i=1;i<length();i+=2)
 149             declarations.add((DeclarationAst)get(i));
 150         return declarations;
 151     }
 152
 153     @Override
 154     protected Object reduceModule() {
 155         ArrayList<DeclarationAst> declarations = new ArrayList<DeclarationAst>(length()/2+1);
 156         for(int i=0;i<length();i+=2)
 157             declarations.add((DeclarationAst)get(i));
 158         return declarations;
 159     }
 160
 161     @Override
 162     protected Object reduceLocalTypeAnnotation() {
 163         if(length() == 1)
 164             return get(0);
 165         return new ETypeAnnotation((Expression)get(0), (TypeAst)get(2));
 166     }
 167
 168     @Override
 169     protected Object reduceTypeAnnotation() {
 170         EVar[] names = new EVar[length()/2];
 171         for(int i=0;i<names.length;++i)
 172             names[i] = (EVar)get(i*2);
 173         return new DValueTypeAst(
 174                 names,
 175                 (TypeAst)get(length()-1)
 176                 );
 177     }
 178
 179     @Override
 180     protected Object reduceValueDefinition() {
 181         Expression rhs = (Expression)get(1);
 182         return new DValueAst((Expression)get(0), rhs);
 183     }
 184
 185     @Override
 186     protected Object reduceDataDefinition() {
 187         int i=2;
 188         ArrayList<String> parameters = new ArrayList<String>();
 189         while(i < length()) {
 190             Token token = (Token)get(i++);
 191             if(token.id != SCLTerminals.ID)
 192                 break;
 193             parameters.add(token.text);
 194         }
 195         ArrayList<ConstructorAst> constructors = new ArrayList<ConstructorAst>();
 196         for(;i < length();i+=2)
 197             constructors.add((ConstructorAst)get(i));
 198         return new DDataAst(
 199                 ((Token)get(1)).text,
 200                 parameters.toArray(new String[parameters.size()]),
 201                 constructors.toArray(new ConstructorAst[constructors.size()]),
 202                 new String[0]
 203                 );
 204     }
 205
 206     @Override
 207     protected Object reduceTypeDefinition() {
 208         int i=2;
 209         ArrayList<String> parameters = new ArrayList<String>();
 210         while(true) {
 211             Token token = (Token)get(i++);
 212             if(token.id != SCLTerminals.ID)
 213                 break;
 214             parameters.add(token.text);
 215         }
 216         return new DTypeAst(
 217                 ((Token)get(1)).text,
 218                 parameters.toArray(new String[parameters.size()]),
 219                 (TypeAst)get(i)
 220                 );
 221     }
 222
 223     @Override
 224     protected Object reduceClassDefinition() {
 225         int i=1;
 226         ArrayList<TypeAst> context;
 227         if(get(i) instanceof Token)
 228             context = new ArrayList<TypeAst>(0);
 229         else
 230             context = (ArrayList<TypeAst>)get(i++);
 231         String name = ((Token)get(i++)).text;
 232         ArrayList<String> parameters = new ArrayList<String>();
 233         while(i < length()) {
 234             Token token = (Token)get(i);
 235             if(token.id != SCLTerminals.ID)
 236                 break;
 237             parameters.add(token.text);
 238             ++i;
 239         }
 240         ArrayList<DeclarationAst> declarations = null;
 241         FundepAst[] fundeps = FundepAst.EMPTY_ARRAY;
 242         while(i < length()) {
 243             Token token = (Token)get(i++);
 244             if(token.id == SCLTerminals.WHERE) {
 245                 declarations = (ArrayList<DeclarationAst>)get(i++);
 246             }
 247             else if(token.id == SCLTerminals.BAR) {
 248                 fundeps = (FundepAst[])get(i++);
 249             }
 250             else
 251                 throw new InternalCompilerError();
 252         }
 253         return new DClassAst(context, name,
 254                 parameters.toArray(new String[parameters.size()]),
 255                 fundeps,
 256                 declarations);
 257     }
 258
 259     @Override
 260     protected Object reduceFundep() {
 261         String[] from = new String[length()-2];
 262         for(int i=0;i<from.length;++i)
 263             from[i] = ((Token)get(i)).text;
 264         String to = ((Token)get(length()-1)).text;
 265         return new FundepAst(from, to);
 266     }
 267
 268     @Override
 269     protected Object reduceFundeps() {
 270         FundepAst[] fundeps = new FundepAst[(length()+1)/2];
 271         for(int i=0;i<fundeps.length;++i)
 272             fundeps[i] = (FundepAst)get(i*2);
 273         return fundeps;
 274     }
 275
 276     @Override
 277     protected Object reduceInstanceDefinition() {
 278         int i=1;
