[jackhill/mal.git] / impls / cs / step9_try.cs

using System;
using System.IO;
using System.Collections;
using System.Collections.Generic;
using Mal;
using MalVal = Mal.types.MalVal;
using MalString = Mal.types.MalString;
using MalSymbol = Mal.types.MalSymbol;
using MalInt = Mal.types.MalInt;
using MalList = Mal.types.MalList;
using MalVector = Mal.types.MalVector;
using MalHashMap = Mal.types.MalHashMap;
using MalFunc = Mal.types.MalFunc;
using Env = Mal.env.Env;

namespace Mal {
    class step9_try {
        // read
        static MalVal READ(string str) {
            return reader.read_str(str);
        }

        // eval
        public static bool starts_with(MalVal ast, string sym) {
            if (ast is MalList && !(ast is MalVector)) {
                MalList list = (MalList)ast;
                if (list.size() == 2 && list[0] is MalSymbol) {
                    MalSymbol a0 = (MalSymbol)list[0];
                    return a0.getName() == sym;
                }
            }
            return false;
        }

        public static MalVal qq_loop(MalList ast) {
            MalVal acc = new MalList();
            for(int i=ast.size()-1; 0<=i; i-=1) {
                MalVal elt = ast[i];
                if (starts_with(elt, "splice-unquote")) {
                    acc = new MalList(new MalSymbol("concat"), ((MalList)elt)[1], acc);
                } else {
                    acc = new MalList(new MalSymbol("cons"), quasiquote(elt), acc);
                }
            }
            return acc;
        }
        public static MalVal quasiquote(MalVal ast) {
            //  Check Vector subclass before List.
            if (ast is MalVector) {
                return new MalList(new MalSymbol("vec"), qq_loop(((MalList)ast)));
            } else if (starts_with(ast, "unquote")) {
                return ((MalList)ast)[1];
            } else if (ast is MalList) {
                return qq_loop((MalList)ast);
            } else if (ast is MalSymbol || ast is MalHashMap) {
                return new MalList(new MalSymbol("quote"), ast);
            } else {
                return ast;
            }
        }

        public static bool is_macro_call(MalVal ast, Env env) {
            if (ast is MalList) {
                MalVal a0 = ((MalList)ast)[0];
                if (a0 is MalSymbol &&
                    env.find((MalSymbol)a0) != null) {
                    MalVal mac = env.get((MalSymbol)a0);
                    if (mac is MalFunc &&
                        ((MalFunc)mac).isMacro()) {
                        return true;
                    }
                }
            }
            return false;
        }

        public static MalVal macroexpand(MalVal ast, Env env) {
            while (is_macro_call(ast, env)) {
                MalSymbol a0 = (MalSymbol)((MalList)ast)[0];
                MalFunc mac = (MalFunc) env.get(a0);
                ast = mac.apply(((MalList)ast).rest());
            }
            return ast;
        }

        static MalVal eval_ast(MalVal ast, Env env) {
            if (ast is MalSymbol) {
                return env.get((MalSymbol)ast);
            } else if (ast is MalList) {
                MalList old_lst = (MalList)ast;
                MalList new_lst = ast.list_Q() ? new MalList()
                                            : (MalList)new MalVector();
                foreach (MalVal mv in old_lst.getValue()) {
                    new_lst.conj_BANG(EVAL(mv, env));
                }
                return new_lst;
            } else if (ast is MalHashMap) {
                var new_dict = new Dictionary<string, MalVal>();
                foreach (var entry in ((MalHashMap)ast).getValue()) {
                    new_dict.Add(entry.Key, EVAL((MalVal)entry.Value, env));
                }
                return new MalHashMap(new_dict);
            } else {
                return ast;
            }
        }


        static MalVal EVAL(MalVal orig_ast, Env env) {
            MalVal a0, a1, a2, res;
            MalList el;

            while (true) {

            //Console.WriteLine("EVAL: " + printer._pr_str(orig_ast, true));
            if (!orig_ast.list_Q()) {
                return eval_ast(orig_ast, env);
            }

            // apply list
            MalVal expanded = macroexpand(orig_ast, env);
            if (!expanded.list_Q()) {
                return eval_ast(expanded, env);
            } 
            MalList ast = (MalList) expanded;

            if (ast.size() == 0) { return ast; }
            a0 = ast[0];

