bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/contexts/TranslationContext.java

   1 package org.simantics.scl.compiler.elaboration.contexts;
   2
   3 import java.util.ArrayList;
   4 import java.util.Arrays;
   5
   6 import org.simantics.scl.compiler.common.names.Name;
   7 import org.simantics.scl.compiler.common.precedence.Associativity;
   8 import org.simantics.scl.compiler.common.precedence.Precedence;
   9 import org.simantics.scl.compiler.compilation.CompilationContext;
  10 import org.simantics.scl.compiler.elaboration.chr.CHRRuleset;
  11 import org.simantics.scl.compiler.elaboration.chr.relations.CHRConstraint;
  12 import org.simantics.scl.compiler.elaboration.expressions.Case;
  13 import org.simantics.scl.compiler.elaboration.expressions.EAmbiguous;
  14 import org.simantics.scl.compiler.elaboration.expressions.EConstant;
  15 import org.simantics.scl.compiler.elaboration.expressions.EError;
  16 import org.simantics.scl.compiler.elaboration.expressions.EFieldAccess;
  17 import org.simantics.scl.compiler.elaboration.expressions.ELambda;
  18 import org.simantics.scl.compiler.elaboration.expressions.EVar;
  19 import org.simantics.scl.compiler.elaboration.expressions.EVariable;
  20 import org.simantics.scl.compiler.elaboration.expressions.Expression;
  21 import org.simantics.scl.compiler.elaboration.expressions.Variable;
  22 import org.simantics.scl.compiler.elaboration.expressions.accessor.FieldAccessor;
  23 import org.simantics.scl.compiler.elaboration.expressions.accessor.IdAccessor;
  24 import org.simantics.scl.compiler.elaboration.expressions.block.LetStatement;
  25 import org.simantics.scl.compiler.elaboration.modules.SCLValue;
  26 import org.simantics.scl.compiler.elaboration.query.pre.PreQuery;
  27 import org.simantics.scl.compiler.elaboration.relations.SCLRelation;
  28 import org.simantics.scl.compiler.environment.AmbiguousNameException;
  29 import org.simantics.scl.compiler.environment.Environments;
  30 import org.simantics.scl.compiler.environment.LocalEnvironment;
  31 import org.simantics.scl.compiler.environment.Namespace;
  32 import org.simantics.scl.compiler.environment.filter.AcceptAllNamespaceFilter;
  33 import org.simantics.scl.compiler.errors.Locations;
  34 import org.simantics.scl.compiler.internal.parsing.declarations.DValueAst;
  35 import org.simantics.scl.compiler.module.debug.ModuleDebugInfo;
  36 import org.simantics.scl.compiler.module.debug.SymbolReference;
  37 import org.simantics.scl.compiler.top.SCLCompilerConfiguration;
  38 import org.simantics.scl.compiler.types.Type;
  39
  40 import gnu.trove.list.array.TIntArrayList;
  41 import gnu.trove.map.hash.THashMap;
  42 import gnu.trove.procedure.TObjectProcedure;
  43 import gnu.trove.set.hash.THashSet;
  44
  45 public class TranslationContext extends TypeTranslationContext implements EnvironmentalContext {
  46
  47     public static class ExistentialFrame {
  48         THashSet<String> variables = new THashSet<String>(4);
  49         ArrayList<Variable> blanks = new ArrayList<Variable>(2);
  50         public boolean disallowNewExistentials;
  51
  52         public EVariable createBlank(long location) {
  53             Variable variable = new Variable("_");
  54             blanks.add(variable);
  55             EVariable result = new EVariable(variable);
  56             result.location = location;
  57             return result;
  58         }
  59     }
  60
  61     THashMap<String, Variable> variables = new THashMap<String, Variable>();
  62     ArrayList<Entry> variableEntries = new ArrayList<Entry>();
  63     LocalEnvironment localEnvironment;
  64     TIntArrayList frames = new TIntArrayList();
  65     ArrayList<THashSet<String>> frameNameSets = new ArrayList<THashSet<String>>();
  66     ArrayList<ExistentialFrame> existentialFrames = new ArrayList<ExistentialFrame>(2);
  67     SCLValue bindFunction;
  68
  69     public PreQuery currentPreQuery;
  70
  71     THashMap<String, SCLRelation> relations = new THashMap<String, SCLRelation>();
  72     TIntArrayList relationFrames = new TIntArrayList();
  73     ArrayList<RelationEntry> relationEntries = new ArrayList<RelationEntry>();
  74