 279         ArrayList<TypeAst> context;
 280         if(get(i) instanceof Token)
 281             context = new ArrayList<TypeAst>(0);
 282         else
 283             context = (ArrayList<TypeAst>)get(i++);
 284         Token nameToken = (Token)get(i++);
 285         EVar name = new EVar(nameToken.location, nameToken.text);
 286         ArrayList<TypeAst> parameters = new ArrayList<TypeAst>();
 287         while(i < length()) {
 288             Object symbol = get(i++);
 289             if(symbol instanceof Token)
 290                 break;
 291             parameters.add((TypeAst)symbol);
 292         }
 293         ArrayList<DeclarationAst> declarations = null;
 294         if(i < length())
 295             declarations = (ArrayList<DeclarationAst>)get(i);
 296         return new DInstanceAst(context, name,
 297                 parameters.toArray(new TypeAst[parameters.size()]),
 298                 declarations);
 299     }
 300
 301     @Override
 302     protected Object reduceDerivingInstanceDefinition() {
 303         int i=2;
 304         ArrayList<TypeAst> context;
 305         if(get(i) instanceof Token)
 306             context = new ArrayList<TypeAst>(0);
 307         else
 308             context = (ArrayList<TypeAst>)get(i++);
 309         Token nameToken = (Token)get(i++);
 310         EVar name = new EVar(nameToken.location, nameToken.text);
 311         ArrayList<TypeAst> parameters = new ArrayList<TypeAst>();
 312         while(i < length()) {
 313             Object symbol = get(i++);
 314             parameters.add((TypeAst)symbol);
 315         }
 316         return new DDerivingInstanceAst(context, name,
 317                 parameters.toArray(new TypeAst[parameters.size()]));
 318     }
 319
 320     @Override
 321     protected Object reduceDocumentationString() {
 322         return new DDocumentationAst(((Token)get(1)).text);
 323     }
 324
 325     @Override
 326     protected Object reduceAnnotation() {
 327         ArrayList<Expression> parameters = new ArrayList<Expression>(length()-1);
 328         for(int i=1;i<length();++i)
 329             parameters.add((Expression)get(i));
 330         return new DAnnotationAst((Token)get(0), parameters);
 331     }
 332
 333     @Override
 334     protected Object reducePrecedenceDefinition() {
 335         EVar[] symbols = new EVar[length()/2];
 336         for(int i=0;i<symbols.length;++i)
 337             symbols[i] = (EVar)get(2*i + 2);
 338         Associativity associativity;
 339         Token token = (Token)get(0);
 340         if(token.text.equals("infixl"))
 341             associativity = Associativity.LEFT;
 342         else if(token.text.equals("infixr"))
 343             associativity = Associativity.RIGHT;
 344         else
 345             associativity = Associativity.NONASSOC;
 346         return new DFixityAst(
 347                 new Precedence(
 348                         Integer.parseInt(((Token)get(1)).text),
 349                         associativity),
 350                         symbols);
 351     }
 352
 353     @Override
 354     protected Object reduceImport() {
 355         // (AS ID)? importSpec?
 356         int pos = 0;
 357         String importKeyword = ((Token)get(pos++)).text; // (IMPORT | INCLUDE)
 358         ++pos; // BEGIN_STRING
 359         String moduleName = ((Token)get(pos++)).text; // END_STRING
 360         String localName = "";
 361         if(pos < length()) {
 362             Object temp = get(pos);
 363             if(temp instanceof Token) {
 364                 Token token = (Token)temp;
 365                 if(token.id == SCLTerminals.AS) {
 366                     ++pos; // AS
 367                     localName = ((Token)get(pos++)).text; // ID
 368                 }
 369             }
 370         }
 371         ImportDeclaration.ImportSpec spec = ImportDeclaration.DEFAULT_SPEC;
 372         if(pos < length())
 373             spec = (ImportDeclaration.ImportSpec)get(pos++);
 374         return new ImportDeclaration(moduleName, localName,
 375                         importKeyword.equals("include"),
 376                         spec);
 377     }
 378
 379     @Override
 380     protected Object reduceJustImport() {
 381         return get(0);
 382     }
 383
 384     @Override
 385     protected Object reduceImportJava() {
 386         return new DImportJavaAst(((Token)get(2)).text, (ArrayList<DeclarationAst>)get(4));
 387     }
 388
 389     @Override
 390     protected Object reduceEffectDefinition() {
 391         return new DEffectAst(
 392                 ((Token)get(1)).text,
 393                 ((Token)get(3)).text,
 394                 ((Token)get(5)).text);
 395     }
 396
 397     @Override
 398     protected Object reduceVarId() {
 399         return new EVar(((Token)get(0)).text);
 400     }
 401
 402     @Override
