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