es1.setType(DataTypeManager.DefaultDataClasses.STRING);
List elements = new ArrayList();
elements.add(es1);
Function func = new Function("lookup", new Expression[] { new Constant("pm1.g1"), new Constant("e2"), new Constant("e1"), es1 }); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$ //$NON-NLS-4$
FunctionDescriptor desc = FakeMetadataFactory.SFM.getSystemFunctionLibrary().findFunction("lookup", new Class[] { String.class, String.class, String.class, String.class } ); //$NON-NLS-1$
func.setFunctionDescriptor(desc);
func.setType(DataTypeManager.DefaultDataClasses.STRING);
ExpressionSymbol expr = new ExpressionSymbol("expr", func); //$NON-NLS-1$
List projectElements = new ArrayList();