  75     THashMap<String, CHRConstraint> chrConstraints = new THashMap<String, CHRConstraint>();
  76     TIntArrayList chrConstraintFrames = new TIntArrayList();
  77     ArrayList<CHRConstraintEntry> chrConstraintEntries = new ArrayList<CHRConstraintEntry>();
  78
  79     public CHRRuleset currentRuleset;
  80
  81     public ModuleDebugInfo moduleDebugInfo;
  82
  83     private String definitionName;
  84
  85     static class Entry {
  86         String name;
  87         Variable variable;
  88         public Entry(String name, Variable variable) {
  89             this.name = name;
  90             this.variable = variable;
  91         }
  92     }
  93
  94     static class RelationEntry {
  95         String name;
  96         SCLRelation relation;
  97         public RelationEntry(String name, SCLRelation relation) {
  98             this.name = name;
  99             this.relation = relation;
 100         }
 101     }
 102
 103     static class CHRConstraintEntry {
 104         String name;
 105         CHRConstraint constraint;
 106         public CHRConstraintEntry(String name, CHRConstraint constraint) {
 107             this.name = name;
 108             this.constraint = constraint;
 109         }
 110     }
 111
 112     public TranslationContext(CompilationContext compilationContext, LocalEnvironment localEnvironment, String definitionName) {
 113         super(compilationContext);
 114         this.localEnvironment = localEnvironment;
 115         this.moduleDebugInfo = compilationContext.moduleDebugInfo;
 116         this.definitionName = definitionName;
 117     }
 118
 119     public static boolean isConstructorName(String name) {
 120         int p = name.lastIndexOf('.');
 121         char firstChar = name.charAt(p<0 ? 0 : p+1);
 122         return Character.isUpperCase(firstChar) || firstChar == '(';
 123     }
 124
 125     /* Tries to resolve name as a local variable. It is assumed
 126      * that name does not contain '.'.
 127      */
 128     private Expression resolveLocalVariable(long location, String name) {
 129         Variable variable = variables.get(name);
 130         if(variable != null)
 131             return new EVariable(location, variable);
 132
 133         char c = name.charAt(0);
 134         switch(c) {
 135         case '?': {
 136             ExistentialFrame existentialFrame = getCurrentExistentialFrame();
 137             if(existentialFrame == null || existentialFrame.disallowNewExistentials) {
 138                 errorLog.log(location, "New existential variables can be defined only in queries.");
 139                 return new EError(location);
 140             }
 141             variable = new Variable(name);
 142             variables.put(name, variable);
 143             existentialFrame.variables.add(name);
 144             return new EVariable(variable);
 145         }
 146         case '_': {
 147             if(name.length()==1) {
 148                 ExistentialFrame existentialFrame = getCurrentExistentialFrame();
 149                 if(existentialFrame == null || existentialFrame.disallowNewExistentials) {
 150                     errorLog.log(location, "Blank variables can be used only in queries.");
 151                     return new EError(location);
 152                 }
 153                 return existentialFrame.createBlank(location);
 154             }
 155             break;
 156         }
 157         }
 158         return null;
 159     }
 160
 161     public ExistentialFrame getCurrentExistentialFrame() {
 162         int size = existentialFrames.size();
 163         if(size == 0)
 164             return null;
 165         else
 166             return existentialFrames.get(size-1);
 167     }
 168
 169     private Expression resolveFieldAccess(long location, Expression base, int pos, String name) {
 170         while(pos != -1) {
 171             int p = findSeparator(name, pos+1);
 172             int endPos = p==-1 ? name.length() : p;
 173             FieldAccessor accessor = new IdAccessor(
 174                     name.charAt(pos),
 175                     name.substring(pos+1, endPos));
 176             accessor.location = Locations.sublocation(location, pos+1, endPos);
 177             base = new EFieldAccess(base, accessor);
