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