// TODO: The method apply() should be defined in class Node
// to report an error. It should be overridden only in classes
// BuiltIn and Closure.
//public /* override */ Node apply (Node args)
//{
// return new StringLit("Error: BuiltIn.apply not yet implemented");
//}
public override Node apply(Node args)
{
int num = Util.expLength(args);
bool flag = num > 2;
if (flag)
{
Console.Error.WriteLine("Error: wrong number of arguments");
}
bool flag2 = num == 0; // length 0 arguments
Node result;
if (flag2)
{
result = this.apply0();
}
else //1 or 2 argument lengths
{
bool flag3 = num == 1; // length 1 arguments
if (flag3)
{
result = this.apply1(args.getCar());
}
else
{
result = this.apply2(args.getCar(), args.getCdr().getCar());
}
}
return result;
}
public override Node eval(Node t, Environment env)
{
Node clauseList = t.getCdr();
Node clause = clauseList.getCar();
while(clause != Nil.getInstance())
{
Node predicate = clause.getCar().eval(env);
if(predicate == BoolLit.getInstance(true) || predicate.getName() == "else")
{
Node expressionList = clause.getCdr();
//evaluate all expressions and return the result of the last evaluation
Node lastEval = expressionList.getCar().eval(env);
//If there are more expressions to evaluate
while(expressionList.getCdr() != Nil.getInstance())
{
expressionList = expressionList.getCdr();
lastEval = expressionList.getCar().eval(env);
}
return lastEval;
}
clauseList = clauseList.getCdr();
clause = clauseList.getCar();
}
//Does not yet handle else's
return Nil.getInstance();
}
public override void print(Node t, int n, bool p)
{
for (int i = Console.CursorLeft; i < n; i++)
Console.Write(" ");
if (!p)
Console.Write("(");
//Print "lambda"
t.getCar().print(n);
Console.Write(" ");
Node second = t.getCdr().getCar();
if (second.isPair())
{
second.print(n, false);
}
Console.WriteLine();
Node term = t.getCdr().getCdr();
while(!term.isNull())
{
term.getCar().print(n + 4);
term = term.getCdr();
Console.WriteLine();
}
Nil.getNil().print(n,true);
}
public override void print(Node t, int n, bool p)
{
if (!p)
{
var spaces = "";
if (n >= 0) spaces = new string(' ', n);
Console.Write(spaces + "(if ");
if (t.getCdr().getCar().isPair())
{
if((t.getCdr().getCar() as Cons).form is If ||
(t.getCdr().getCar() as Cons).form is Lambda ||
(t.getCdr().getCar() as Cons).form is Define)
t.getCdr().getCar().print(n+4, true);
else
{
t.getCdr().getCar().print(0, false);
}
}
else
t.getCdr().getCar().print(0, false);
t = t.getCdr().getCdr();
do
{
Console.WriteLine("");
t.getCar().print(n + 4, false);
t = t.getCdr();
} while (t.getCdr() != null);
Console.WriteLine("");
t.print(n, true);
}
else
{
var spaces = "";
if (n >= 0) spaces = new string(' ', n);
Console.Write("(if ");
if (t.getCdr().getCar().isPair())
{
if ((t.getCdr().getCar() as Cons).form is If ||
(t.getCdr().getCar() as Cons).form is Lambda ||
(t.getCdr().getCar() as Cons).form is Define)
t.getCdr().getCar().print(n+4, true);
else
{
t.getCdr().getCar().print(0, false);
}
}
t.getCdr().getCar().print(0, false);
t = t.getCdr().getCdr();
do
{
Console.WriteLine("");
t.getCar().print(n + 4, false);
t = t.getCdr();
} while (t.getCdr() != null);
Console.WriteLine("");
t.print(n, true);
}
}
public override void print(Node t, int n, bool p)
{
for (int i = Console.CursorLeft; i < n; i++)
Console.Write(" ");
if (!p)
{
Console.Write("(");
}
//print "let"
t.getCar().print(n);
Console.WriteLine();
Node rest = t.getCdr();
if (rest.isPair())
{
rest.getCar().print(n + 4, false);
Console.WriteLine();
while ((rest = rest.getCdr()) != Nil.getNil())
{
rest.getCar().print(n + 4, false);
Console.WriteLine();
}
Console.Write(")");
}
else t.getCdr().print(n, true);
}
public Node evalLetBody(Node t, Environment env)
{
if(t == Nil.getInstance()) //This isn't correct. What do?