 178             base.location = Locations.sublocation(location, 0, endPos);
 179             pos = p;
 180         }
 181         return base;
 182     }
 183
 184     private static int findSeparator(String name, int fromIndex) {
 185         ++fromIndex; // the first character (that can be #) is never a separator
 186         while(fromIndex < name.length()) {
 187             char c = name.charAt(fromIndex);
 188             if(c == '.' || c == '#')
 189                 return fromIndex;
 190             ++fromIndex;
 191         }
 192         return -1;
 193     }
 194
 195     public Expression resolveValue(long location, Namespace namespace, String name) {
 196         try {
 197             SCLValue value = namespace.getValue(name);
 198             if(value == null)
 199                 return null;
 200             String deprecatedDescription = value.isDeprecated();
 201             if(deprecatedDescription != null)
 202                 errorLog.logWarning(location, "Deprecated value " + value.getName().name + "." + (deprecatedDescription.isEmpty() ? "" : " " + deprecatedDescription));
 203             if(moduleDebugInfo != null)
 204                 moduleDebugInfo.symbolReferences.add(new SymbolReference(value.getName(), Name.create(compilationContext.module.getName(), definitionName), location));
 205             return new EConstant(location, value);
 206         } catch (AmbiguousNameException e) {
 207             if(SCLCompilerConfiguration.ALLOW_OVERLOADING)
 208                 return resolveAmbigious(location, e.conflictingModules, name);
 209             else {
 210                 errorLog.log(location, e.getMessage());
 211                 return new EError(location);
 212             }
 213         }
 214     }
 215
 216     private Expression resolveAmbigious(long location, String[] conflictingModules, String name) {
 217         EAmbiguous.Alternative[] alternatives = new EAmbiguous.Alternative[conflictingModules.length];
 218         for(int i=0;i<conflictingModules.length;++i) {
 219             Name altName = Name.create(conflictingModules[i], name);
 220             SCLValue altValue = environment.getValue(altName);
 221             alternatives[i] = new EAmbiguous.Alternative() {
 222                 @Override
 223                 public Type getType() {
 224                     return altValue.getType();
 225                 }
 226
 227                 @Override
 228                 public Expression realize() {
 229                     EConstant expression = new EConstant(altValue);
 230                     expression.location = location;
 231                     if(moduleDebugInfo != null)
 232                         moduleDebugInfo.symbolReferences.add(new SymbolReference(altValue.getName(), Name.create(compilationContext.module.getName(), definitionName), location));
 233                     return expression;
 234                 }
 235
 236                 @Override
 237                 public String toString() {
 238                     return altValue.getName().toString().replace('/', '.');
 239                 }
 240             };
 241         }
 242         EAmbiguous expression = new EAmbiguous(alternatives);
 243         expression.location = location;
 244         return expression;
 245     }
 246
 247     public Expression resolveVariable(long location, Namespace namespace, String name, int begin) {
 248         int end = findSeparator(name, begin);
 249         String part = end == -1 ? (begin == 0 ? name : name.substring(begin)) : name.substring(begin, end);
 250
 251         if(begin == 0) {
 252             Expression result = resolveLocalVariable(location, part);
 253             if(result != null)
 254                 return end == -1 ? result : resolveFieldAccess(location, result, end, name);
 255
 256             // FIXME.. support for records
 257             if(localEnvironment != null) {
 258                 result = localEnvironment.resolve(environment, name);
 259                 if(result != null) {
 260                     result.setLocationDeep(location);
 261                     return result;
 262                 }
 263             }
 264         }
 265         if(end != -1 && name.charAt(end) == '.') {
