bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ESelect.java

   1 package org.simantics.scl.compiler.elaboration.expressions;
   2
   3 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.Just;
   4 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.apply;
   5 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.let;
   6 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.loc;
   7 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.newVar;
   8 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.seq;
   9 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.tuple;
  10 import static org.simantics.scl.compiler.elaboration.expressions.Expressions.var;
  11
  12 import org.simantics.scl.compiler.common.exceptions.InternalCompilerError;
  13 import org.simantics.scl.compiler.common.names.Names;
  14 import org.simantics.scl.compiler.elaboration.contexts.SimplificationContext;
  15 import org.simantics.scl.compiler.elaboration.contexts.TranslationContext;
  16 import org.simantics.scl.compiler.elaboration.contexts.TypingContext;
  17 import org.simantics.scl.compiler.elaboration.query.QExists;
  18 import org.simantics.scl.compiler.elaboration.query.Query;
  19 import org.simantics.scl.compiler.elaboration.query.compilation.QueryCompilationContext;
  20 import org.simantics.scl.compiler.elaboration.query.compilation.QueryCompilationMode;
  21 import org.simantics.scl.compiler.elaboration.query.compilation.UnsolvableQueryException;
  22 import org.simantics.scl.compiler.errors.Locations;
  23 import org.simantics.scl.compiler.internal.parsing.parser.SCLTerminals;
  24 import org.simantics.scl.compiler.types.Type;
  25 import org.simantics.scl.compiler.types.Types;
  26 import org.simantics.scl.compiler.types.exceptions.MatchException;
  27 import org.simantics.scl.compiler.types.kinds.Kinds;
  28
  29 import gnu.trove.map.hash.TObjectIntHashMap;
  30 import gnu.trove.set.hash.THashSet;
  31 import gnu.trove.set.hash.TIntHashSet;
  32
  33 public class ESelect extends SimplifiableExpression {
  34
  35     private final Type ARRAY_LIST = Types.con("ArrayList", "T");
  36
  37     int selectVariant;
  38     Expression expression;
  39     Query query;
  40     Variable[] variables;
  41
  42     public ESelect(int selectVariant, Expression expression, Query query) {
  43         this.selectVariant = selectVariant;
  44         this.expression = expression;
  45         this.query = query;
  46     }
  47
  48     @Override
  49     public void collectVars(TObjectIntHashMap<Variable> allVars,
  50             TIntHashSet vars) {
  51         expression.collectVars(allVars, vars);
  52         query.collectVars(allVars, vars);
  53     }
  54
  55     @Override
  56     public void collectEffects(THashSet<Type> effects) {
  57         throw new InternalCompilerError(location, getClass().getSimpleName() + " does not support collectEffects.");
  58     }
  59
  60     @Override
  61     protected void updateType() throws MatchException {
  62         setType(selectVariant==SCLTerminals.SELECT_FIRST
  63                 ? Types.apply(Types.MAYBE, expression.getType())
  64                 : Types.list(expression.getType()));
  65     }
  66
  67     @Override
  68     public Expression checkBasicType(TypingContext context, Type requiredType) {
  69         Type componentType;
  70         switch(selectVariant) {
  71         case SCLTerminals.SELECT:
  72         case SCLTerminals.SELECT_DISTINCT:
  73             try {
  74                 componentType = Types.unifyApply(Types.LIST, requiredType);
  75             } catch (MatchException e) {
  76                 context.getErrorLog().log(location, "Select expression produces a list of values.");
  77                 return new EError(location);
  78             }
  79             break;
  80         case SCLTerminals.SELECT_FIRST:
  81             try {
  82                 componentType = Types.unifyApply(Types.MAYBE, requiredType);
  83             } catch (MatchException e) {
  84                 context.getErrorLog().log(location, "Select first expression produces an optional value.");
  85                 return new EError(location);
  86             }
  87             break;
  88         default: throw new InternalCompilerError();
  89         }
  90         for(Variable variable : variables)
  91             variable.setType(Types.metaVar(Kinds.STAR));
  92         expression.checkType(context, componentType);
  93         query.checkType(context);
  94
  95         // Compile query
  96         Type elType = expression.getType();
  97         Expression result;
  98         if(selectVariant == SCLTerminals.SELECT_FIRST) {
  99             QueryCompilationContext queryCompilationContext =
 100                     new QueryCompilationContext(context, QueryCompilationMode.GET_FIRST,
 101                             expression.getType(),
 102                             Just(expression));
 103             try {
 104                 new QExists(variables, query).generate(queryCompilationContext);
 105             } catch (UnsolvableQueryException e) {
 106                 context.getErrorLog().log(getLocation(), "Failed to compile the query.\n" + e.getMessage());
 107                 return new EError(getLocation());
 108             }
 109             result = queryCompilationContext.getContinuation();
 110         }
 111         else {
 112             Variable accumulator = newVar("accum", Types.apply(ARRAY_LIST, elType));
 113             result =
 114                     apply(context.getCompilationContext(), Types.PROC, Names.ArrayList_freeze, elType,
 115                             var(accumulator));
 116             Expression innerExpression =
 117                     apply(context.getCompilationContext(), Types.PROC, Names.ArrayList_add, elType,
 118                             var(accumulator), expression);
 119             try {
 120                 QueryCompilationContext queryCompilationContext =
 121                         new QueryCompilationContext(context, QueryCompilationMode.ITERATE, null, innerExpression);
 122                 new QExists(variables, query).generate(queryCompilationContext);
 123                 result = seq(queryCompilationContext.getContinuation(), result);
 124             } catch(UnsolvableQueryException e) {
 125                 context.getErrorLog().log(getLocation(), "Failed to compile the query.\n" + e.getMessage());
 126                 return new EError(getLocation());
 127             }
 128             result = let(accumulator,
 129                     apply(context.getCompilationContext(), Types.PROC, Names.ArrayList_new, elType, tuple()),
 130                     result
 131                     );
 132         }
 133         return loc(location, result);
 134     }
 135
 136     @Override
 137     public void collectFreeVariables(THashSet<Variable> vars) {
 138         expression.collectFreeVariables(vars);
 139         query.collectFreeVariables(vars);
 140         for(Variable variable : variables)
 141             vars.remove(variable);
 142     }
 143
 144     @Override
 145     public Expression resolve(TranslationContext context) {
 146         context.pushExistentialFrame();
 147         expression = expression.resolve(context);
 148         query = query.resolve(context);
 149         variables = context.popExistentialFrame();
 150         return this;
 151     }
 152
 153     @Override
 154     public void setLocationDeep(long loc) {
 155         if(location == Locations.NO_LOCATION) {
 156             location = loc;
 157             expression.setLocationDeep(loc);
 158             query.setLocationDeep(loc);
 159         }
 160     }
 161
 162     @Override
 163     public void accept(ExpressionVisitor visitor) {
 164         visitor.visit(this);
 165     }
 166
 167     @Override
 168     public Expression simplify(SimplificationContext context) {
 169         throw new UnsupportedOperationException();
 170     }
 171
 172     @Override
 173     public Expression accept(ExpressionTransformer transformer) {
 174         return transformer.transform(this);
 175     }
 176
 177 }