public virtual TreeNode OnWhile(TreeNode [] args)
{
if(args == null || args.Length < 1 || args.Length > 2) {
throw new ArgumentException("while accepts a condition and an expression or just an expression");
}
while(true) {
if(args.Length == 2) {
TreeNode result = Evaluate(args[0]);
if(!(result is BooleanLiteral)) {
throw new ArgumentException("condition is not boolean");
}
if(!(result as BooleanLiteral).Value) {
break;
}
}
try {
Evaluate(args[args.Length - 1]);
} catch(Exception e) {
if(BreakHandler(e)) {
break;
}
}
}
return new VoidLiteral();
}
public virtual TreeNode OnDefine(TreeNode [] args)
{
if(args.Length < 2 || args.Length > 3) {
throw new ArgumentException("define must have two or three arguments");
}
if(!(args[0] is FunctionNode)) {
throw new ArgumentException("first define argument must be a variable");
}
FunctionNode function = new FunctionNode((args[0] as FunctionNode).Function, args[args.Length - 1]);
if(args.Length == 3 && args[1].HasChildren) {
foreach(TreeNode function_arg in args[1].Children) {
if(!(function_arg is FunctionNode)) {
throw new ArgumentException("define function arguments must be variable tokens");
}
function.RegisterFunction((function_arg as FunctionNode).Function, new VoidLiteral());
}
}
TreeNode parent = args[0].Parent;
parent = parent.Parent ?? parent;
parent.RegisterFunction(function.Function, function);
return new VoidLiteral();
}
public static TreeNode Compare(EvaluatorBase evaluator, TreeNode a, TreeNode b)
{
TreeNode arg_a = evaluator.Evaluate(a);
TreeNode arg_b = evaluator.Evaluate(b);
if(arg_a.GetType() != arg_b.GetType()) {
throw new ArgumentException("arguments must be of the same type to compare");
}
int result = 0;
if(arg_a is IntLiteral) {
result = (arg_a as IntLiteral).Value.CompareTo(
(arg_b as IntLiteral).Value);
} else if(arg_a is DoubleLiteral) {
result = (arg_a as DoubleLiteral).Value.CompareTo(
(arg_b as DoubleLiteral).Value);
} else if(arg_a is StringLiteral) {
result = (arg_a as StringLiteral).Value.CompareTo(
(arg_b as StringLiteral).Value);
} else if(arg_a is BooleanLiteral) {
result = (arg_a as BooleanLiteral).Value.CompareTo(
(arg_b as BooleanLiteral).Value);
} else {
throw new ArgumentException("invalid type for comparison");
}
return new IntLiteral(result);
}
public TreeNode Flatten()
{
TreeNode result_node = new TreeNode();
Flatten(result_node, this);
return result_node.ChildCount == 1 ? result_node.Children[0] : result_node;
}
private void CheckArgumentCount(TreeNode [] args, int expected_min, int expected_max)
{
if(args.Length < expected_min || args.Length > expected_max) {
throw new ArgumentException("expects " + expected_min + " <= args <= "
+ expected_max + " arguments");
}
}
private TreeNode OnAndOr(TreeNode [] args, bool and)
{
if(args.Length < 2) {
throw new ArgumentException("must have two or more boolean arguments");
}
bool result = false;
for(int i = 0; i < args.Length; i++) {
TreeNode node = Evaluate(args[i]);
if(!(node is BooleanLiteral)) {
throw new ArgumentException("arguments must be boolean");
}
BooleanLiteral arg = (BooleanLiteral)node;
if(i == 0) {
result = arg.Value;
continue;
}
if(and) {
result &= arg.Value;
} else {
result |= arg.Value;
}
}
return new BooleanLiteral(result);
}
public virtual TreeNode OnCompareTo(TreeNode [] args)
{
if(args.Length != 2) {
throw new ArgumentException("must have two arguments");
}
return Compare(Evaluator, args[0], args[1]);
}
public virtual TreeNode OnDump(TreeNode [] args)
{
foreach(TreeNode arg in args) {
Evaluate(arg).Dump();
}
return new VoidLiteral();
}
private int GetArgumentInteger(TreeNode [] args, int index)
{
TreeNode node = Evaluate(args[index]);
if(!(node is IntLiteral)) {
throw new ArgumentException("argument " + index + " must be an integer");
}