 266             Namespace childNamespace = namespace.getNamespace(part);
 267             if(childNamespace != null)
 268                 return resolveVariable(location, childNamespace, name, end+1);
 269         }
 270         {
 271             Expression result = null;
 272             if(end != -1) {
 273                 for(int end2 = name.length();end2 > end;end2 = name.lastIndexOf('.', end2-1)) {
 274                     part = name.substring(begin, end2);
 275                     result = resolveValue(location, namespace, part);
 276                     if(result != null) {
 277                         end = end2 == name.length() ? -1 : end2;
 278                         break;
 279                     }
 280                 }
 281             }
 282             if(result == null)
 283                 result = resolveValue(location, namespace, part);
 284             if(result != null)
 285                 return end == -1 ? result : resolveFieldAccess(location, result, end, name);
 286         }
 287         reportResolveFailure(location, namespace, part);
 288         return new EError(location);
 289     }
 290
 291     private void reportResolveFailure(long location, Namespace namespace, String name) {
 292         StringBuilder message = new StringBuilder();
 293         message.append("Couldn't resolve ").append(name).append(".");
 294
 295         final THashSet<String> candidateNames = new THashSet<String>(4);
 296         namespace.findValuesForPrefix("", AcceptAllNamespaceFilter.INSTANCE,
 297                 new TObjectProcedure<SCLValue>() {
 298             @Override
 299             public boolean execute(SCLValue value) {
 300                 if(value == null) {
 301                     new Exception().printStackTrace();
 302                     return true;
 303                 }
 304                 String valueName = value.getName().name;
 305                 if(name.equalsIgnoreCase(valueName))
 306                     candidateNames.add(valueName);
 307                 return true;
 308             }
 309         });
 310         if(localEnvironment != null)
 311             localEnvironment.forNames(new TObjectProcedure<String>() {
 312                 @Override
 313                 public boolean execute(String valueName) {
 314                     if(name.equalsIgnoreCase(valueName))
 315                         candidateNames.add(valueName);
 316                     return true;
 317                 }
 318             });
 319
 320         if(candidateNames.size() > 0) {
 321             message.append(" Did you mean ");
 322             String[] ns = candidateNames.toArray(new String[candidateNames.size()]);
 323             Arrays.sort(ns);
 324             for(int i=0;i<ns.length;++i) {
 325                 if(i > 0) {
 326                     message.append(", ");
 327                     if(i == ns.length-1)
 328                         message.append("or ");
 329                 }
 330                 message.append(ns[i]);
 331             }
 332             message.append('?');
 333         }
 334
 335         errorLog.log(location, message.toString());
 336     }
 337
 338     public Expression resolveVariable(long location, String name) {
 339         return resolveVariable(location, environment.getLocalNamespace(), name, 0);
 340     }
 341
 342     public Expression resolvePattern(EVar name) {
 343         char firstChar = name.name.charAt(0);
 344         if(firstChar == '_' && name.name.length()==1) {
 345             return new EVariable(new Variable("_"));
 346         }
 347         else if(!Character.isUpperCase(firstChar)) {
 348             if(!frameNameSets.get(frameNameSets.size()-1).add(name.name))
 349                 errorLog.log(name.location, "Repeated variable "+name.name+" in pattern.");
 350             return new EVariable(name.location, newVariable(name.name));
 351         }
 352         else
 353             return resolveVariable(name.location, name.name);
 354     }
 355
 356     /**
 357      * Starts a new environment frame. New variables defined in this frame shadow
 358      * the old variables and when the frame is popped, the old variables are again
 359      * visible.
