bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/macros/StandardMacroRule.java

   1 package org.simantics.scl.compiler.elaboration.macros;
   2
   3 import org.simantics.scl.compiler.elaboration.contexts.ReplaceContext;
   4 import org.simantics.scl.compiler.elaboration.contexts.SimplificationContext;
   5 import org.simantics.scl.compiler.elaboration.expressions.EApply;
   6 import org.simantics.scl.compiler.elaboration.expressions.ELambda;
   7 import org.simantics.scl.compiler.elaboration.expressions.ELambdaType;
   8 import org.simantics.scl.compiler.elaboration.expressions.ESimpleLambda;
   9 import org.simantics.scl.compiler.elaboration.expressions.Expression;
  10 import org.simantics.scl.compiler.elaboration.expressions.Variable;
  11 import org.simantics.scl.compiler.types.TVar;
  12 import org.simantics.scl.compiler.types.Type;
  13
  14 import gnu.trove.map.hash.THashMap;
  15
  16 /**
  17  * This is a macro rule that replaces an application with
  18  * the definition of the function.
  19  * @author Hannu Niemist&ouml;
  20  */
  21 public class StandardMacroRule implements MacroRule {
  22     Expression baseExpression;
  23     int arity;
  24
  25     public StandardMacroRule() {
  26     }
  27
  28     public void setBaseExpression(Expression baseExpression) {
  29         this.baseExpression = baseExpression;
  30
  31         Expression cur = baseExpression;
  32         while(true) {
  33             if(cur instanceof ELambdaType) {
  34                 cur = ((ELambdaType)cur).value;
  35             }
  36             else if(cur instanceof ELambda) {
  37                 ELambda lambda = (ELambda)cur;
  38                 arity += lambda.getCases()[0].getPatterns().length;
  39                 break;
  40             }
  41             else if(cur instanceof ESimpleLambda) {
  42                 ESimpleLambda lambda = (ESimpleLambda)cur;
  43                 cur = lambda.value;
  44                 ++arity;
  45             }
  46             else
  47                 break;
  48         }
  49     }
  50
  51     @Override
  52     public Expression apply(SimplificationContext context,
  53             Type[] typeParameters, EApply apply) {
  54         if(apply.getParameters().length < arity)
  55             return null;
  56         THashMap<TVar, Type> tvarMap = new THashMap<TVar, Type>();
  57         THashMap<Variable, Expression> varMap = new THashMap<Variable, Expression>();
  58
  59         Expression baseExpr = baseExpression;
  60         /*System.out.println(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>");
  61         TypeUnparsingContext tuc = new TypeUnparsingContext();
  62         System.out.println("initial1 = " + baseExpr.toString(tuc));
  63         */
  64         {
  65             int typeParameterId = 0;
  66             while(typeParameterId < typeParameters.length) {
  67                 ELambdaType lambda = (ELambdaType)baseExpr;
  68                 for(TVar var : lambda.parameters)
  69                     tvarMap.put(var, typeParameters[typeParameterId++]);
  70                 baseExpr = lambda.value;
  71             }
  72         }
  73         for(Expression parameter : apply.getParameters()) {
  74             if(baseExpr instanceof ELambda)
  75                 baseExpr = ((ELambda)baseExpr).decomposeMatching();
  76             ESimpleLambda lambda = (ESimpleLambda)baseExpr;
  77             varMap.put(lambda.parameter, parameter);
  78             baseExpr = lambda.value;
  79         }
  80
  81         /*
  82
  83         System.out.println("initial2 = " + baseExpr.toString(tuc));
  84
  85         System.out.print("tvarMap={");
  86         boolean first = true;
  87         for(Map.Entry<TVar, Type> entry : tvarMap.entrySet()) {
  88             if(first)
  89                 first = false;
  90             else
  91                 System.out.print(", ");
  92             System.out.print(entry.getKey().toString(tuc));
  93             System.out.print(" = ");
  94             System.out.print(entry.getValue().toString(tuc));
  95         }
  96         System.out.println("}");
  97         System.out.println("varMap = " + varMap);
  98         */
  99         baseExpr = baseExpr.replace(new ReplaceContext(tvarMap, varMap, null));
 100
 101         //System.out.println("final = " + baseExpr.toString(tuc));
 102
 103         return baseExpr;
 104     }
 105
 106 }