            String a0sym = a0 is MalSymbol ? ((MalSymbol)a0).getName()
                                           : "__<*fn*>__";

            switch (a0sym) {
            case "def!":
                a1 = ast[1];
                a2 = ast[2];
                res = EVAL(a2, env);
                env.set((MalSymbol)a1, res);
                return res;
            case "let*":
                a1 = ast[1];
                a2 = ast[2];
                MalSymbol key;
                MalVal val;
                Env let_env = new Env(env);
                for(int i=0; i<((MalList)a1).size(); i+=2) {
                    key = (MalSymbol)((MalList)a1)[i];
                    val = ((MalList)a1)[i+1];
                    let_env.set(key, EVAL(val, let_env));
                }
                orig_ast = a2;
                env = let_env;
                break;
            case "quote":
                return ast[1];
            case "quasiquoteexpand":
                return quasiquote(ast[1]);
            case "quasiquote":
                orig_ast = quasiquote(ast[1]);
                break;
            case "defmacro!":
                a1 = ast[1];
                a2 = ast[2];
                res = EVAL(a2, env);
                ((MalFunc)res).setMacro();
                env.set(((MalSymbol)a1), res);
                return res;
            case "macroexpand":
                a1 = ast[1];
                return macroexpand(a1, env);
            case "try*":
                try {
                    return EVAL(ast[1], env);
                } catch (Exception e) {
                    if (ast.size() > 2) {
                        MalVal exc;
                        a2 = ast[2];
                        MalVal a20 = ((MalList)a2)[0];
                        if (((MalSymbol)a20).getName() == "catch*") {
                            if (e is Mal.types.MalException) {
                                exc = ((Mal.types.MalException)e).getValue();
                            } else {
                                exc = new MalString(e.Message);
                            }
                            return EVAL(((MalList)a2)[2],
                                        new Env(env, ((MalList)a2).slice(1,2),
                                                new MalList(exc)));
                        }
                    }
                    throw e;
                }
            case "do":
                eval_ast(ast.slice(1, ast.size()-1), env);
                orig_ast = ast[ast.size()-1];
                break;
            case "if":
                a1 = ast[1];
                MalVal cond = EVAL(a1, env);
                if (cond == Mal.types.Nil || cond == Mal.types.False) {
                    // eval false slot form
                    if (ast.size() > 3) {
                        orig_ast = ast[3];
                    } else {
                        return Mal.types.Nil;
                    }
                } else {
                    // eval true slot form
                    orig_ast = ast[2];
                }
                break;
            case "fn*":
                MalList a1f = (MalList)ast[1];
                MalVal a2f = ast[2];
                Env cur_env = env;
                return new MalFunc(a2f, env, a1f,
                    args => EVAL(a2f, new Env(cur_env, a1f, args)) );
            default:
                el = (MalList)eval_ast(ast, env);
                var f = (MalFunc)el[0];
                MalVal fnast = f.getAst();
                if (fnast != null) {
                    orig_ast = fnast;
                    env = f.genEnv(el.rest());
                } else {
                    return f.apply(el.rest());
                }
                break;
            }

            }
        }

        // print
        static string PRINT(MalVal exp) {
            return printer._pr_str(exp, true);
        }

        // repl
        static void Main(string[] args) {
            var repl_env = new Mal.env.Env(null);
            Func<string, MalVal> RE = (string str) => EVAL(READ(str), repl_env);
            
            // core.cs: defined using C#
            foreach (var entry in core.ns) {
                repl_env.set(new MalSymbol(entry.Key), entry.Value);
            }
            repl_env.set(new MalSymbol("eval"), new MalFunc(
                        a => EVAL(a[0], repl_env)));
            int fileIdx = 0;
            if (args.Length > 0 && args[0] == "--raw") {
                Mal.readline.mode = Mal.readline.Mode.Raw;
                fileIdx = 1;
            }
            MalList _argv = new MalList();
            for (int i=fileIdx+1; i < args.Length; i++) {
                _argv.conj_BANG(new MalString(args[i]));
            }
            repl_env.set(new MalSymbol("*ARGV*"), _argv);

            // core.mal: defined using the language itself
            RE("(def! not (fn* (a) (if a false true)))");
            RE("(def! load-file (fn* (f) (eval (read-string (str \"(do \" (slurp f) \"\nnil)\")))))");
            RE("(defmacro! cond (fn* (& xs) (if (> (count xs) 0) (list 'if (first xs) (if (> (count xs) 1) (nth xs 1) (throw \"odd number of forms to cond\")) (cons 'cond (rest (rest xs)))))))");

            if (args.Length > fileIdx) {
                RE("(load-file \"" + args[fileIdx] + "\")");
                return;
            }