return (node as IntLiteral).Value;
}
private string GetArgumentString(TreeNode [] args, int index)
{
TreeNode node = Evaluate(args[index]);
if(!(node is StringLiteral)) {
throw new ArgumentException("argument " + index + " must be a string");
}
return (node as StringLiteral).Value;
}
public virtual TreeNode OnPrintType(TreeNode [] args)
{
if(args.Length != 1) {
throw new ArgumentException("print-type must have only one argument");
}
Console.WriteLine(Evaluate(args[0]).GetType());
return new VoidLiteral();
}
public virtual TreeNode OnPerformArithmetic(TreeNode [] args, ArithmeticOperation operation)
{
double result = 0.0;
bool as_int = true;
for(int i = 0; i < args.Length; i++) {
TreeNode arg = Evaluate(args[i]);
if(arg is IntLiteral || arg is DoubleLiteral) {
double arg_value;
if(arg is DoubleLiteral) {
as_int = false;
arg_value = (arg as DoubleLiteral).Value;
} else {
arg_value = (int)(arg as IntLiteral).Value;
}
if(i == 0) {
result = arg_value;
continue;
}
switch(operation) {
case ArithmeticOperation.Add:
result += arg_value;
break;
case ArithmeticOperation.Subtract:
result -= arg_value;
break;
case ArithmeticOperation.Multiply:
result *= arg_value;
break;
case ArithmeticOperation.Divide:
result /= arg_value;
break;
case ArithmeticOperation.Modulo:
if(!(arg is IntLiteral)) {
throw new ArgumentException("Modulo requires int arguments");
}
result %= (int)arg_value;
break;
}
} else {
throw new ArgumentException("arguments must be double or int");
}
}
return as_int ?
((TreeNode)new IntLiteral((int)result)) :
((TreeNode)new DoubleLiteral(result));
}
public static TreeNode ConcatenateStrings(EvaluatorBase evaluator, TreeNode [] args)
{
StringBuilder result = new StringBuilder();
foreach(TreeNode arg in args) {
TreeNode eval_arg = evaluator.Evaluate(arg);
if(!(eval_arg is VoidLiteral)) {
result.Append(eval_arg);
}
}
return new StringLiteral(result.ToString());
}
public virtual TreeNode OnNot(TreeNode [] args)
{
if(args.Length != 1) {
throw new ArgumentException("not must have only one argument");
}
TreeNode arg = Evaluate(args[0]);
if(!(arg is BooleanLiteral)) {
throw new ArgumentException("can only not a boolean");
}
return new BooleanLiteral(!(arg as BooleanLiteral).Value);
}
private void Flatten(TreeNode result_node, TreeNode node)
{
if(node == null) {
return;
}
if(!node.HasChildren && !(node is VoidLiteral)) {
result_node.AddChild(node);
return;
}
foreach(TreeNode child_node in node.Children) {
Flatten(result_node, child_node);
}
}
public virtual TreeNode OnItemAt(TreeNode [] args)
{
TreeNode list = Evaluate(args[0]);
CheckList(list);
TreeNode node = Evaluate(args[1]);
int index = 0;
if(!(node is IntLiteral)) {
throw new ArgumentException("argument must be an index");
}
index = (node as IntLiteral).Value;
return Evaluate(list.Children[index]);
}
public virtual TreeNode OnCastString(TreeNode [] args)
{
if(args.Length != 1) {
throw new ArgumentException("cast must have only one argument");
}
TreeNode arg = Evaluate(args[0]);
if(arg is DoubleLiteral) {
return new StringLiteral(Convert.ToString((arg as DoubleLiteral).Value));
} else if(arg is IntLiteral) {
return new StringLiteral(Convert.ToString((arg as IntLiteral).Value));
} else if(arg is StringLiteral) {
return arg;
}
throw new ArgumentException("can only cast double, int, or string literals");
}
public virtual TreeNode OnIf(TreeNode [] args)
{
if(args == null || args.Length < 2 || args.Length > 3) {
throw new ArgumentException("if accepts 2 or 3 arguments");
}
TreeNode arg = Evaluate(args[0]);
if(!(arg is BooleanLiteral)) {
throw new ArgumentException("first if argument must be boolean");
}
BooleanLiteral conditional = (BooleanLiteral)arg;
if(conditional.Value) {
return Evaluate(args[1]);
} else if(args.Length == 3) {
return Evaluate(args[2]);
