public override object Visit(AstNode node) {
var result = node.Accept(this);
VisitChildren(node);
return result;
}
private EvaluationResult Evaluate(AstNode node) {
return (EvaluationResult)this.Visit(node);
}
public IEnumerable<ErrorAstNode> Collect(AstNode root) {
this.Visit(root);
return _errors;
}
public virtual object VisitChildren(AstNode node) {
return node.Children.Aggregate<AstNode, object>(null, (prev, child) => Visit(child));
}
public virtual object Visit(AstNode node) {
return node.Accept(this);
}
private void CheckExpression(AstNode astNode, int indent, object[] objects, ref int index) {
var exprName = (string)objects[index++];
Type type = null;
switch (exprName) {
case "const":
type = typeof(ConstantAstNode);
break;
case "binop":
type = typeof(BinaryAstNode);
break;
case "unop":
type = typeof(UnaryAstNode);
break;
case "call":
type = typeof(MethodCallAstNode);
break;
case "error":
type = typeof(ErrorAstNode);
break;
default:
throw new InvalidOperationException(string.Format("Test error: unrecognized expression type abbreviation '{0}'", exprName));
}
Trace.WriteLine(string.Format("{0}: {1}{2} (Current: {3})", indent, new string(' ', indent * 2), type.Name, astNode));
Assert.That(astNode.GetType(), Is.EqualTo(type));
if (exprName == "const") {
Assert.That((astNode as ConstantAstNode).Value, Is.EqualTo(objects[index++]));
}
else if (exprName == "binop") {
Assert.That((astNode as BinaryAstNode).Operator.Kind, Is.EqualTo(objects[index++]));
}
else if (exprName == "unop") {
Assert.That((astNode as UnaryAstNode).Operator.Kind, Is.EqualTo(objects[index++]));
}
else if (exprName == "call") {
Assert.That((astNode as MethodCallAstNode).Token.Kind, Is.EqualTo(objects[index++]));
Assert.That((astNode as MethodCallAstNode).Token.Value, Is.EqualTo(objects[index++]));
}
foreach (var child in astNode.Children) {
CheckExpression(child, indent + 1, objects, ref index);
}
}
public UnaryAstNode(Token token, AstNode operand) {
_operand = operand;
_token = token;
}
public BinaryAstNode(AstNode left, Token token, AstNode right) {
_left = left;
_token = token;
_right = right;
}