 403     protected Object reduceEscapedSymbol() {
 404         return new EVar(((Token)get(0)).text);
 405     }
 406
 407     @Override
 408     protected Object reduceTupleTypeConstructor() {
 409         return new TVarAst(Types.tupleConstructor(length()-1).name);
 410     }
 411
 412     @Override
 413     protected Object reduceArrow() {
 414         int i=length()-1;
 415         TypeAst result = (TypeAst)get(i);
 416         i-=2;
 417         while(i >= 0) {
 418             if( ((Token)get(i+1)).text.equals("=>") )
 419                 result = new TPredAst((TypeAst)get(i), result);
 420             else
 421                 result = new TFunctionAst((TypeAst)get(i), result);
 422             i-=2;
 423         }
 424         return result;
 425     }
 426
 427     @Override
 428     protected Object reduceBinary() {
 429         if(length() == 1)
 430             return get(0);
 431         int i=0;
 432         EVar negation = null;
 433         if(get(i) instanceof Token) {
 434             Token token = (Token)get(i++);
 435             negation = new EVar(token.location, token.text);
 436         }
 437         EBinary binary = new EBinary((Expression)get(i++), negation);
 438         while(i < length()) {
 439             EVar operator = (EVar)get(i++);
 440             Expression right = (Expression)get(i++);
 441             binary.rights.add(new EBinaryRightSide(operator, right));
 442         }
 443         return binary;
 444     }
 445
 446     @Override
 447     protected Object reduceSimpleRhs() {
 448         if(length() == 2)
 449             return get(1);
 450         else {
 451             EBlock block = (EBlock)get(3);
 452             Expression expression = (Expression)get(1);
 453             block.addStatement(new GuardStatement(expression));
 454             block.location = Locations.location(Locations.beginOf(expression.location), Locations.endOf(block.location));
 455             return block;
 456         }
 457     }
 458
 459     private GuardedExpressionGroup reduceGuardedExpressionGroup(int length) {
 460         GuardedExpression[] expressions = new GuardedExpression[length];
 461         for(int i=0;i<expressions.length;++i) {
 462             expressions[i] = (GuardedExpression)get(i);
 463         }
 464         return new GuardedExpressionGroup(expressions);
 465     }
 466
 467     @Override
 468     protected Object reduceGuardedRhs() {
 469         int length = length();
 470         if(length > 2 && get(length-2) instanceof Token) {
 471             EBlock block = (EBlock)get(length-1);
 472             block.addStatement(new GuardStatement(reduceGuardedExpressionGroup(length-2)));
 473             block.location = Locations.NO_LOCATION;
 474             return block;
 475         }
 476         else
 477             return reduceGuardedExpressionGroup(length);
 478     }
 479
 480     @Override
 481     protected Object reduceStatements() {
 482         EBlock block = new EBlock();
 483         for(int i=1;i<length();i+=2)
 484             block.addStatement((Statement)get(i));
 485         return block;
 486     }
 487
 488     @Override
 489     protected Object reduceConstructor() {
 490         int idPos;
 491         for(idPos=0;idPos<length();idPos+=2)
 492             if(((Token)get(idPos)).id == SCLTerminals.ID)
 493                 break;
 494         DAnnotationAst[] annotations = idPos == 0 ? DAnnotationAst.EMPTY_ARRAY : new DAnnotationAst[idPos/2];
 495         for(int i=0;i<idPos/2;++i)
 496             annotations[i] = new DAnnotationAst((Token)get(i*2),
 497                     Arrays.asList((Expression)get(i*2+1)));
 498         TypeAst[] parameters = new TypeAst[length()-idPos-1];
 499         for(int i=0;i<parameters.length;++i)
 500             parameters[i] = (TypeAst)get(i+idPos+1);
 501         return new ConstructorAst(annotations, ((Token)get(idPos)).text, parameters, null);
 502     }
 503
 504     @Override
 505     protected Object reduceContext() {
 506         ArrayList<TypeAst> result = new ArrayList<TypeAst>(length()/2-1);
 507         for(int i=1;i<length()-2;i+=2)
 508             result.add((TypeAst)get(i));
 509         return result;
 510     }
 511
 512     @Override
 513     protected Object reduceTypeVar() {
 514         return new TVarAst(((Token)get(0)).text);
 515     }
 516
 517     @Override
 518     protected Object reduceTupleType() {
 519         if(length() == 2)
 520             return new TTupleAst(TypeAst.EMPTY_ARRAY);
 521         if(length() == 3) {
 522             Symbol sym = (Symbol)get(1);
 523             sym.location = Locations.NO_LOCATION;
 524             return sym;
 525         }
 526         int dim = length()/2;
 527         TypeAst[] parameters = new TypeAst[dim];
 528         for(int i=0;i<dim;++i)
 529             parameters[i] = (TypeAst)get(i*2+1);