 360      */
 361     public void pushFrame() {
 362         frames.add(variableEntries.size());
 363         frameNameSets.add(new THashSet<String>());
 364     }
 365
 366     /**
 367      * Ends an environment frame. See {@link #pushFrame}.
 368      */
 369     public void popFrame() {
 370         int frame = frames.removeAt(frames.size()-1);
 371         int i = variableEntries.size();
 372         while(i > frame) {
 373             --i;
 374             Entry entry = variableEntries.remove(i);
 375             if(entry.variable == null)
 376                 variables.remove(entry.name);
 377             else
 378                 variables.put(entry.name, entry.variable);
 379         }
 380         frameNameSets.remove(frameNameSets.size()-1);
 381     }
 382
 383     public void pushRelationFrame() {
 384         relationFrames.add(relationEntries.size());
 385     }
 386
 387     public void popRelationFrame() {
 388         int frame = relationFrames.removeAt(relationFrames.size()-1);
 389         int i = relationEntries.size();
 390         while(i > frame) {
 391             --i;
 392             RelationEntry entry = relationEntries.remove(i);
 393             if(entry.relation == null)
 394                 relations.remove(entry.name);
 395             else
 396                 relations.put(entry.name, entry.relation);
 397         }
 398     }
 399
 400     public void pushCHRConstraintFrame() {
 401         chrConstraintFrames.add(chrConstraintEntries.size());
 402     }
 403
 404     public void popCHRConstraintFrame(CHRRuleset ruleset) {
 405         int frame = chrConstraintFrames.removeAt(chrConstraintFrames.size()-1);
 406         int i = chrConstraintEntries.size();
 407         while(i > frame) {
 408             --i;
 409             CHRConstraintEntry entry = chrConstraintEntries.remove(i);
 410             CHRConstraint newConstraint;
 411             if(entry.constraint == null)
 412                 newConstraint = chrConstraints.remove(entry.name);
 413             else
 414                 newConstraint = chrConstraints.put(entry.name, entry.constraint);
 415             if(newConstraint.implicitlyDeclared)
 416                 ruleset.addConstraint(newConstraint);
 417         }
 418     }
 419
 420     public void pushExistentialFrame() {
 421         pushFrame();
 422         existentialFrames.add(new ExistentialFrame());
 423     }
 424
 425     public Variable[] popExistentialFrame() {
 426         popFrame();
 427         ExistentialFrame frame = existentialFrames.remove(existentialFrames.size()-1);
 428         Variable[] result = new Variable[frame.variables.size() + frame.blanks.size()];
 429         int i=0;
 430         for(String name : frame.variables)
 431             result[i++] = variables.remove(name);
 432         for(Variable blank : frame.blanks)
 433             result[i++] = blank;
 434         return result;
 435     }
 436
 437     public Variable newVariable(String name) {
 438         Variable variable = new Variable(name);
 439         Variable oldVariable = variables.put(name, variable);
 440         variableEntries.add(new Entry(name, oldVariable));
 441         return variable;
 442     }
 443
 444     public THashMap<String, Variable> getVariables() {
 445         return variables;
 446     }
 447
 448     public void newRelation(String name, SCLRelation relation) {
 449         SCLRelation oldRelation = relations.put(name, relation);
 450         relationEntries.add(new RelationEntry(name, oldRelation));
 451     }
 452
 453     public void newCHRConstraint(String name, CHRConstraint constraint) {
 454         CHRConstraint oldConstraint = chrConstraints.put(name, constraint);
 455         chrConstraintEntries.add(new CHRConstraintEntry(name, oldConstraint));
 456     }
 457
 458     public Precedence getPrecedence(Name op) {
 459         Precedence prec = environment.getValue(op).getPrecedence();
 460         if(prec == null)
 461             return new Precedence(1, Associativity.NONASSOC);
 462         else
 463             return prec;
 464     }
 465
 466     public Case translateCase(Expression lhs, Expression rhs) {
 467         ArrayList<Expression> parameters = new ArrayList<Expression>(4);