            // repl loop
            while (true) {
                string line;
                try {
                    line = Mal.readline.Readline("user> ");
                    if (line == null) { break; }
                    if (line == "") { continue; }
                } catch (IOException e) {
                    Console.WriteLine("IOException: " + e.Message);
                    break;
                }
                try {
                    Console.WriteLine(PRINT(RE(line)));
                } catch (Mal.types.MalContinue) {
                    continue;
                } catch (Mal.types.MalException e) {
                    Console.WriteLine("Error: " +
                            printer._pr_str(e.getValue(), false));
                    continue;
                } catch (Exception e) {
                    Console.WriteLine("Error: " + e.Message);
                    Console.WriteLine(e.StackTrace);
                    continue;
                }
            }
        }
    }
}
Commit	Line	Data
faee4d12 JM	1	using System;
	2	using System.IO;
	3	using System.Collections;
	4	using System.Collections.Generic;
	5	using Mal;
faee4d12 JM	6	using MalVal = Mal.types.MalVal;
	7	using MalString = Mal.types.MalString;
	8	using MalSymbol = Mal.types.MalSymbol;
c3b508af	9	using MalInt = Mal.types.MalInt;
faee4d12 JM	10	using MalList = Mal.types.MalList;
	11	using MalVector = Mal.types.MalVector;
	12	using MalHashMap = Mal.types.MalHashMap;
c3b508af	13	using MalFunc = Mal.types.MalFunc;
faee4d12 JM	14	using Env = Mal.env.Env;
	15
	16	namespace Mal {
01c97316	17	class step9_try {
faee4d12 JM	18	// read
	19	static MalVal READ(string str) {
	20	return reader.read_str(str);
	21	}
	22
	23	// eval
fbfe6784 NB	24	public static bool starts_with(MalVal ast, string sym) {
	25	if (ast is MalList && !(ast is MalVector)) {
	26	MalList list = (MalList)ast;
	27	if (list.size() == 2 && list[0] is MalSymbol) {
	28	MalSymbol a0 = (MalSymbol)list[0];
	29	return a0.getName() == sym;
	30	}
	31	}
	32	return false;
faee4d12 JM	33	}
faee4d12 JM	34
fbfe6784 NB	35	public static MalVal qq_loop(MalList ast) {
	36	MalVal acc = new MalList();
	37	for(int i=ast.size()-1; 0<=i; i-=1) {
	38	MalVal elt = ast[i];
	39	if (starts_with(elt, "splice-unquote")) {
	40	acc = new MalList(new MalSymbol("concat"), ((MalList)elt)[1], acc);
	41	} else {
	42	acc = new MalList(new MalSymbol("cons"), quasiquote(elt), acc);
	43	}
	44	}
	45	return acc;
	46	}
faee4d12	47	public static MalVal quasiquote(MalVal ast) {
fbfe6784 NB	48	// Check Vector subclass before List.
	49	if (ast is MalVector) {
	50	return new MalList(new MalSymbol("vec"), qq_loop(((MalList)ast)));
	51	} else if (starts_with(ast, "unquote")) {
	52	return ((MalList)ast)[1];
	53	} else if (ast is MalList) {
	54	return qq_loop((MalList)ast);
	55	} else if (ast is MalSymbol \|\| ast is MalHashMap) {
faee4d12 JM	56	return new MalList(new MalSymbol("quote"), ast);
faee4d12 JM	57	} else {
fbfe6784	58	return ast;
faee4d12 JM	59	}
	60	}
	61
	62	public static bool is_macro_call(MalVal ast, Env env) {
	63	if (ast is MalList) {
	64	MalVal a0 = ((MalList)ast)[0];
	65	if (a0 is MalSymbol &&
b8ee29b2 JM	66	env.find((MalSymbol)a0) != null) {
b8ee29b2 JM	67	MalVal mac = env.get((MalSymbol)a0);
c3b508af JM	68	if (mac is MalFunc &&
c3b508af JM	69	((MalFunc)mac).isMacro()) {
faee4d12 JM	70	return true;
	71	}
	72	}
	73	}