}
return new VoidLiteral();
}
public TreeNode Evaluate(EvaluatorBase evaluator, TreeNode [] args)
{
if(args != null && args.Length != FunctionCount && RequiresArguments) {
throw new ArgumentException("Function " + function + " takes "
+ FunctionCount + " arguments, not " + args.Length);
}
if(args != null && RequiresArguments) {
int i = 0;
string [] names = new string[args.Length];
foreach(KeyValuePair<string, FunctionNode> var in Functions) {
names[i++] = var.Key;
}
for(i = 0; i < args.Length; i++) {
(body as TreeNode).RegisterFunction(names[i], evaluator.Evaluate(args[i]));
}
}
return evaluator.Evaluate(ResolveBody(evaluator));
}
public static TreeNode VariableSet(EvaluatorBase evaluator, TreeNode [] args, bool update)
{
if(args.Length != 2) {
throw new ArgumentException("must have two arguments");
}
if(!(args[0] is FunctionNode)) {
throw new ArgumentException("first argument must be a variable");
}
FunctionNode variable_node = evaluator.ResolveFunction(args[0] as FunctionNode);
if(variable_node != null) {
variable_node.Body = evaluator.Evaluate(args[1]);
} else {
TreeNode parent = args[0].Parent;
parent = parent.Parent ?? parent;
parent.RegisterFunction((args[0] as FunctionNode).Function, evaluator.Evaluate(args[1]));
}
return new VoidLiteral();
}
public TreeNode Parse(StreamReader reader)
{
this.reader = reader;
current_token = new StringBuilder();
root_node = new TreeNode();
current_parent = root_node;
scope = 0;
line = 1;
column = 0;
try {
Tokenize();
if(scope != 0) {
throw new ApplicationException("Scope does pop back to zero");
}
} catch(Exception e) {
throw new ParserException(current_token.ToString(), line, column, e);
}
return root_node;
}
public virtual TreeNode OnIsList(TreeNode [] args)
{
return new BooleanLiteral(IsList(args[0]));
}
public void CheckList(TreeNode node)
{
if(!IsList(node)) {
throw new ArgumentException("argument must be a list");
}
}
// FIXME: Why is this here? --Aaron
//
// private TreeNode EvaluateList(TreeNode node)
// {
// TreeNode list = new TreeNode();
//
// foreach(TreeNode child in node.Children) {
// list.AddChild(Evaluate(child));
// }
//
// return list;
// }
private bool IsList(TreeNode node)
{
return !(node is LiteralNodeBase) && !(node is FunctionNode);
}
public virtual TreeNode OnForeach(TreeNode [] args)
{
TreeNode list = Evaluate(args[1]);
CheckList(list);
FunctionNode item_variable = (FunctionNode)args[0];
TreeNode function = args[2];
TreeNode self = args[0].Parent.Children[0];
self.Parent.RegisterFunction(item_variable.Function, item_variable);
foreach(TreeNode child in list.Children) {
item_variable.Body = child;
try {
if(function is FunctionNode) {
FunctionNode function_impl = Evaluator.ResolveFunction(function as FunctionNode);
function_impl.Evaluate(Evaluator, new TreeNode [] { child });
} else {
Evaluate(function);
}
} catch(Exception e) {
if(ControlFunctionSet.BreakHandler(e)) {
break;
}
}
}
return new VoidLiteral();
}
public virtual TreeNode OnPrepend(TreeNode [] args)
{
TreeNode list = Evaluate(args[0]);
CheckList(list);
list.Children.Insert(0, Evaluate(args[1]));
return list;
}
public virtual TreeNode OnAppend(TreeNode [] args)
{
TreeNode list = Evaluate(args[0]);
CheckList(list);
list.Children.Add(Evaluate(args[1]));
return list;
}
public virtual TreeNode OnRemove(TreeNode [] args)
{
TreeNode list = Evaluate(args[0]);
CheckList(list);
TreeNode node = Evaluate(args[1]);
foreach(TreeNode compare_node in list.Children) {
if(((IntLiteral)CompareFunctionSet.Compare(Evaluator, node, compare_node)).Value == 0) {
list.Children.Remove(compare_node);
break;
}
}
return list;
}
public TreeNode Evaluate(TreeNode node)
{
return evaluator.Evaluate(node);
}
public Evaluator(TreeNode expression) : base(expression)
{
RegisterFunctions();
}