 530         return new TTupleAst(parameters);
 531     }
 532
 533     @Override
 534     protected Object reduceListType() {
 535         return new TListAst((TypeAst)get(1));
 536     }
 537
 538     @Override
 539     protected Object reduceListTypeConstructor() {
 540         return new TVarAst("[]");
 541     }
 542
 543     @Override
 544     protected Object reduceTupleConstructor() {
 545         return new EVar(Types.tupleConstructor(length()-1).name);
 546     }
 547
 548     @Override
 549     protected Object reduceVar() {
 550         return get(0);
 551     }
 552
 553     @Override
 554     protected Object reduceBlank() {
 555         return new EVar("_");
 556     }
 557
 558     @Override
 559     protected Object reduceInteger() {
 560         return new EIntegerLiteral(((Token)get(0)).text);
 561     }
 562
 563     @Override
 564     protected Object reduceFloat() {
 565         return new ERealLiteral(((Token)get(0)).text);
 566     }
 567
 568     @Override
 569     protected Object reduceString() {
 570         return get(0);
 571     }
 572
 573     @Override
 574     protected Object reduceChar() {
 575         String text = ((Token)get(0)).text;
 576         char c = text.charAt(text.length()-2);
 577         if(text.length() == 4) {
 578             switch(c) {
 579             case 'n': c = '\n'; break;
 580             case 't': c = '\t'; break;
 581             case 'b': c = '\b'; break;
 582             case 'f': c = '\f'; break;
 583             case 'r': c = '\r'; break;
 584             }
 585         }
 586         return new ELiteral(new CharacterConstant(c));
 587     }
 588
 589     @Override
 590     protected Object reduceTuple() {
 591         if(length() == 2)
 592             return new EConstant(Builtins.TUPLE_CONSTRUCTORS[0]);
 593         if(length() == 3) {
 594             Symbol sym = (Symbol)get(1);
 595             sym.location = Locations.NO_LOCATION;
 596             return sym;
 597         }
 598         int dim = length()/2;
 599         Expression[] parameters = new Expression[dim];
 600         for(int i=0;i<dim;++i)
 601             parameters[i] = (Expression)get(i*2+1);
 602         EConstant tupleConstructor = new EConstant(Builtins.TUPLE_CONSTRUCTORS[dim]);
 603         tupleConstructor.location = Locations.location(
 604                 Locations.beginOf(((Token)get(0)).location),
 605                 Locations.endOf(((Token)get(length()-1)).location));
 606         return new EApply(tupleConstructor, parameters);
 607     }
 608
 609     public static Expression rightSection(EVar op, Expression e) {
 610         long loc = Locations.combine(op.location, e.location);
 611         Variable var = new Variable("rightSectionTemp");
 612         return new ESimpleLambda(loc, var,
 613                 new EApply(loc, op, new EVariable(loc, var), e));
 614     }
 615
 616     @Override
 617     protected Object reduceRightSection() {
 618         Variable var = new Variable("rightSectionTemp");
 619         long loc = Locations.combine(((Token)get(0)).location, ((Token)get(length()-1)).location);
 620         EVar symbol = (EVar)get(1);
 621         return new ESimpleLambda(var,
 622                 new EApply(loc, symbol,
 623                         new EVariable(loc, var), (Expression)get(2)));
 624     }
 625
 626     @Override
 627     protected Object reduceLeftSection() {
 628         return new EApply((EVar)get(2), (Expression)get(1));
 629     }
 630
 631     @Override
 632     protected Object reduceListLiteral() {
 633         if(length() == 2)
 634             return new EListLiteral(Expression.EMPTY_ARRAY);
 635         int dim = length()/2;
 636         Expression[] components = new Expression[dim];
 637         for(int i=0;i<dim;++i)
 638             components[i] = (Expression)get(i*2+1);
 639         return new EListLiteral(components);
 640     }
 641
 642     @Override
 643     protected Object reduceRange() {
 644         return new ERange(
 645                 (Expression)get(1),
 646                 (Expression)get(3)
 647                 );
 648     }
 649
 650     @Override
 651     protected Object reduceListComprehension() {
 652         ListQualifier qualifier = (ListQualifier)get(3);
 653         for(int i=5;i<length();i+=2) {
 654             ListQualifier right = (ListQualifier)get(i);
 655             if(right instanceof ListThen) {
 656                 ((ListThen) right).setLeft(qualifier);
 657                 qualifier = right;
 658             }
 659             else
 660                 qualifier = new ListSeq(qualifier, right);
 661         }
 662         return new EListComprehension((Expression)get(1), qualifier);
 663     }
 664
 665     @Override
 666     protected Object reduceAs() {
 667         Token id = (Token)get(0);
 668         return new EAsPattern(new EVar(id.location, id.text), (Expression)get(2));