	74	return false;
	75	}
	76
	77	public static MalVal macroexpand(MalVal ast, Env env) {
	78	while (is_macro_call(ast, env)) {
	79	MalSymbol a0 = (MalSymbol)((MalList)ast)[0];
b8ee29b2	80	MalFunc mac = (MalFunc) env.get(a0);
faee4d12 JM	81	ast = mac.apply(((MalList)ast).rest());
	82	}
	83	return ast;
	84	}
	85
	86	static MalVal eval_ast(MalVal ast, Env env) {
	87	if (ast is MalSymbol) {
b8ee29b2	88	return env.get((MalSymbol)ast);
faee4d12 JM	89	} else if (ast is MalList) {
	90	MalList old_lst = (MalList)ast;
	91	MalList new_lst = ast.list_Q() ? new MalList()
	92	: (MalList)new MalVector();
	93	foreach (MalVal mv in old_lst.getValue()) {
	94	new_lst.conj_BANG(EVAL(mv, env));
	95	}
	96	return new_lst;
	97	} else if (ast is MalHashMap) {
	98	var new_dict = new Dictionary<string, MalVal>();
	99	foreach (var entry in ((MalHashMap)ast).getValue()) {
	100	new_dict.Add(entry.Key, EVAL((MalVal)entry.Value, env));
	101	}
	102	return new MalHashMap(new_dict);
	103	} else {
	104	return ast;
	105	}
	106	}
	107
	108
	109	static MalVal EVAL(MalVal orig_ast, Env env) {
	110	MalVal a0, a1, a2, res;
	111	MalList el;
	112
	113	while (true) {
	114
b8ee29b2	115	//Console.WriteLine("EVAL: " + printer._pr_str(orig_ast, true));
faee4d12 JM	116	if (!orig_ast.list_Q()) {
	117	return eval_ast(orig_ast, env);
	118	}
	119
	120	// apply list
	121	MalVal expanded = macroexpand(orig_ast, env);
36e287b5 JM	122	if (!expanded.list_Q()) {
	123	return eval_ast(expanded, env);
	124	}
faee4d12 JM	125	MalList ast = (MalList) expanded;
	126
	127	if (ast.size() == 0) { return ast; }
	128	a0 = ast[0];
	129
	130	String a0sym = a0 is MalSymbol ? ((MalSymbol)a0).getName()
	131	: "__<fn>__";
	132
	133	switch (a0sym) {
	134	case "def!":
	135	a1 = ast[1];
	136	a2 = ast[2];
	137	res = EVAL(a2, env);
b8ee29b2	138	env.set((MalSymbol)a1, res);
faee4d12 JM	139	return res;
	140	case "let*":
	141	a1 = ast[1];
	142	a2 = ast[2];
	143	MalSymbol key;
	144	MalVal val;
	145	Env let_env = new Env(env);
	146	for(int i=0; i<((MalList)a1).size(); i+=2) {
	147	key = (MalSymbol)((MalList)a1)[i];
	148	val = ((MalList)a1)[i+1];
b8ee29b2	149	let_env.set(key, EVAL(val, let_env));
faee4d12	150	}
6301e0b6 JM	151	orig_ast = a2;
	152	env = let_env;
	153	break;
faee4d12 JM	154	case "quote":
faee4d12 JM	155	return ast[1];
fbfe6784 NB	156	case "quasiquoteexpand":
fbfe6784 NB	157	return quasiquote(ast[1]);
faee4d12	158	case "quasiquote":
6301e0b6 JM	159	orig_ast = quasiquote(ast[1]);
6301e0b6 JM	160	break;
faee4d12 JM	161	case "defmacro!":
	162	a1 = ast[1];
	163	a2 = ast[2];
	164	res = EVAL(a2, env);
c3b508af	165	((MalFunc)res).setMacro();
b8ee29b2	166	env.set(((MalSymbol)a1), res);
faee4d12 JM	167	return res;
	168	case "macroexpand":
	169	a1 = ast[1];
	170	return macroexpand(a1, env);
	171	case "try*":
	172	try {
	173	return EVAL(ast[1], env);
	174	} catch (Exception e) {
	175	if (ast.size() > 2) {
	176	MalVal exc;
	177	a2 = ast[2];
	178	MalVal a20 = ((MalList)a2)[0];
	179	if (((MalSymbol)a20).getName() == "catch*") {
8cb5cda4 JM	180	if (e is Mal.types.MalException) {
8cb5cda4 JM	181	exc = ((Mal.types.MalException)e).getValue();
faee4d12	182	} else {
6c4cc8ad	183	exc = new MalString(e.Message);
faee4d12 JM	184	}
	185	return EVAL(((MalList)a2)[2],
	186	new Env(env, ((MalList)a2).slice(1,2),
	187	new MalList(exc)));
	188	}
	189	}
	190	throw e;
	191	}
	192	case "do":
	193	eval_ast(ast.slice(1, ast.size()-1), env);
