internal static MalType eval_ast(MalType ast, Environment environment)
{
var symbol = ast as MalSymbol;
if (symbol != null)
{
if (environment.HasSymbol(symbol))
{
return(environment.GetSymbol(symbol));
}
return(symbol);
}
var hash = ast as MalHashMap <MalType, MalType>;
if (hash != null)
{
var items = hash.GetItems();
Dictionary <MalType, MalType> output = items.Keys.ToDictionary(key => key, key => Eval(items[key], environment));
return(hash.Repackage(output));
}
var listlike = ast as AbstractMalListlike <MalType>;
if (listlike != null)
{
List <MalType> output = listlike.GetItems().Select(item => Eval(item, environment)).ToList();
return(listlike.Repackage(output));
}
return(ast);
}
private MalType ReadMetaData()
{
_tokens.RemoveAt(0); // remove the ^
MalType meta = ReadForm();
MalType item = ReadForm();
return(new MalMetaData(item, meta));
}
public static MalType Eval(MalType arg, Environment environment)
{
var argList = arg as MalList <MalType>;
bool breakHere = (arg.ToString() == "(+ 7 8)");
if (argList != null)
{
if (argList.GetItems()[0].Equals(new MalSymbol("def!")))
{
return(environment.Set(argList.GetItems()[1] as MalSymbol, Eval(argList.GetItems()[2], environment)));
}
if (argList.GetItems()[0].Equals(new MalSymbol("let*")))
{
var letEnv = Environment.Make(environment);
var listLike = argList.GetItems()[1] as AbstractMalListlike <MalType>;
if (listLike != null)
{
var letParams = listLike.GetItems();
int i = 0;
do
{
var key = letParams[i] as MalSymbol;
var value = Eval(letParams[i + 1], letEnv);
letEnv.Set(key, value);
i = i + 2;
} while (i < letParams.Count);
}
return(Eval(argList.GetItems()[2], letEnv));
}
MalList <MalType> newEvaluatedList = ((MalList <MalType>)eval_ast(arg, environment));
var items = newEvaluatedList.GetItems();
var firstItem = items.First() as MalSymbol;
var restItems = new MalList <MalType>(items.GetRange(1, items.Count - 1));
var application = environment.Apply(firstItem, restItems);
Console.WriteLine("Result of apply: " + application);
return(application);
}
/*
* ast is not a list: then return the result of calling eval_ast on it.
*/
return(eval_ast(arg, environment));
}
// private static MalType Eval(MalType arg, Environment environment)
// {
// if (arg is MalList<MalType>)
// {
// MalList<MalType> newEvaluatedList = ((MalList<MalType>)eval_ast(arg, environment));
// var items = newEvaluatedList.GetItems();
// MalType firstItem = items.First();
// var restItems = new MalList<MalType>(items.GetRange(1, items.Count - 1));
// return environment.Apply((MalSymbol)firstItem, restItems);
// }
// /*
// * ast is not a list: then return the result of calling eval_ast on it.
// */
// return eval_ast(arg, environment);
// }
private static string Print(MalType arg)
{
return(Printer.PrStr(arg));
}
private static MalType Eval(MalType arg)
{
return(arg);
}
public MalDeref(MalType val)
{
_val = val;
}
public MalMetaData(MalType a, MalType b)
{
_a = a;
_b = b;
}
public MalQuasiQuote(MalType val)
{
_val = val;
}
public MalUnquote(MalType val)
{
_val = val;
}
public MalSpliceUnquote(MalType input)
{
_val = input;
}
public MalQuote(MalType input)
{
_val = input;
}
public MalType Set(MalSymbol key, MalType value)
{
_dict[key] = value;
return(value);
}
