public static IDictionary <Symbol, object> CreateBuiltins(Interpreter interpreter)
{
var builtins = new Dictionary <Symbol, object>();
builtins[Symbol.FromString("+")] = new NativeProcedure(Utils.MakeVariadic(Add), "+");
builtins[Symbol.FromString("-")] = new NativeProcedure(Utils.MakeVariadic(Minus), "-");
builtins[Symbol.FromString("*")] = new NativeProcedure(Utils.MakeVariadic(Multiply), "*");
builtins[Symbol.FromString("/")] = new NativeProcedure(Utils.MakeVariadic(Divide), "/");
builtins[Symbol.FromString("=")] = NativeProcedure.Create <double, double, bool>((x, y) => x == y, "=");
builtins[Symbol.FromString("<")] = NativeProcedure.Create <double, double, bool>((x, y) => x < y, "<");
builtins[Symbol.FromString("<=")] = NativeProcedure.Create <double, double, bool>((x, y) => x <= y, "<=");
builtins[Symbol.FromString(">")] = NativeProcedure.Create <double, double, bool>((x, y) => x > y, ">");
builtins[Symbol.FromString(">=")] = NativeProcedure.Create <double, double, bool>((x, y) => x >= y, ">=");
builtins[Symbol.FromString("eq?")] = NativeProcedure.Create <object, object, bool>((x, y) => object.ReferenceEquals(x, y), "eq?");
builtins[Symbol.FromString("equal?")] = NativeProcedure.Create <object, object, bool>(EqualImpl, "equal?");
builtins[Symbol.FromString("boolean?")] = NativeProcedure.Create <object, bool>(x => x is bool, "boolean?");
builtins[Symbol.FromString("num?")] = NativeProcedure.Create <object, bool>(x => x is int || x is double, "num?");
builtins[Symbol.FromString("string?")] = NativeProcedure.Create <object, bool>(x => x is string, "string?");
builtins[Symbol.FromString("symbol?")] = NativeProcedure.Create <object, bool>(x => x is Symbol, "symbol?");
builtins[Symbol.FromString("list?")] = NativeProcedure.Create <object, bool>(x => x is List <object>, "list?");
builtins[Symbol.FromString("map")] = NativeProcedure.Create <ICallable, List <object>, List <object> >((func, ls) => ls.Select(x => func.Call(new List <object> {
x
})).ToList());
builtins[Symbol.FromString("reverse")] = NativeProcedure.Create <List <object>, List <object> >(ls => ls.Reverse <object>().ToList());
builtins[Symbol.FromString("range")] = new NativeProcedure(RangeImpl, "range");
builtins[Symbol.FromString("apply")] = NativeProcedure.Create <ICallable, List <object>, object>((proc, args) => proc.Call(args), "apply");
builtins[Symbol.FromString("list")] = new NativeProcedure(args => args, "list");
builtins[Symbol.FromString("list-ref")] = NativeProcedure.Create <List <object>, int, object>((ls, idx) => ls[idx]);
builtins[Symbol.FromString("length")] = NativeProcedure.Create <List <object>, int>(list => list.Count, "length");
builtins[Symbol.FromString("car")] = NativeProcedure.Create <List <object>, object>(args => args[0], "car");
builtins[Symbol.FromString("cdr")] = NativeProcedure.Create <List <object>, List <object> >(args => args.Skip(1).ToList(), "cdr");
builtins[Symbol.CONS] = NativeProcedure.Create <object, List <object>, List <object> >((x, ys) => Enumerable.Concat(new[] { x }, ys).ToList(), "cons");
builtins[Symbol.FromString("not")] = NativeProcedure.Create <bool, bool>(x => !x, "not");
builtins[Symbol.APPEND] = NativeProcedure.Create <List <object>, List <object>, List <object> >((l1, l2) => Enumerable.Concat(l1, l2).ToList(), "append");
builtins[Symbol.FromString("null")] = NativeProcedure.Create <object>(() => (object)null, "null");
builtins[Symbol.FromString("null?")] = NativeProcedure.Create <object, bool>(x => x is List <object> && ((List <object>)x).Count == 0, "null?");
builtins[Symbol.FromString("assert")] = new NativeProcedure(AssertImpl, "assert");
builtins[Symbol.FromString("load")] = NativeProcedure.Create <string, None>(filename => LoadImpl(interpreter, filename), "load");