 669     }
 670
 671     @Override
 672     protected Object reduceGuardedExpEq() {
 673         Expression[] guards = new Expression[length()/2-1];
 674         for(int i=0;i<guards.length;++i)
 675             guards[i] = (Expression)get(i*2+1);
 676         return new GuardedExpression(guards, (Expression)get(length()-1));
 677     }
 678
 679     @Override
 680     protected Object reduceLambda() {
 681         Expression[] patterns = new Expression[length()-3];
 682         for(int i=0;i<patterns.length;++i)
 683             patterns[i] = (Expression)get(i+1);
 684         Case case_ = new Case(patterns, (Expression)get(length()-1));
 685         case_.setLhs(Locations.combine(patterns[0].location, patterns[patterns.length-1].location));
 686         return new ELambda(case_);
 687     }
 688
 689     @Override
 690     protected Object reduceLet() {
 691         EBlock block = (EBlock)get(1);
 692         Expression expression = (Expression)get(3);
 693         block.addStatement(new GuardStatement(expression));
 694         Token letToken = (Token)get(0);
 695         block.location = Locations.location(
 696                 Locations.beginOf(letToken.location),
 697                 Locations.endOf(expression.location));
 698         return block;
 699     }
 700
 701     @Override
 702     protected Object reduceIf() {
 703         return new EIf(
 704                 (Expression)get(1),
 705                 (Expression)get(3),
 706                 (Expression)get(5));
 707     }
 708
 709     @Override
 710     protected Object reduceMatch() {
 711         Case[] cases = new Case[length()/2-2];
 712         for(int i=0;i<cases.length;++i)
 713             cases[i] = (Case)get(i*2+4);
 714         return new EMatch((Expression)get(1), cases);
 715     }
 716
 717     @Override
 718     protected Object reduceDo() {
 719         EBlock block = (EBlock)get(1);
 720         Token doToken = (Token)get(0);
 721         block.setMonadic( doToken.text.equals("mdo") );
 722         block.location = Locations.location(Locations.beginOf(doToken.location), Locations.endOf(block.location));
 723         return block;
 724     }
 725
 726     @Override
 727     protected Object reduceSelect() {
 728         return new ESelect(((Token)get(0)).id, (Expression)get(1), new QConjunction((Query[])get(3)));
 729     }
 730
 731     @Override
 732     protected Object reduceWhen() {
 733         return new EWhen(
 734                 new QConjunction((Query[])get(1)),
 735                 (Expression)get(3));
 736     }
 737
 738     @Override
 739     protected Object reduceEnforce() {
 740         return new EEnforce(new QConjunction((Query[])get(1)));
 741     }
 742
 743     @Override
 744     protected Object reduceApply() {
 745         if(length() == 1)
 746             return get(0);
 747         Expression[] parameters = new Expression[length()-1];
 748         for(int i=0;i<parameters.length;++i)
 749             parameters[i] = (Expression)get(i+1);
 750         return new EApply((Expression)get(0), parameters);
 751     }
 752
 753     @Override
 754     protected Object reduceSymbol() {
 755         return new EVar(((Token)get(0)).text);
 756     }
 757
 758     @Override
 759     protected Object reduceEscapedId() {
 760         return new EVar(((Token)get(0)).text);
 761     }
 762
 763     @Override
 764     protected Object reduceMinus() {
 765         return new EVar(((Token)get(0)).text);
 766     }
 767
 768     @Override
 769     protected Object reduceLess() {
 770         return new EVar(((Token)get(0)).text);
 771     }
 772
 773     @Override
 774     protected Object reduceGreater() {
 775         return new EVar(((Token)get(0)).text);
 776     }
 777
 778     @Override
 779     protected Object reduceDot() {
 780         return new EVar(((Token)get(0)).text);
 781     }
 782
 783     @Override
 784     protected Object reduceCase() {
 785         return new Case((Expression)get(0), (Expression)get(1));
 786     }
 787
 788     @Override
 789     protected Object reduceGuardQualifier() {
 790         return new ListGuard((Expression)get(0));
 791     }
 792
 793     @Override
 794     protected Object reduceLetQualifier() {
 795         return new ListAssignment((Expression)get(0), (Expression)get(2));
 796     }
 797
 798     @Override
 799     protected Object reduceBindQualifier() {
 800         return new ListGenerator((Expression)get(0), (Expression)get(2));
 801     }
 802
 803     @Override
 804     protected Object reduceThenQualifier() {
 805         return new ListThen((Expression)get(1), length()==4 ? (Expression)get(3) : null);
 806     }
 807
 808     @Override
 809     protected Object reduceGuardStatement() {
 810         return new GuardStatement((Expression)get(0));
 811     }
 812
 813     @Override
