public void SetValue(Symbol key, SchemeObject value, bool isDefinition)
{
SchemeEnvironment env = this;
if (!isDefinition)
{
for (; env != null; env = env.parent)
if (env.dictionary.ContainsKey(key))
break;
if (env == null)
throw new InvalidSyntaxException();
}
env.dictionary[key] = value;
}
private static Datum BuildRestArgument(SchemeObject[] arguments, int index)
{
if (index == arguments.Length)
return SchemeNull.Instance;
Pair current = new Pair(SchemeNull.Instance, SchemeNull.Instance);
Pair list = current;
for (; index < arguments.Length - 1; index++)
{
current.Car = arguments[index];
current.Cdr = new Pair(SchemeNull.Instance, SchemeNull.Instance);
current = (Pair)current.Cdr;
}
current.Car = arguments[index];
return list;
}
private static SchemeEnvironment BuildCallEnvironment(SchemeObject[] arguments, Closure closure)
{
ReadOnlyCollection<Variable> parameters = closure.Parameters;
Variable restParameter = closure.RestParameter;
if (arguments.Length != parameters.Count && restParameter == null)
throw InvalidSyntaxException.Format(Strings.IncorrectArgumentCount, parameters.Count, arguments.Length);
if (arguments.Length < parameters.Count)
throw InvalidSyntaxException.Format(Strings.TooFewArguments, parameters.Count, arguments.Length);
SchemeEnvironment result = new SchemeEnvironment(closure.Environment);
int index = 0;
for (; index < parameters.Count; index++)
result.Add(parameters[index], arguments[index]);
if (restParameter != null)
{
Datum restArgument = BuildRestArgument(arguments, index);
result.Add(closure.RestParameter, restArgument);
}
return result;
}
public void Add(Symbol key, SchemeObject value)
{
this.dictionary[key] = value;
}
public void Add(Variable key, SchemeObject value)
{
Add(key.Symbol, value);
}