{
Node l = new Cons(new Nil(), new Nil()); //tree with pair of ()
return l;
}
else
{
Node restBody = t.getCdr();
Node variable = t.getCar().getCar();
Node value = t.getCar().getCdr().getCar();
if(variable.isSymbol()) //was value earlier, should be variable?
{
env.define(variable,value.eval(env));
return evalLetBody(restBody, env);
}
else if(!variable.isPair()) //if it is a cons node. ???
{
Console.Write("Error in Let->evalLetBody, variable is not valid");
return new Nil();
}
else if(variable.isNull())
{
return new Nil();
}
else
{
return variable.eval(env);
}
}
}
public override void print(Node t, int n, bool p)
{
Console.Write("".PadLeft(n));
if ( p != true)
{
Console.Write("(");
}
if(t.getCar().isPair())
{
t.getCar().print(0);
}
else
{
t.getCar().print(0, true);
}
Console.Write(" ");
if(t.getCdr() is Nil)
{
Console.WriteLine(")");
}
else
{
t.getCdr().print(0, true);
}
// Console.WriteLine();
}
public override void print(Node t, int n, bool p)
{
// TODO: Implement this function.
Console.Write("".PadLeft(n));
Console.Write("(define ");
Node name = t.getCdr().getCar();
name.print(n);
Console.Write(" ");
Node definition = t.getCdr().getCdr().getCar();
if (definition.isNull())
{
Console.Error.Write("Syntax error with DEFINE-definition");
}
else if (definition.isPair())
{
Console.WriteLine();
// Console.Write("".PadLeft(n+4));
definition.print(n+4);
}
else
{
definition.print(n);
}
// made n to 0
// Console.WriteLine();
Console.WriteLine("".PadLeft(n) + ")");
}
// Key Deletion
public bool Delete(double key)
{
bool value = KeyDeletion(null, root, key);
if (root.key.Count == 0 && root.children[0] != null)
root = root.children[0];
return value;
}
/* A O(n) iterative program for construction of BST from preorder traversal */
public Node ConstuctTreeFromPreOrder(int[] preOrder)
{
Node root = new Node();
root.data = preOrder[0];
Stack<Node> _stack = new Stack<Node>();
Node temp;
for (int i = 1; i < preOrder.Length; i++)
{
temp = null;
while (_stack.Count > 0 && preOrder[i] > _stack.Peek().data)
{
temp = _stack.Pop();
}
if (temp != null)
{
temp.right.data = preOrder[i];
_stack.Push(temp.right);
}
else
{
temp.left.data = preOrder[i];
_stack.Push(temp.left);
}
}
return root;
}
static Tree<int> ParseTree()
{
var nodes = new Dictionary<int, Node<int>>();
Console.Write("Number of nodes:");
int n = int.Parse(Console.ReadLine());
Console.WriteLine("Start typing the node pairs separated by a single space");
for (int i = 0; i < n-1; i++)
{
var pair = Console.ReadLine().Split();
int first = int.Parse(pair[0]);
int second = int.Parse(pair[1]);
if (!nodes.ContainsKey(first))
{
Node<int> parent = new Node<int>(first);
nodes.Add(first, parent);
}
if (!nodes.ContainsKey(second))
{
Node<int> newNode = new Node<int>(second);
newNode.HasParent = true;
nodes.Add(second,newNode);
nodes[first].Children.Add(newNode);
}
nodes[first].Children.Add(nodes[second]);
nodes[second].HasParent=true;
}
var root = nodes.First(x => x.Value.HasParent == false);
var tree = new Tree<int>(root.Value);
return tree;
}
// TODO: The method apply() should be defined in class Node
// to report an error. It should be overridden only in classes
// BuiltIn and Closure.