	194	orig_ast = ast[ast.size()-1];
	195	break;
	196	case "if":
	197	a1 = ast[1];
	198	MalVal cond = EVAL(a1, env);
8cb5cda4	199	if (cond == Mal.types.Nil \|\| cond == Mal.types.False) {
faee4d12 JM	200	// eval false slot form
	201	if (ast.size() > 3) {
	202	orig_ast = ast[3];
	203	} else {
8cb5cda4	204	return Mal.types.Nil;
faee4d12 JM	205	}
	206	} else {
	207	// eval true slot form
	208	orig_ast = ast[2];
	209	}
	210	break;
	211	case "fn*":
	212	MalList a1f = (MalList)ast[1];
	213	MalVal a2f = ast[2];
	214	Env cur_env = env;
c3b508af	215	return new MalFunc(a2f, env, a1f,
faee4d12 JM	216	args => EVAL(a2f, new Env(cur_env, a1f, args)) );
	217	default:
	218	el = (MalList)eval_ast(ast, env);
c3b508af	219	var f = (MalFunc)el[0];
faee4d12 JM	220	MalVal fnast = f.getAst();
	221	if (fnast != null) {
	222	orig_ast = fnast;
	223	env = f.genEnv(el.rest());
	224	} else {
	225	return f.apply(el.rest());
	226	}
	227	break;
	228	}
	229
	230	}
	231	}
	232
	233	// print
	234	static string PRINT(MalVal exp) {
	235	return printer._pr_str(exp, true);
	236	}
	237
86b689f3	238	// repl
faee4d12	239	static void Main(string[] args) {
c3b508af JM	240	var repl_env = new Mal.env.Env(null);
c3b508af JM	241	Func<string, MalVal> RE = (string str) => EVAL(READ(str), repl_env);
faee4d12	242
8cb5cda4	243	// core.cs: defined using C#
faee4d12	244	foreach (var entry in core.ns) {
b8ee29b2	245	repl_env.set(new MalSymbol(entry.Key), entry.Value);
faee4d12	246	}
b8ee29b2 JM	247	repl_env.set(new MalSymbol("eval"), new MalFunc(
b8ee29b2 JM	248	a => EVAL(a[0], repl_env)));
dbbac62f	249	int fileIdx = 0;
aaba2493 JM	250	if (args.Length > 0 && args[0] == "--raw") {
aaba2493 JM	251	Mal.readline.mode = Mal.readline.Mode.Raw;
dbbac62f	252	fileIdx = 1;
aaba2493	253	}
86b689f3	254	MalList _argv = new MalList();
dbbac62f	255	for (int i=fileIdx+1; i < args.Length; i++) {
86b689f3 JM	256	_argv.conj_BANG(new MalString(args[i]));
86b689f3 JM	257	}
b8ee29b2	258	repl_env.set(new MalSymbol("ARGV"), _argv);
faee4d12	259
8cb5cda4	260	// core.mal: defined using the language itself
c3b508af	261	RE("(def! not (fn* (a) (if a false true)))");
e6d41de4	262	RE("(def! load-file (fn* (f) (eval (read-string (str \"(do \" (slurp f) \"\nnil)\")))))");
c3b508af	263	RE("(defmacro! cond (fn* (& xs) (if (> (count xs) 0) (list 'if (first xs) (if (> (count xs) 1) (nth xs 1) (throw \"odd number of forms to cond\")) (cons 'cond (rest (rest xs)))))))");
faee4d12	264
faee4d12	265	if (args.Length > fileIdx) {
c3b508af	266	RE("(load-file \"" + args[fileIdx] + "\")");
faee4d12 JM	267	return;
faee4d12 JM	268	}
c3b508af	269
86b689f3	270	// repl loop
faee4d12 JM	271	while (true) {
	272	string line;
	273	try {
c3b508af	274	line = Mal.readline.Readline("user> ");
faee4d12	275	if (line == null) { break; }
c3b508af	276	if (line == "") { continue; }
faee4d12 JM	277	} catch (IOException e) {
	278	Console.WriteLine("IOException: " + e.Message);
	279	break;
	280	}
	281	try {
c3b508af	282	Console.WriteLine(PRINT(RE(line)));
8cb5cda4	283	} catch (Mal.types.MalContinue) {
faee4d12	284	continue;
8cb5cda4	285	} catch (Mal.types.MalException e) {
faee4d12 JM	286	Console.WriteLine("Error: " +
	287	printer._pr_str(e.getValue(), false));
	288	continue;
	289	} catch (Exception e) {
	290	Console.WriteLine("Error: " + e.Message);
	291	Console.WriteLine(e.StackTrace);
	292	continue;
	293	}
	294	}
	295	}
	296	}
	297	}