 814     protected Object reduceLetStatement() {
 815         return new LetStatement((Expression)get(0), (Expression)get(1));
 816     }
 817
 818     @Override
 819     protected Object reduceBindStatement() {
 820         return new BindStatement((Expression)get(0), (Expression)get(2));
 821     }
 822
 823     @Override
 824     protected Object reduceSimpleCaseRhs() {
 825         return get(1);
 826     }
 827
 828     @Override
 829     protected Object reduceGuardedCaseRhs() {
 830         GuardedExpression[] expressions = new GuardedExpression[length()];
 831         for(int i=0;i<expressions.length;++i)
 832             expressions[i] = (GuardedExpression)get(i);
 833         return new GuardedExpressionGroup(expressions);
 834     }
 835
 836     @Override
 837     protected Object reduceGuardedExpArrow() {
 838         Expression[] guards = new Expression[length()/2-1];
 839         for(int i=0;i<guards.length;++i)
 840             guards[i] = (Expression)get(i*2+1);
 841         return new GuardedExpression(guards, (Expression)get(length()-1));
 842     }
 843
 844     @Override
 845     protected Object reduceEffect() {
 846         ArrayList<TypeAst> effects = new ArrayList<TypeAst>(length()/2-1);
 847         for(int i=1;i<length()-1;i+=2) {
 848             Token token = (Token)get(i);
 849             TVarAst ast = new TVarAst(token.text);
 850             ast.location = token.location;
 851             effects.add(ast);
 852         }
 853         return new TEffectAst(effects, (TypeAst)get(length()-1));
 854     }
 855
 856     @Override
 857     protected Object reduceJustEtype() {
 858         return get(0);
 859     }
 860
 861     @Override
 862     protected Object reduceForAll() {
 863         String[] vars = new String[length()-3];
 864         for(int i=0;i<vars.length;++i)
 865             vars[i] = ((Token)get(i+1)).text;
 866         return new TForAllAst(vars, (TypeAst)get(length()-1));
 867     }
 868
 869     @Override
 870     protected Object reduceApplyType() {
 871         TypeAst[] parameters = new TypeAst[length()-1];
 872         for(int i=0;i<parameters.length;++i)
 873             parameters[i] = (TypeAst)get(i+1);
 874         return new TApplyAst((TypeAst)get(0), parameters);
 875     }
 876
 877     @Override
 878     protected Object reduceDummy1() {
 879         throw new UnsupportedOperationException();
 880     }
 881
 882     @Override
 883     protected void postReduce(Object reduced) {
 884         if(!(reduced instanceof Symbol))
 885             return;
 886         Symbol sym = (Symbol)reduced;
 887         if(sym.location != Locations.NO_LOCATION || length() == 0)
 888             return;
 889         Object last = get(length()-1);
 890         if(!(last instanceof Symbol)) {
 891             if(last instanceof List) {
 892                 List<Object> ll = (List<Object>)last;
 893                 last = ll.get(ll.size()-1);
 894             }
 895             else {
 896                 Object[] ll = (Object[])last;
 897                 if(ll.length > 0)
 898                     last = ll[ll.length-1];
 899                 else
 900                     last = get(length()-2);
 901             }
 902         }
 903         sym.location = (((Symbol)get(0)).location & 0xffffffff00000000L)
 904                 | (((Symbol)last).location & 0xffffffffL);
 905         /*for(int i=0;i<length();++i) {
 906             Object obj = get(i);
 907             System.out.print(obj.getClass().getSimpleName());
 908             if(obj instanceof Token) {
 909                 Token t = (Token)obj;
 910                 System.out.print("(" + t.text + ")");
 911             }
 912             if(obj instanceof Symbol) {
 913                 Symbol s = (Symbol)obj;
 914                 System.out.print("["+ Locations.beginOf(s.location) + "-" + Locations.endOf(s.location) + "]");
 915             }
 916             System.out.print(" ");
 917         }
 918         System.out.println("-> " + reduced.getClass().getSimpleName() + " " +
 919                 Locations.beginOf(sym.location) + "-" + Locations.endOf(sym.location));*/
 920     }
 921
 922     @Override
 923     protected RuntimeException syntaxError(Token token, String description) {
 924         throw new SCLSyntaxErrorException(token.location, description);
 925     }
 926
 927     @Override
 928     protected Object reduceIdAccessor() {
 929         return new IdAccessor(((Token)get(0)).text);
 930     }
 931
 932     @Override
 933     protected Object reduceStringAccessor() {
 934         return new StringAccessor(((Token)get(1)).text);
 935     }
 936
 937     @Override
 938     protected Object reduceExpAccessor() {
 939         return new ExpressionAccessor((Expression)get(1));
 940     }
 941
 942     @Override
 943     protected Object reduceFieldAccess() {