public override Node apply (Node args)
{
Node param = fun.getCdr().getCar();
int numArgs = Util.expLength(args);
int numParam = Util.expLength(param);
if (numArgs != numParam)
{
Console.Error.WriteLine("Error: wrong number of arguments");
}
Environment env1 = new Environment(env);
while (param.isPair() && args.isPair())
{
Node id = param.getCar();
Node val = args.getCar();
env1.define(id, val);
param = param.getCdr();
args = args.getCdr();
}
while (param.isPair())
{
Node id = param.getCar();
Node val = Nil.getInstance();
env1.define(id, val);
param = param.getCdr();
}
Node exp1 = fun.getCdr().getCdr();
return Begin.evalBody(exp1, env1);
}
public override void print(Node t, int n, bool p)
{
// TODO: Implement this function.
// Console.Write("".PadLeft(n));
if (!p)
{
Console.Write("".PadLeft(n) + '(');
}
t.getCar().print(0, !p);
// if(!t.getCdr().isNull())
// {
// Console.Write(" ");
// }
if(t.getCdr().isNull())
{
t.getCdr().print(0, true);
// Console.WriteLine();
}
else {
Console.Write(" ");
t.getCdr().print(n, true);
}
// if(t.getCdr().isNull())
// {
// Console.WriteLine();
// }
}
public override Node eval(Node t, Environment env)
{
if (t.getCdr() == Nil.getInstance())
{
Console.Error.WriteLine("Error: invalid argument");
throw new InvalidOperationException();
}
if (t.getCdr().getCar().eval(env) != BoolLit.getInstance(false))
{
if (t.getCdr().getCdr() == Nil.getInstance())
{
Console.Error.WriteLine("Error: invalid argument");
throw new InvalidOperationException();
}
return t.getCdr().getCdr().getCar().eval(env);
}
if (t.getCdr().getCdr() == Nil.getInstance())
{
Console.Error.WriteLine("Error: invalid argument");
throw new InvalidOperationException();
}
if (t.getCdr().getCdr().getCdr() == Nil.getInstance())
{
return Nil.getInstance();
}
return t.getCdr().getCdr().getCdr().getCar().eval(env);
}
public override Node eval(Node exp, Environment env)
{
int length = Util.expLength(exp);
if (length < 3)
{
Console.Error.WriteLine("Error: invalid expression");
return Nil.getInstance();
}
Node second = exp.getCdr().getCar();
while (second.isPair())
{
if (Util.expLength(second.getCar()) != 2)
{
Console.Error.WriteLine("Error: invalid expression");
return Nil.getInstance();
}
second = second.getCdr();
}
second = exp.getCdr().getCar();
Environment env1 = new Environment(env);
while (second.isPair())
{
Node id = second.getCar().getCar();
Node val = second.getCar().getCdr().getCar();
env1.define(id, val);
second = second.getCdr();
}
Node exp1 = exp.getCdr().getCdr();
return Begin.evalBody(exp1, env1);
}
public override Node eval(Node t, Environment e)
{
if(t.getCdr() is Closure)
return e.lookup(t.getCar()).apply(t.getCdr());
else
{
Node args = t.getCdr();
Node param;
if (args.getCar().isSymbol())
param = new Cons(e.lookup((Node)args.GetCar()), Nil.getInstance());
else
param = new Cons((Node)args.GetCar(), Nil.getInstance());
Node currentNode = param;
args = args.getCdr();
while (args != Nil.getInstance())
{
if (args.getCar().isSymbol())
currentNode.setCdr(new Cons(e.lookup(args.getCar()), Nil.getInstance()));
else
currentNode.setCdr(new Cons(args.getCar(), Nil.getInstance()));
currentNode = currentNode.getCdr();
args = args.getCdr();
}
return e.lookup(t.getCar()).apply(param);
}
}
public override void print(Node t, int n, bool p)
{
// print leading spaces and '
if (n < 0)
{
n = -(n + 1);
}
Console.Write(new string(' ', n) + "'");
// if quote a list
