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

   1 package org.simantics.scl.compiler.elaboration.expressions;
   2
   3 import java.util.List;
   4
   5 import org.simantics.scl.compiler.common.names.Names;
   6 import org.simantics.scl.compiler.constants.Constant;
   7 import org.simantics.scl.compiler.elaboration.contexts.SimplificationContext;
   8 import org.simantics.scl.compiler.elaboration.contexts.TranslationContext;
   9 import org.simantics.scl.compiler.elaboration.contexts.TypingContext;
  10 import org.simantics.scl.compiler.elaboration.expressions.EAmbiguous.Alternative;
  11 import org.simantics.scl.compiler.elaboration.expressions.accessor.FieldAccessor;
  12 import org.simantics.scl.compiler.elaboration.expressions.accessor.IdAccessor;
  13 import org.simantics.scl.compiler.errors.Locations;
  14 import org.simantics.scl.compiler.internal.header.ModuleHeader;
  15 import org.simantics.scl.compiler.types.Type;
  16 import org.simantics.scl.compiler.types.Types;
  17 import org.simantics.scl.compiler.types.exceptions.MatchException;
  18
  19 import gnu.trove.map.hash.TObjectIntHashMap;
  20 import gnu.trove.set.hash.THashSet;
  21 import gnu.trove.set.hash.TIntHashSet;
  22
  23 public class EFieldAccess extends SimplifiableExpression {
  24
  25     private static final Type VARIABLE = Types.con("Simantics/Variables", "Variable");
  26
  27     Expression parent;
  28     FieldAccessor accessor;
  29     boolean lastAccessor = true;
  30
  31     public EFieldAccess(Expression parent, FieldAccessor accessor) {
  32         this.parent = parent;
  33         this.accessor = accessor;
  34         if(parent instanceof EFieldAccess)
  35                 ((EFieldAccess)parent).lastAccessor = false;
  36     }
  37
  38     @Override
  39     public void collectRefs(TObjectIntHashMap<Object> allRefs,
  40             TIntHashSet refs) {
  41         parent.collectRefs(allRefs, refs);
  42         accessor.collectRefs(allRefs, refs);
  43     }
  44
  45     @Override
  46     public void collectVars(TObjectIntHashMap<Variable> allVars,
  47             TIntHashSet vars) {
  48         parent.collectVars(allVars, vars);
  49         accessor.collectVars(allVars, vars);
  50     }
  51
  52     private boolean returnsValue() {
  53         return accessor.accessSeparator == '#' && !accessor.isVariableId();
  54     }
  55
  56     @Override
  57     protected void updateType() throws MatchException {
  58         // Type is already updated in checkBasicType
  59     }
  60
  61     private Expression resolveAccessor(TypingContext context, Type requiredType) {
  62         if(!(accessor instanceof IdAccessor))
  63             return null;
  64         IdAccessor idAccessor = (IdAccessor)accessor;
  65         if(idAccessor.accessSeparator != '.')
  66             return null;
  67         List<Constant> accessors = context.getEnvironment().getFieldAccessors(idAccessor.fieldName);
  68         if(accessors == null) {
  69             context.getErrorLog().log(idAccessor.location, "Couldn't resolve accessor ." + idAccessor.fieldName + ".");
  70             return new EError(location);
  71         }
  72         Expression accessorExpression;
  73         if(accessors.size() == 1)
  74             accessorExpression = new ELiteral(accessors.get(0));
  75         else {
  76             Alternative[] alternatives = new Alternative[accessors.size()];
  77             for(int i=0;i<alternatives.length;++i) {
  78                 final int index = i;
  79                 alternatives[i] = new Alternative() {
  80                     @Override
  81                     public Expression realize() {
  82                         return new ELiteral(accessors.get(index));
  83                     }
  84                     @Override
  85                     public Type getType() {
  86                         return accessors.get(index).getType();
  87                     }
  88                     @Override
  89                     public String toString() {
  90                         return accessors.get(index).toString();
  91                     }
  92                 };
  93             }
  94             accessorExpression = new EAmbiguous(alternatives);
  95             accessorExpression.location = location;
  96         }
  97         return new EApply(location, accessorExpression, parent).checkType(context, requiredType);
  98     }
  99
 100     @Override
 101     public Expression checkBasicType(TypingContext context, Type requiredType) {
 102         ModuleHeader header = context.getCompilationContext().header;
 103         if(header != null && header.fields) {
 104             Expression expression = resolveAccessor(context, requiredType);
 105             if(expression != null)
 106                 return expression;
 107         }
 108
 109         // Default case
 110         if(returnsValue())
 111             setType(requiredType);
 112         else {
 113             setType(VARIABLE);
 114             context.subsume(this, requiredType);
 115         }
 116         parent = parent.checkType(context, VARIABLE);
 117         accessor.checkType(context);
 118         context.declareEffect(getLocation(), Types.READ_GRAPH);
 119         return this;
 120     }
 121
 122     @Override
 123     public void collectFreeVariables(THashSet<Variable> vars) {
 124         parent.collectFreeVariables(vars);
 125         accessor.collectFreeVariables(vars);
 126     }
 127
 128     @Override
 129     public Expression simplify(SimplificationContext context) {
 130         // Simplify subexpressions
 131         parent = parent.simplify(context);
 132         accessor.simplify(context);
 133
 134         if(accessor.accessSeparator == '.')
 135                 return new EApply(
 136                                 getLocation(),
 137                                 Types.READ_GRAPH,
 138                                 context.getConstant(Names.Simantics_Variables_child_),
 139                                 parent,
 140                                 accessor.asExpression()
 141                                 );
 142         else if(!lastAccessor)
 143                 return new EApply(
 144                                 getLocation(),
 145                                 Types.READ_GRAPH,
 146                                 context.getConstant(Names.Simantics_Variables_property),
 147                                 parent,
 148                                 accessor.asExpression()
 149                                 );
 150         else if(accessor.isVariableId())
 151                 return parent;
 152         else
 153                 return new EApply(
 154                                 getLocation(),
 155                                 Types.READ_GRAPH,
 156                                 context.getConstant(Names.Simantics_Variables_untypedPropertyValue, getType()),
 157                                 parent,
 158                                 accessor.asExpression()
 159                                 );
 160     }
 161
 162     @Override
 163     public Expression resolve(TranslationContext context) {
 164         parent = parent.resolve(context);
 165         accessor.resolve(context);
 166         return this;
 167     }
 168
 169     @Override
 170     public void collectEffects(THashSet<Type> effects) {
 171         // FIXME
 172         effects.add(Types.READ_GRAPH);
 173     }
 174
 175     @Override
 176     public void setLocationDeep(long loc) {
 177         if(location == Locations.NO_LOCATION) {
 178             location = loc;
 179             parent.setLocationDeep(loc);
 180             accessor.setLocationDeep(loc);
 181         }
 182     }
 183
 184     @Override
 185     public void accept(ExpressionVisitor visitor) {
 186         visitor.visit(this);
 187     }
 188
 189     @Override
 190     public void forVariables(VariableProcedure procedure) {
 191         parent.forVariables(procedure);
 192         accessor.forVariables(procedure);
 193     }
 194
 195     @Override
 196     public Expression accept(ExpressionTransformer transformer) {
 197         return transformer.transform(this);
 198     }
 199
 200 }