bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/internal/interpreted/ILambda.java

   1 package org.simantics.scl.compiler.internal.interpreted;
   2
   3 import org.simantics.scl.runtime.function.FunctionImpl1;
   4 import org.simantics.scl.runtime.function.FunctionImpl2;
   5 import org.simantics.scl.runtime.function.FunctionImpl3;
   6 import org.simantics.scl.runtime.function.FunctionImpl4;
   7 import org.simantics.scl.runtime.function.FunctionImplN;
   8
   9 public class ILambda implements IExpression {
  10     private final int[] inheritedVariableIds;
  11     private final int arity;
  12     private final int variableBindingsLength;
  13     private final IExpression body;
  14
  15     public ILambda(int[] inheritedVariableIds, int arity,
  16             int variableBindingsLength, IExpression body) {
  17         this.inheritedVariableIds = inheritedVariableIds;
  18         this.arity = arity;
  19         this.variableBindingsLength = variableBindingsLength;
  20         this.body = body;
  21     }
  22
  23     @SuppressWarnings("rawtypes")
  24     @Override
  25     public Object execute(Object[] variableBindings) {
  26         final Object[] inheritedVariableBindings = new Object[inheritedVariableIds.length];
  27         for(int i=0;i<inheritedVariableIds.length;++i)
  28             inheritedVariableBindings[i] = variableBindings[inheritedVariableIds[i]];
  29         switch(arity) {
  30         case 1:
  31             return new FunctionImpl1() {
  32                 @Override
  33                 public Object apply(Object param0) {
  34                     Object[] newVariableBindings = new Object[variableBindingsLength];
  35                     int i = 0;;
  36                     for(;i < inheritedVariableBindings.length;++i)
  37                         newVariableBindings[i] = inheritedVariableBindings[i];
  38                     newVariableBindings[i] = param0;
  39                     return body.execute(newVariableBindings);
  40                 }
  41
  42                 @Override
  43                 public String toString() {
  44                         return ILambda.this.toString(inheritedVariableBindings);
  45                 }
  46             };
  47         case 2:
  48             return new FunctionImpl2() {
  49                 @Override
  50                 public Object apply(Object param0, Object param1) {
  51                     Object[] newVariableBindings = new Object[variableBindingsLength];
  52                     int i = 0;;
  53                     for(;i < inheritedVariableBindings.length;++i)
  54                         newVariableBindings[i] = inheritedVariableBindings[i];
  55                     newVariableBindings[i++] = param0;
  56                     newVariableBindings[i] = param1;
  57                     return body.execute(newVariableBindings);
  58                 }
  59
  60                 @Override
  61                 public String toString() {
  62                         return ILambda.this.toString(inheritedVariableBindings);
  63                 }
  64             };
  65         case 3:
  66             return new FunctionImpl3() {
  67                 @Override
  68                 public Object apply(Object param0, Object param1, Object param2) {
  69                     Object[] newVariableBindings = new Object[variableBindingsLength];
  70                     int i = 0;;
  71                     for(;i < inheritedVariableBindings.length;++i)
  72                         newVariableBindings[i] = inheritedVariableBindings[i];
  73                     newVariableBindings[i++] = param0;
  74                     newVariableBindings[i++] = param1;
  75                     newVariableBindings[i] = param2;
  76                     return body.execute(newVariableBindings);
  77                 }
  78
  79                 @Override
  80                 public String toString() {
  81                         return ILambda.this.toString(inheritedVariableBindings);
  82                 }
  83             };
  84         case 4:
  85             return new FunctionImpl4() {
  86                 @Override
  87                 public Object apply(Object param0, Object param1, Object param2, Object param3) {
  88                     Object[] newVariableBindings = new Object[variableBindingsLength];
  89                     int i = 0;;
  90                     for(;i < inheritedVariableBindings.length;++i)
  91                         newVariableBindings[i] = inheritedVariableBindings[i];
  92                     newVariableBindings[i++] = param0;
  93                     newVariableBindings[i++] = param1;
  94                     newVariableBindings[i++] = param2;
  95                     newVariableBindings[i] = param3;
  96                     return body.execute(newVariableBindings);
  97                 }
  98
  99                 @Override
 100                 public String toString() {
 101                         return ILambda.this.toString(inheritedVariableBindings);
 102                 }
 103             };
 104         default:
 105             return new FunctionImplN(arity) {
 106                 @Override
 107                 public Object doApply(Object... ps) {
 108                     Object[] newVariableBindings = new Object[variableBindingsLength];
 109                     int i = 0;;
 110                     for(;i < inheritedVariableBindings.length;++i)
 111                         newVariableBindings[i] = inheritedVariableBindings[i];
 112                     for(Object p : ps)
 113                         newVariableBindings[i++] = p;
 114                     return body.execute(newVariableBindings);
 115                 }
 116
 117                 @Override
 118                 public String toString() {
 119                         return ILambda.this.toString(inheritedVariableBindings);
 120                 }
 121             };
 122         }
 123     }
 124
 125     @Override
 126     public String toString() {
 127         StringBuilder b = new StringBuilder();
 128         b.append("(\\");
 129         for(int i=0;i<inheritedVariableIds.length;++i)
 130             b.append('v').append(i)
 131             .append("(v").append(inheritedVariableIds[i]).append(") ");
 132         for(int i=0;i<arity;++i)
 133             b.append('v').append(i+inheritedVariableIds.length).append(' ');
 134         b.append("-> ");
 135         b.append(body);
 136         b.append(')');
 137         return b.toString();
 138     }
 139
 140     public String toString(Object[] variableBindings) {
 141         StringBuilder sb = new StringBuilder();
 142         appendVariableBindings(sb, variableBindings);
 143         sb.append(this.toString());
 144         return sb.toString();
 145     }
 146
 147     private static void appendVariableBindings(StringBuilder sb, Object[] variableBindings) {
 148         if (variableBindings.length > 0) {
 149                 sb.append("(let {");
 150                 for(int i = 0; i < variableBindings.length; i++) {
 151                         if (i > 0) sb.append("; ");
 152                         sb.append("v").append(i).append("=").append(variableBindings[i].toString());
 153                 }
 154                 sb.append("} in ");
 155         }
 156     }
 157 }