 468         lhs.getParameters(this, parameters);
 469         Expression[] patterns = new Expression[parameters.size()];
 470         pushFrame();
 471         for(int i=0;i<patterns.length;++i) {
 472             Expression pattern = parameters.get(i);
 473             pattern = pattern.resolveAsPattern(this);
 474             patterns[i] = pattern;
 475         }
 476         rhs = rhs.resolve(this);
 477         popFrame();
 478         Case case_ = new Case(patterns, rhs);
 479         case_.setLhs(lhs.location);
 480         return case_;
 481     }
 482
 483     public Expression translateCases2(ArrayList<DValueAst> definitions) {
 484         Case[] cases = new Case[definitions.size()];
 485         for(int i=0;i<cases.length;++i) {
 486             DValueAst def = definitions.get(i);
 487             cases[i] = translateCase(def.lhs, def.value);
 488         }
 489         // check arity consistency
 490         int arity = cases[0].patterns.length;
 491         for(int i=1;i<cases.length;++i)
 492             if(cases[i].patterns.length != arity)
 493                 errorLog.log(definitions.get(i).lhs.location,
 494                         "Inconsistent arity. " +
 495                         "This case has arity " + cases[i].patterns.length +
 496                                 " while previous cases had arity " + arity + ".");
 497         if(cases.length == 1 && cases[0].patterns.length == 0)
 498             return cases[0].value;
 499         else
 500             return new ELambda(
 501                     Locations.combine(definitions.get(0).location, definitions.get(definitions.size()-1).location),
 502                     cases);
 503     }
 504
 505     public Expression translateCases(ArrayList<LetStatement> definitions) {
 506         Case[] cases = new Case[definitions.size()];
 507         for(int i=0;i<cases.length;++i) {
 508             LetStatement def = definitions.get(i);
 509             cases[i] = translateCase(def.pattern, def.value);
 510         }
 511         // check arity concistency
 512         int arity = cases[0].patterns.length;
 513         for(int i=1;i<cases.length;++i)
 514             if(cases[i].patterns.length != arity)
 515                 errorLog.log(definitions.get(i).pattern.location,
 516                         "Inconsistent arity. " +
 517                         "This case has arity " + cases[i].patterns.length +
 518                         " while previous cases had arity " + arity + ".");
 519         if(arity == 0) {
 520             if(cases.length > 1)
 521                 errorLog.log(cases[1].value.location, "Cannot give multiple cases for arity 0 function.");
 522             return cases[0].value;
 523         }
 524         return new ELambda(
 525                 Locations.combine(definitions.get(0).location, definitions.get(definitions.size()-1).location),
 526                 cases);
 527     }
 528
 529     public SCLRelation resolveRelation(long location, String name) {
 530         SCLRelation relation = relations.get(name);
 531         if(relation != null)
 532             return relation;
 533
 534         try {
 535             relation = Environments.getRelation(environment, name);
 536             /*if(relation == null) {
 537                 errorLog.log(location, "Couldn't resolve relation " + name + ".");
 538                 return null;
 539             }*/
 540             return relation;
 541         } catch (AmbiguousNameException e) {
 542             errorLog.log(location, e.getMessage());
 543             return null;
 544         }
 545     }
 546
 547     public CHRConstraint resolveCHRConstraint(String name) {
 548         return chrConstraints.get(name);
 549     }
 550
 551     @Override
 552     public SCLValue getValue(Name name) {
 553         return environment.getValue(name);
 554     }
 555
 556     public CHRRuleset resolveRuleset(String name) throws AmbiguousNameException {
 557         return Environments.getRuleset(environment, name);
 558     }
 559
 560     public void disallowNewExistentials() {
 561         getCurrentExistentialFrame().disallowNewExistentials = true;
 562     }
 563 }