public void RemoveBinding(ScheminAtom symbol)
{
if (bindings.ContainsKey(symbol.Name))
{
bindings.Remove(symbol.Name);
}
}
public void AddBinding(ScheminAtom symbol, IScheminType type)
{
if (bindings.ContainsKey(symbol.Name))
{
bindings[symbol.Name] = type;
}
else
{
bindings.Add(symbol.Name, type);
}
}
public IScheminType GetValue(ScheminAtom symbol)
{
Environment parent = this;
while (parent != null)
{
IScheminType value;
parent.bindings.TryGetValue(symbol.Name, out value);
if (value != null)
{
return parent.bindings[symbol.Name];
}
parent = parent.parent;
}
return null;
}
private IScheminType ConvertAtom(ScheminAtom atom, Token token)
{
switch (atom.Name)
{
// these are special forms that can't be bound to symbols, they're always primitives
case "lambda":
return new ScheminPrimitive("lambda", token);
case "define":
return new ScheminPrimitive("define", token);
case "define-rewriter":
return new ScheminPrimitive("define-rewriter", token);
case "quote":
return new ScheminPrimitive("quote", token);
case "unquote":
return new ScheminPrimitive("unquote", token);
case "unquote-splicing":
return new ScheminPrimitive("unquote-splicing", token);
case "quasiquote":
return new ScheminPrimitive("quasiquote", token);
case "begin":
return new ScheminPrimitive("begin", token);
case "if":
return new ScheminPrimitive("if", token);
case "or":
return new ScheminPrimitive("or", token);
case "and":
return new ScheminPrimitive("and", token);
case "cond":
return new ScheminPrimitive("cond", token);
case "let":
return new ScheminPrimitive("let", token);
case "letrec":
return new ScheminPrimitive("letrec", token);
case "let*":
return new ScheminPrimitive("let*", token);
case "set!":
return new ScheminPrimitive("set!", token);
case "call/cc":
return new ScheminPrimitive("call/cc", token);
default:
return atom;
}
}
private int AdjustLevelEnter(ScheminAtom first, int currentLevel)
{
if (first != null)
{
if (first.Name == "quasiquote")
{
currentLevel++;
}
else if (first.Name == "unquote")
{
currentLevel--;
}
else if (first.Name == "unquote-splicing")
{
currentLevel--;
}
}
return currentLevel;
}
private void DefinePrimitives(Environment env)
{
foreach (KeyValuePair<string, Primitive> kvp in PrimitiveFactory.Primitives)
{
ScheminAtom symbol = new ScheminAtom(kvp.Key);
ScheminPrimitive prim = new ScheminPrimitive(kvp.Key);
env.AddBinding(symbol, prim);
}
var prebound_schemin = new List<string>();
prebound_schemin.Add(ScheminPrimitives.Map);
prebound_schemin.Add(ScheminPrimitives.Filter);
prebound_schemin.Add(ScheminPrimitives.Foldl);
prebound_schemin.Add(ScheminPrimitives.Foldr);
prebound_schemin.Add(ScheminPrimitives.Not);
prebound_schemin.Add(ScheminPrimitives.Id);
prebound_schemin.Add(ScheminPrimitives.Flip);
prebound_schemin.Add(ScheminPrimitives.Fold);
prebound_schemin.Add(ScheminPrimitives.Unfold);
prebound_schemin.Add(ScheminPrimitives.Reverse);
prebound_schemin.Add(ScheminPrimitives.Curry);
prebound_schemin.Add(ScheminPrimitives.Compose);
prebound_schemin.Add(ScheminPrimitives.Zero);
prebound_schemin.Add(ScheminPrimitives.Positive);
prebound_schemin.Add(ScheminPrimitives.Negative);
prebound_schemin.Add(ScheminPrimitives.Odd);
prebound_schemin.Add(ScheminPrimitives.Even);
prebound_schemin.Add(ScheminPrimitives.CallWithCC);
prebound_schemin.Add(ScheminPrimitives.Error);
prebound_schemin.Add(ScheminPrimitives.Sum);
prebound_schemin.Add(ScheminPrimitives.Product);
prebound_schemin.Add(ScheminPrimitives.Max);
prebound_schemin.Add(ScheminPrimitives.Min);
prebound_schemin.Add(ScheminPrimitives.Caddr);
prebound_schemin.Add(ScheminPrimitives.DefineMacro);
Tokenize.Tokenizer t = new Tokenize.Tokenizer();
Schemin.Parse.Parser p = new Parse.Parser();
foreach (string primitive in prebound_schemin)
{
var tokens = t.Tokenize(primitive);
var ast = p.Parse(tokens, false);
Evaluate(ast);
}
}