2 using System.Collections;
3 using System.Collections.Generic;
9 public class Xexpression
11 private static int debug_depth = 0;
13 public static int DebugDepth {
14 get { return debug_depth; }
15 set { debug_depth = value; }
18 public struct Symbol : IEquatable<Symbol>
20 private static NameTable nt = new NameTable ();
24 public Symbol (string str) { name = nt.Add (str); }
26 public static implicit operator Symbol (string str)
28 return new Symbol (str);
31 public static implicit operator string (Symbol sym) { return sym.name; }
33 public static bool operator== (Symbol n1, Symbol n2)
35 return (object) n1.name == (object) n2.name;
38 public static bool operator!= (Symbol n1, Symbol n2)
40 return (object) n1.name != (object) n2.name;
43 public static bool operator== (Symbol n1, string n2)
45 return (object) n1.name == (object) n2;
48 public static bool operator!= (Symbol n1, string n2)
50 return (object) n1.name != (object) n2;
53 public static bool operator== (string n1, Symbol n2)
55 return (object) n1 == (object) n2.name;
58 public static bool operator!= (string n1, Symbol n2)
60 return (object) n1 != (object) n2.name;
63 public bool Equals (Symbol name)
65 return Object.ReferenceEquals (this.name, name.name);
68 public override bool Equals (object obj)
70 return Object.ReferenceEquals (this.name, obj);
73 public override int GetHashCode ()
75 return name.GetHashCode ();
78 public static NameTable NameTable { get { return nt; } }
80 public override string ToString () { return name; }
83 private static Symbol Qexpr = "expr";
85 private static Symbol Qnull = "";
86 private static Symbol Qfuncall = "funcall";
87 private static Symbol Qinteger = "integer";
88 private static Symbol Qstring = "string";
89 private static Symbol Qsymbol = "symbol";
90 private static Symbol Qlist = "list";
92 public static Symbol Qdefun = "defun";
93 public static Symbol Qdefmacro = "defmacro";
94 private static Symbol Qfname = "fname";
95 private static Symbol Qargs = "args";
96 private static Symbol Qfixed = "fixed";
97 private static Symbol Qoptional = "optional";
98 private static Symbol Qrest = "rest";
100 public static Symbol Qdefvar = "defvar";
101 private static Symbol Qvname = "vname";
102 private static Symbol Qdescription = "description";
103 private static Symbol Qrange = "range";
105 public abstract class Function
108 public int min_arg, max_arg;
110 public Function () { }
112 public Function (Symbol name, int min_arg, int max_arg)
115 this.min_arg = min_arg;
116 this.max_arg = max_arg;
119 public abstract Term Call (Domain domain, Variable vari, Term[] args);
121 public override string ToString ()
126 internal class Subroutine : Function
128 public Builtin builtin;
131 public Subroutine (Builtin builtin, Symbol name, bool setvar,
132 int min_arg, int max_arg)
133 : base (name, min_arg, max_arg)
135 this.builtin = builtin;
136 this.setvar = setvar;
139 public override Term Call (Domain domain, Variable vari, Term[] args)
143 args = (Term[]) args.Clone ();
144 for (int i = 0; i < args.Length; i++)
146 args[i] = args[i].Eval (domain);
151 return builtin (domain, vari, args);
155 internal class SpecialForm : Function
157 public Builtin builtin;
159 public SpecialForm (Builtin builtin, Symbol name,
160 int min_arg, int max_arg)
161 : base (name, min_arg, max_arg)
163 this.builtin = builtin;
166 public override Term Call (Domain domain, Variable vari, Term[] args)
168 return builtin (domain, vari, args);
172 private static void parse_head (Domain domain, XmlNode node,
174 out int min_arg, out int max_arg,
180 name = node.Attributes[Qfname].Value;
182 node = node.FirstChild;
183 if (node != null && node.Name == Qargs)
186 for (n = node.FirstChild; n != null; n = n.NextSibling)
188 if (n.Name == Qfixed)
190 else if (n.Name == Qoptional)
192 else if (n.Name == Qrest)
195 throw new Exception ("Invalid argument type: " + n);
198 max_arg = nfixed + noptional + nrest;
199 args = new Variable[max_arg];
201 for (int i = 0; i < max_arg; n = n.NextSibling)
202 args[i++] = domain.Defvar ((Symbol) n.Attributes[0].Value);
208 min_arg = max_arg = 0;
213 private static void parse_body (Domain domain, XmlNode node,
216 for (node = node.FirstChild; node != null; node = node.NextSibling)
217 if (node.Name != Qdescription
218 && node.Name != Qargs)