if (t.getCdr().getCar().isPair())
{
// this while is to print following quote as ' to get the sample output
while (t.getCdr().getCar().getCar().isSymbol()
&& ((Ident) t.getCdr().getCar().getCar()).getName().Equals("quote"))
{
Console.Write("'");
t = t.getCdr().getCar();
}
// using the Regular form to print quoted list
Special v = new Regular();
v.print(t.getCdr().getCar(), 0, false);
// if the caller asks for change line
if (n > 0)
{
Console.WriteLine();
}
}
// if quote a single element
else
{
t.getCdr().getCar().print(0);
}
}
//Function for pairing up arguments with corresponding symbols
private static void pairup(Node parms, Node args, Environment env)
{
//if null return nothing
if (parms.isNull() && args.isNull())
{
return;
}
//check the symbol type
if (parms.isSymbol())
{
env.define(parms, args);
}
//depending on the parameter, check the # of required valid arguments
else if (parms.isNull() || args.isNull())
{
Console.get_Error().WriteLine("Error: wrong number of arguments");
}
//look for values in different env w/ closure pointer? idk how to explain this
else if (parms.isPair() && args.isPair())
{
env.define(parms.getCar(), args.getCar());
Closure.pairup(parms.getCdr(), args.getCdr(), env);
}
else
{
Console.get_Error().WriteLine("Error: invalid expression");
}
}
public override Node eval(Node exp, Environment env)
{
int length = Util.expLength(exp);
if (length < 3)
{
Console.Error.WriteLine("Error: invalid expression");
return Nil.getInstance();
}
Node second = exp.getCdr().getCar();
Node name, value;
if (length == 3 && second.isSymbol())
{
name = second;
value = exp.getCdr().getCdr().getCar().eval(env);
env.define(name, value);
return null;
}
if (!second.isPair())
{
Console.Error.WriteLine("Error: invalid expression");
return Nil.getInstance();
}
name = second.getCar();
Node lambda = exp.getCdr();
lambda.setCar(second.getCdr());
lambda = new Cons(new Ident("lambda"), lambda);
value = lambda.eval(env);
env.define(name, value);
return null;
}
public override void print(Node t, int n, bool p)
{
// TODO: Implement this function.
Console.Write("".PadLeft(n));
Console.WriteLine("(let");
Node bindings = t.getCdr().getCar();
if (bindings.isPair())
{
bindings.print(0,false);
}
else
{
Console.Error.WriteLine("Syntax error for LET-BINDINGS");
}
Console.Write("".PadLeft(n));
Node body = t.getCdr().getCdr();
if (body.isPair())
{
body.print(n+4, true);
}
else
{
Console.Error.WriteLine("Syntax error for LET-BODY");
}
Console.Write("".PadLeft(n)+ ")");
}
public override Node eval(Node t, Environment e)
{
while (t.getCdr() != Nil.getInstance())
{
t = t.getCdr();
if (t.getCar().GetType() != typeof(Cons))
{
Console.Error.WriteLine("Error: invalid argument");
throw new InvalidOperationException();
}
if (t.getCar().getCar().eval(e) == BoolLit.getInstance(true))
{
t = t.getCar();
while(t.getCdr() != Nil.getInstance())
{
t = t.getCdr();
if (t.getCdr() == Nil.getInstance()) break;
t.getCar().eval(e);
}
return (Node)t.getCar().eval(e);
}
else if (t.getCar().getCar().eval(e) != BoolLit.getInstance(false))
{
Console.Error.WriteLine("Error: invalid argument");
throw new InvalidOperationException();
}
}
return Nil.getInstance();
}
public void assign(Node id, Node val)
{
// TODO: implement this function
// create name
// if (search for name in either frame or environment)
// name = newvalue
}
// REMEMBER: If not explictly false, then true.