builtins[Symbol.FromString("call/cc")] = NativeProcedure.Create <ICallable, object>(Continuation.CallWithCurrentContinuation, "call/cc");
return(builtins);
}
public static object CallWithCurrentContinuation(ICallable fc1)
{
var ccc = new Continuation {
Stack = new StackTrace(), Thread = Thread.CurrentThread
};
try
{
var exitproc = NativeProcedure.Create <object, object>(v =>
{
var f1 = new StackTrace().GetFrames();
var c1 = ccc.Stack.GetFrames();
var offset = f1.Length - c1.Length;
if (ccc.Thread == Thread.CurrentThread)
{
for (int i = c1.Length - 1; i >= 0; i--)
{
if (c1[i].GetMethod() != f1[i + offset].GetMethod())
{
throw new NotImplementedException("not supported, continuation called outside dynamic extent");
}
}
}
ccc.Value = v;
throw ccc;
});
return(fc1.Call(new List <object> {
exitproc
}));
}
catch (Continuation c)
{
if (ccc == c)
{
return(c.Value);
}
else
{
throw;
}
}
}
public static void Main(string[] args)
{
Interpreter.CreateSymbolTableDelegate extension = _ => new Dictionary <Symbol, object>()
{
{ Symbol.FromString("say-hi"), NativeProcedure.Create <Function>(() => name => $"Hello {name}!") },
{ Symbol.FromString("truncate-string"), NativeProcedure.Create <int, Function>(len => input => ((string)input).Substring(0, len)) },
{ Symbol.FromString("dump"), NativeProcedure.Create <object>(() => Symbol.AllSymbols()) },
{ Symbol.FromString("print"), NativeProcedure.Create <object, object>((arg) => Print(arg)) },
{ Symbol.FromString("typeof"), NativeProcedure.Create <object, object>((arg) => {
if (null == arg)
{
return(null);
}
return(arg.GetType());
}) }
};
// TODO: math
/*
* 1 三角函数
* double sin (double x); x的正弦值
* double cos (double x); x的余弦值
* double tan (double x); x的正切值
*
* 2 反三角函数
* double asin (double x); 结果介于[-PI/2, PI/2]，x值域为[-1,1]
* double acos (double x); 结果介于[0, PI],x值域为[-1,1]
* double atan (double x); 反正切(主值), 结果介于[-PI/2, PI/2]
* double atan2 (double y, double x); 反正切(整圆值), 结果介于[-PI, PI]
*
* 3 双曲三角函数
* double sinh (double x); x的双曲正弦值
* double cosh (double x); x的双曲余弦值
* double tanh (double x); x的双曲正切值
*
* 4 指数与对数
* double exp (double x); 幂函数e^x
* double pow (double x, double y); x^y，如果x=0且y<=0,或者x<0且y不是整型数，将产生定义域错误
* double sqrt (double x); x的平方根，其中x>=0
* double log (double x); 以e为底的对数,自然对数，x>0
* double log10 (double x); 以10为底的对数，x>0
*
* 5 取整
* double ceil (double x); 取上整
* double floor (double x); 取下整
*
* 6 绝对值
* double fabs (double x); x的绝对值
*
* 7 标准化浮点数
* double frexp (double x, int *exp); 标准化浮点数, x = f * 2^exp, 已知x求f, exp ( x介于[0.5, 1] )并返回f值
* double ldexp (double x, int exp); 与frexp相反, 已知x, exp求x*2^exp
*
* 8 取整与取余
* double modf (double x, double *ip); 将参数的整数部分通过指针回传, 返回小数部分，整数部分保存在*ip中
* double fmod (double x, double y); 返回两参数相除x/y的余数,符号与x相同。如果y为0，则结果与具体的额实现有关。
*/
// max, min, abs
// TODO: logic(and, or)
// TODO: c# Reflection
// TODO: string operations (upper, lower, substring, regex)
// TODO: hash/dict
// TODO: set-car! set-cdr!
// TODO: alist
// misc: incf decf ++ -- to-delegate
// Console.WriteLine("Args: {0}#{1} {2}", args, args.Length, args[0]);
if (args.Length > 0 && File.Exists(args[0]))
{
// evaluate input file's content
var file = args[0];
// Console.WriteLine("Eval file ...");
var interpreter = new Interpreter(new[] { extension }, new ReadOnlyFileSystemAccessor());
using (TextReader reader = new StreamReader(file))
{
object res = interpreter.Evaluate(reader);
Console.WriteLine(Utils.PrintExpr(res));
}
}
else
{
// starts the REPL
var interpreter = new Interpreter(new[] { extension }, new ReadOnlyFileSystemAccessor());
var headers = new[]
{
"-----------------------------------------------",
"| Schemy - Scheme as a Configuration Language |",
"| Press Ctrl-C to exit |",
"-----------------------------------------------",
};
interpreter.REPL(Console.In, Console.Out, "Schemy> ", headers);
}
}