 944         if(length() == 1)
 945             return get(0);
 946         FieldAccessor[] accessors = new FieldAccessor[length()/2];
 947         for(int i=0;i<accessors.length;++i) {
 948             FieldAccessor accessor = (FieldAccessor)get(i*2+2);
 949             accessor.accessSeparator = ((Token)get(i*2+1)).text.charAt(0);
 950             accessors[i] = accessor;
 951         }
 952         return new EFieldAccess((Expression)get(0), accessors);
 953     }
 954
 955     @Override
 956     protected Object reduceQueryBlock() {
 957         if(length() == 2)
 958             return Query.EMPTY_ARRAY;
 959         Query[] queries = new Query[length()/2];
 960         for(int i=0;i<queries.length;++i)
 961             queries[i] = (Query)get(2*i+1);
 962         return queries;
 963     }
 964
 965     @Override
 966     protected Object reduceGuardQuery() {
 967         return new QPreGuard((Expression)get(0));
 968     }
 969
 970     @Override
 971     protected Object reduceEqualsQuery() {
 972         return new QPreEquals((Expression)get(0), (Expression)get(2));
 973     }
 974
 975     @Override
 976     protected Object reduceBindQuery() {
 977         return new QPreBinds((Expression)get(0), (Expression)get(2));
 978     }
 979
 980     @Override
 981     protected Object reduceCompositeQuery() {
 982         Query[] queries = (Query[])get(1);
 983         switch(((Token)get(0)).text.charAt(1)) {
 984         case '&': return new QConjunction(queries);
 985         case '|': return new QDisjunction(queries);
 986         case '!': return new QNegation(new QConjunction(queries));
 987         case '?': return new QAlternative(queries);
 988         default: throw new InternalCompilerError();
 989         }
 990     }
 991
 992     @Override
 993     protected Object reduceRuleStatement() {
 994         return new RuleStatement((Expression)get(0), new QConjunction((Query[])get(2)));
 995     }
 996
 997     @Override
 998     protected Object reduceEntityTypeAnnotation() {
 999         return new EEntityTypeAnnotation((Expression)get(0), (Token)get(2),
1000                 length() > 3
1001                 ? new QConjunction((Query[])get(length()-1))
1002                 : null);
1003     }
1004
1005     @Override
1006     protected Object reduceHashedId() {
1007         return new EVar("#" + ((Token)get(1)).text);
1008     }
1009
1010     @Override
1011     protected Object reduceStringLiteral() {
1012         int expCount = length()/3;
1013         if(expCount == 0)
1014             return new ELiteral(new StringConstant(((Token)get(1)).text));
1015         else {
1016             String[] strings = new String[expCount+1];
1017             Expression[] expressions = new Expression[expCount];
1018             for(int i=0;i<expCount;++i) {
1019                 strings[i] = ((Token)get(i*3+1)).text;
1020                 expressions[i] = (Expression)get(i*3+2);
1021             }
1022             strings[expCount] = ((Token)get(expCount*3+1)).text;
1023             return new EStringLiteral(strings, expressions);
1024         }
1025     }
1026
1027     @Override
1028     protected Object reduceOneCommand() {
1029         return null;
1030     }
1031
1032     @Override
1033     protected Object reduceManyCommands() {
1034         return null;
1035     }
1036
1037     @Override
1038     protected Object reduceStatementCommand() {
1039         // to be extended in subclasses
1040         return null;
1041     }
1042
1043     @Override
1044     protected Object reduceImportCommand() {
1045         // to be extended in subclasses
1046         return null;
1047     }
1048
1049     @Override
1050     protected Object reduceImportValueItem() {
1051         return new EVar(((Token)get(0)).text);
1052     }
1053
1054     @Override
1055     protected Object reduceImportHiding() {
1056         EVar[] values = new EVar[(length()-2)/2];
1057         for(int i=0;i<values.length;++i)
1058             values[i] = (EVar)get(i*2+2);
1059         return new ImportDeclaration.ImportSpec(true, values);
1060     }
1061
1062     @Override
1063     protected Object reduceImportShowing() {
1064         EVar[] values = new EVar[(length()-1)/2];
1065         for(int i=0;i<values.length;++i)
1066             values[i] = (EVar)get(i*2+1);
1067         return new ImportDeclaration.ImportSpec(false, values);
1068     }
1069
1070     @Override
1071     protected Object reduceRuleDeclarations() {
1072         ArrayList<Object> declarations = new ArrayList<Object>(length()/2);
1073         for(int i=1;i<length();i+=2)
1074             declarations.add((Object)get(i));
1075         return declarations;
1076     }
1077
1078     private static final String[] EMPTY_STRING_ARRAY = new String[0];
1079
1080     @Override
1081     protected Object reduceRuleDefinition() {