public Node eval(Node t, Environment e)
{
Node cond = t.getCdr().getCar(); // condition -> cadr(exp)
if (cond == null)
{
Console.Error.WriteLine("Error: Null in Condition");
}
Node ifTrue = t.getCdr().getCdr().getCar(); // true -> caddr(exp)
if (ifTrue == null)
{
Console.Error.WriteLine("Error: Null in True/If");
}
Node ifFalse = t.getCdr().getCdr().getCdr().getCar(); // false -> cadddr(exp)
if (ifFalse == null)
{
Console.Error.WriteLine("Error: Null in False/Else");
}
bool checkTrueResult = checkTrue(t, e);
if (checkTrueResult == true)
{
return ifTrue.eval(ifTrue, e);
}
else
{
return ifFalse.eval(ifFalse, e);
}
}
public override void print(Node t, int n, bool p)
{
Console.Write("".PadLeft(n));
Console.Write("(lambda");
Node Num2Node = t.getCdr().getCar();
if (Num2Node.isPair())
{
Num2Node.print(0,false);
}
else
{
Console.Error.Write("Syntax Error with Lambda (Num2Node)");
}
Console.Write("".PadLeft(n));
Node Num3Node = t.getCdr().getCdr().getCar();
if( Num3Node.isPair())
{
Num3Node.print(n+4, false);
}
else
{
Console.Error.Write("Syntax Error with Lambda (Num3Node)");
}
Console.Write("".PadLeft(n));
}
private bool CompareTrees(Node Root1, Node Root2)
{
if (Root1 == null || Root2 == null)
return true;
if (Root1.Data != Root2.Data)
return false;
return CompareTrees(Root1.Left, Root2.Left) || CompareTrees(Root1.Right, Root2.Right);
}
public void TestSerialize()
{
var node = new Node();
node.Key = "test";
var payload = this.serializer.Marshal(node);
var result = this.serializer.Unmarshal(payload);
Assert.AreEqual(node, result);
}
public override Node eval(Node t, Environment env)
{
//arg1: set!
//arg2: variable
//arg3: value
env.assign(t.getCdr().getCar(), t.getCdr().getCdr().getCar().eval(env));
return new StringLit("set done");
}
private static void GetDepthRecurively(Node node, ref int depth)
{
if (node.Children.Count > 0)
{
depth += 1;
GetDepthRecurively(node.Children.FirstOrDefault(), ref depth);
}
}
// TODO: The method apply() should be defined in class Node
// to report an error. It should be overridden only in classes
// BuiltIn and Closure.
public override Node apply(Node args)
{
Node car = this.fun.getCdr().getCar();
Node cdr = this.fun.getCdr().getCdr();
Environment environment = new Environment(this.env);
Closure.pairup(car, args, environment);
return Util.begin(cdr, environment);
}
public override Node eval(Node t, Environment env)
{
Node bodystart = t.getCdr().getCar();
Node expression = t.getCdr().getCdr().getCar();
Environment e = new Environment(env);
bodystart = evalLetBody(bodystart, e); //Should we be returning bodystart?
return expression.eval(e); //Why return e?
