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