Added primitives for selecting/setting field on nodes; settles #1078

usethesource · May 28, 2017 · f15878e · f15878e
1 parent febbef6
commit f15878e
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diff --git a/src/org/rascalmpl/library/experiments/Compiler/RVM/Interpreter/RascalPrimitive.java b/src/org/rascalmpl/library/experiments/Compiler/RVM/Interpreter/RascalPrimitive.java
@@ -6197,6 +6197,31 @@ public Object execute2(final Object arg_2, final Object arg_1, final Frame curre
 			}
 		}
 	},
+
+	/**
+     * Retrieve value of named field of node
+     * 
+     * [ ..., INode nd, IString fieldName ] => [ ..., IValue value of field fieldName ]
+     */
+	node_field_access {
+	    @Override
+	    public Object execute2(final Object arg_2, final Object arg_1, final Frame currentFrame, final RascalExecutionContext rex) {
+	        INode nd = (INode) arg_2;
+	        IString field = (IString) arg_1;
+	        String fieldName = field.getValue();
+	        // A default field that was set?
+
+	        IValue v = null;
+	        if(nd.mayHaveKeywordParameters()){
+	            v = nd.asWithKeywordParameters().getParameter(fieldName);
+	        }
+	        if(v != null){
+	            return v;
+	        }
+
+	        return rex.getFrameObserver().exception(currentFrame,  RascalRuntimeException.noSuchField(fieldName, currentFrame));
+	    }
+	},
 
 	/**
 	 * Retrieve value of named field of constructor
@@ -7069,6 +7094,30 @@ public int executeN(Object[] stack, int sp, int arity, Frame currentFrame, Rasca
 			return sp - arity + 1;
 		}
 	},
+
+	 /**
+     * Set named field of node value
+     * 
+     * [ ..., INode nd, IString fieldName, IValue repl... ] => [ ...,  new INode with named field set to repl ]
+     */
+    node_field_update {
+        @Override
+        public int executeN(Object[] stack, int sp, int arity, Frame currentFrame, RascalExecutionContext rex) {
+            assert arity == 3;
+            INode nd = (INode) stack[sp - 3];
+            IString field = ((IString) stack[sp - 2]);
+            String fieldName = field.getValue();
+            IValue repl = (IValue) stack[sp - 1];
+            if(nd.mayHaveKeywordParameters()){
+                stack[sp - 3] = nd.asWithKeywordParameters().setParameter(fieldName, repl);
+                return sp - 2;
+            } else {
+                rex.getFrameObserver().exception(currentFrame, 
+                    RascalRuntimeException.noSuchField(fieldName, currentFrame));
+            }
+            return sp - 2;
+        }
+	},
 
 	/**
 	 * Set named field of constructor value

diff --git a/src/org/rascalmpl/library/experiments/Compiler/Rascal2muRascal/RascalExpression.rsc b/src/org/rascalmpl/library/experiments/Compiler/Rascal2muRascal/RascalExpression.rsc
@@ -1761,7 +1761,7 @@ MuExp translate (e:(Expression) `<Expression expression> [ <Name key> = <Express
     } else if(isLocType(tp)){
      	return muCallPrim3("loc_field_update", [ translate(expression), muCon(unescape("<key>")), translate(replacement) ], e@\loc);
     } else if(isNodeType(tp)){
-        throw "Field update on node: <e>";
+        return muCallPrim3("node_field_update", [ translate(expression), muCon(unescape("<key>")), translate(replacement) ], e@\loc);
     }
     if(tupleHasFieldNames(tp)){
     	  fieldNames = getTupleFieldNames(tp);