}
public Node(int key)
{
this.leftNode = null;
this.rightNode = null;
this.key = key;
}
public override void print(Node t, int n, bool p)
{
Printer.printRegular(t, n, p);
}
public BuiltIn(Node s)
{
symbol = s;
}
public Node eval(Node t, Environment env)
{
Console.Error.WriteLine("Error in eval BuiltIN");
return(Nil.getInstance());
}
public override Node apply(Node args)
{
if (args == null)
{
return(null);
}
String symbolType = symbol.getName();
Node arg1 = args.getCar();
Node arg2 = args.getCdr();
if (arg1.isNull())
{
arg1 = Nil.getInstance();
}
if (arg2.isNull())
{
arg2 = Nil.getInstance();
}
else
{
arg2 = args.getCdr().getCar();
}
if (symbolType.Equals("b+"))
{
if (arg1.isNumber() & arg2.isNumber())
{
return(new IntLit(arg1.getValue() + arg2.getValue()));
}
else
{
return(new StringLit("Error: Both arguments must be numbers for b+"));
}
}
if (symbolType.Equals("b-"))
{
if (arg1.isNumber() & arg2.isNumber())
{
return(new IntLit(arg1.getValue() - arg2.getValue()));
}
else
{
return(new StringLit("Error: Both arguments must be numbers for b-"));
}
}
if (symbolType.Equals("b*"))
{
if (arg1.isNumber() & arg2.isNumber())
{
return(new IntLit(arg1.getValue() * arg2.getValue()));
}
else
{
return(new StringLit("Error: Both arguments must be numbers for b*"));
}
}
if (symbolType.Equals("b/"))
{
if (arg1.isNumber() & arg2.isNumber())
{
return(new IntLit(arg1.getValue() / arg2.getValue()));
}
else
{
return(new StringLit("Error: Both arguments must be numbers for b/"));
}
}
if (symbolType.Equals("b="))
{
if (arg1.isNumber() & arg2.isNumber())
{
return(new BoolLit(arg1.getValue() == arg2.getValue()));
}
else
{
return(new StringLit("Error: Both arguments must be numbers for b="));
}
}
if (symbolType.Equals("b<"))
{
if (arg1.isNumber() & arg2.isNumber())
{
return(new BoolLit(arg1.getValue() < arg2.getValue()));
}
else
{
return(new StringLit("Error: Both arguments must be numbers for b<"));
}
}
if (symbolType.Equals("null?"))
{
return(new BoolLit(arg1.isNull()));
}
if (symbolType.Equals("number?"))
{
return(new BoolLit(arg1.isNumber()));
}
if (symbolType.Equals("pair?"))
{
return(new BoolLit(arg1.isPair()));
}
if (symbolType.Equals("symbol?"))
{
return(new BoolLit(arg1.isSymbol()));
}
if (symbolType.Equals("procedure?"))
{
return(new BoolLit(arg1.isProcedure()));
}
if (symbolType.Equals("car"))
{
if (arg1.isNull())
{
return(arg1);
}
return(arg1.getCar());
}
if (symbolType.Equals("cdr"))
{
if (arg1.isNull())
{
return(arg1);
}
return(arg1.getCdr());
}
if (symbolType.Equals("set-car!"))
{
arg1.setCar(arg2);
return(arg1);
}
if (symbolType.Equals("set-cdr!"))
{
arg1.setCdr(arg2);
return(arg1);
}
if (symbolType.Equals("cons"))
{
return(new Cons(arg1, arg2));
}
if (symbolType.Equals("eq?"))
{
return(new BoolLit(arg1 == arg2));
}
if (symbolType.Equals("display"))
{
return(arg1);
}
if (symbolType.Equals("write"))
{
//write calls your pretting printer
arg1.print(0);
return(new StringLit(""));
}
if (symbolType.Equals("eval"))
{
//eval calls your C# eval() function
return(eval(arg1, env));
}
if (symbolType.Equals("apply"))
{
//apply calls your C# apply function
return(arg1.apply(arg2));
}
if (symbolType.Equals("newline"))
{
return(new StringLit(""));
}
if (symbolType.Equals("read"))
{
Scanner io = new Scanner(Console.In);
TreeBuilder tree = new TreeBuilder();
Parser parse = new Parser(io, tree);
Node theNode = (Node)parse.parseExp();
return(theNode);
}
if (symbolType.Equals("interaction-environment"))
{
env.print(0);
}
else
{
arg1.print(0);
return(Nil.getInstance());
}
return(Nil.getInstance());
}
public override Node eval(Environment env, Node args = null)
{
return(new StringLit(stringVal));
}