1082         String[] extendsNames = EMPTY_STRING_ARRAY;
1083         if(length() >= 6) {
1084             int extendsCount = (length() - 4) / 2;
1085             extendsNames = new String[extendsCount];
1086             for(int i=0;i<extendsCount;++i)
1087                 extendsNames[i] = ((Token)get(3+i*2)).text;
1088         }
1089
1090         DRuleAst rule = new DRuleAst(
1091                 ((Token)get(0)).id == SCLTerminals.ABSTRACT_RULE,
1092                 ((Token)get(1)).text,
1093                 extendsNames);
1094
1095         ArrayList<Object> ruleDeclarations = (ArrayList<Object>)get(length()-1);
1096         ArrayList<Query> section = null;
1097         for(Object decl : ruleDeclarations) {
1098             if(decl instanceof DAnnotationAst) {
1099                 DAnnotationAst annotation = (DAnnotationAst)decl;
1100                 section = rule.getSection(annotation.id.text.substring(1));
1101             }
1102             else if(decl instanceof Query) {
1103                 if(section == null)
1104                     section = rule.getSection("when");
1105                 section.add((Query)decl);
1106             }
1107             else
1108                 throw new InternalCompilerError();
1109         }
1110         return rule;
1111     }
1112
1113     @Override
1114     protected Object reduceQueryRuleDeclaration() {
1115         return get(0);
1116     }
1117
1118     @Override
1119     protected Object reduceMappingRelationDefinition() {
1120         TypeAst[] types = new TypeAst[length()-2];
1121         for(int i=0;i<types.length;++i)
1122             types[i] = (TypeAst)get(i+2);
1123         return new DMappingRelationAst(
1124                 ((Token)get(1)).text,
1125                 types);
1126     }
1127
1128     @Override
1129     protected Object reduceTransformation() {
1130         return new ETransformation(
1131                 ((Token)get(1)).text,
1132                 new QConjunction((Query[])get(3))
1133                 );
1134     }
1135
1136     @Override
1137     protected Object reduceRelationDefinition() {
1138         return new DRelationAst((Expression)get(0),
1139                 ((ArrayList<Object>)get(2)).toArray());
1140     }
1141
1142     @Override
1143     protected Object reduceRecord() {
1144         FieldAssignment[] fields = new FieldAssignment[length()/2-1];
1145         for(int i=0;i<fields.length;++i)
1146             fields[i] = (FieldAssignment)get(2+i*2);
1147         return new ERecord((Token)get(0), fields);
1148     }
1149
1150     @Override
1151     protected Object reduceField() {
1152         return new FieldAssignment(((Token)get(0)).text, (Expression)get(2));
1153     }
1154
1155     @Override
1156     protected Object reduceFieldShorthand() {
1157         return new FieldAssignment(((Token)get(0)).text, null);
1158     }
1159
1160     @Override
1161     protected Object reduceRecordConstructor() {
1162         int idPos;
1163         for(idPos=0;idPos<length();idPos+=2)
1164             if(((Token)get(idPos)).id == SCLTerminals.ID)
1165                 break;
1166         DAnnotationAst[] annotations = idPos == 0 ? DAnnotationAst.EMPTY_ARRAY : new DAnnotationAst[idPos/2];
1167         for(int i=0;i<idPos/2;++i)
1168             annotations[i] = new DAnnotationAst((Token)get(i*2),
1169                     Arrays.asList((Expression)get(i*2+1)));
1170         TypeAst[] parameters = new TypeAst[(length()-idPos-1)/2];
1171         String[] fieldNames = new String[parameters.length];
1172         for(int i=0;i<parameters.length;++i) {
1173             FieldDescription fieldDesc = (FieldDescription)get(idPos+(i+1)*2);
1174             parameters[i] = fieldDesc.type;
1175             fieldNames[i] = fieldDesc.name;
1176         }
1177         return new ConstructorAst(annotations, ((Token)get(idPos)).text, parameters, fieldNames);
1178     }
1179
1180     @Override
1181     protected Object reduceFieldDescription() {
1182         return new FieldDescription(((Token)get(0)).text, (TypeAst)get(2));
1183     }
1184
1185     @Override
1186     protected Object reduceEq() {
1187         return (Expression)get(2);
1188     }
1189
1190     @Override
1191     protected Object reduceEquationBlock() {
1192         if(length() == 0)
1193             return new EEquations(Equation.EMPTY_ARRAY);
1194         Equation[] equations = new Equation[length()/2+1];
1195         for(int i=0;i<equations.length;++i)
1196             equations[i] = (Equation)get(2*i);
1197         return new EEquations(equations);
1198     }
1199
1200     @Override
1201     protected Object reduceGuardEquation() {
1202         return new EqGuard((Expression)get(0));
1203     }
1204
1205     @Override
1206     protected Object reduceBasicEquation() {
1207         return new EqBasic((Expression)get(0), (Expression)get(2));
1208     }
1209 }