221 for (XmlNode n = node; n != null; n = n.NextSibling)
225 body = new Term[nterms];
226 for (nterms = 0; node != null; node = node.NextSibling, nterms++)
227 body[nterms] = new Term (domain, node);
233 internal class Macro : Function
235 internal Variable[] args;
236 internal Term[] body;
238 public Macro (Domain domain, XmlNode node)
240 parse_head (domain, node, out name, out min_arg, out max_arg,
244 public void SetBody (Domain domain, XmlNode node)
246 parse_body (domain, node, out body);
249 public override Term Call (Domain domain, Variable vari, Term[] args)
251 Bindings current = domain.bindings;
255 for (int i = 0; i < min_arg; i++)
256 domain.Bind (this.args[i], args[i]);
260 domain.Catch (CatchTag.Return);
261 foreach (Term term in body)
263 result = term.Eval (domain);
272 domain.UnboundTo (current);
278 internal class Lambda : Function
280 internal Variable[] args;
281 internal Term[] body;
283 public Lambda (Domain domain, XmlNode node)
285 parse_head (domain, node, out name, out min_arg, out max_arg,
289 public Lambda (Domain domain, Symbol name, Symbol[] args)
299 for (i = 0; i < args.Length; i++, nfixed++)
300 if (args[i] == Qoptional || args[i] == Qrest)
304 if (args[i] == Qoptional)
306 for (i++; i < args.Length; i++, noptional++)
307 if (args[i] == Qrest)
314 max_arg = nfixed + noptional + nrest;
315 this.args = new Variable[max_arg];
317 for (i = j = 0; j < this.args.Length; i++)
318 if (args[i] != Qoptional || args[i] != Qrest)
319 this.args[j++] = domain.Defvar (args[i]);
323 min_arg = max_arg = 0;
327 public void SetBody (Domain domain, XmlNode node)
329 parse_body (domain, node, out body);
332 public void SetBody (Term[] body)
337 public override Term Call (Domain domain, Variable vari, Term[] args)
339 Bindings current = domain.bindings;
346 Term[] newargs = new Term[args.Length];
347 for (i = 0; i < min_arg; i++)
348 newargs[i] = args[i].Eval (domain);
351 for (i = 0; i < min_arg; i++)
352 domain.Bind (this.args[i], args[i]);
356 domain.Catch (CatchTag.Return);
357 foreach (Term term in body)
359 result = term.Eval (domain);
368 domain.UnboundTo (current);
375 public class Variable
377 public Domain domain;
378 public readonly Symbol name;
381 public Variable (Domain domain, Symbol name, Term val)
383 this.domain = domain;
388 public virtual bool ValueP (Term val) { return true; }
390 public virtual Variable Clone (Domain domain)
392 return new Variable (domain, name, val);
395 public virtual void Reset () { val = Zero; }
397 public virtual string Description { get { return null; } }
403 if (! ValueP (value))
404 throw new Exception ("Invalid value: " + value);
409 public Term SetValue (int i)
416 public Term SetValue (string s)
422 public override string ToString () { return name + "(" + val + ")"; }
424 public abstract class Typed : Variable
426 protected string desc;
427 private Term default_val;
429 protected Typed (Domain domain, Symbol name, Term val, string desc)
430 : base (domain, name, val)
436 public override void Reset () { val = default_val; }
438 public override string Description { get { return desc; } }
441 public class Int : Typed
445 public bool IsSubrange (int[] r)
449 for (int i = 0; i < r.Length; i += 2)
452 for (j = 0; j < range.Length; j += 2)
453 if (range[j] <= r[i] && range[j + 1] >= r[i + 1])
455 if (j >= range.Length)
461 public Int (Domain domain, Symbol name, int n, string desc, int[] range)
462 : base (domain, name, new Term (n), desc)
464 if (range != null && range.Length % 2 == 1)
465 throw_exception ("Range length for {0} not even", name);
468 throw_exception ("Invalid integer value for {0}: {1}", name, val);
471 public override bool ValueP (Term term)
478 for (int i = 0; i < range.Length; i += 2)
479 if (range[i] <= n && range[i + 1] >= n)
484 public override Variable Clone (Domain domain)
486 return new Int (domain, name, val.Intval, desc, range);
489 public int[] Range { get { return range; } set { range = value; } }
492 public class Str : Typed
494 private string[] range;
496 public bool IsSubrange (string[] r)
500 for (int i = 0; i < r.Length; i++)
503 for (j = 0; j < range.Length; j++)
504 if (range[j] == r[i])
506 if (j >= range.Length)
512 public Str (Domain domain, Symbol name, string str, string desc,
514 : base (domain, name, new Term (str), desc)
518 throw_exception ("Invalid string value for {0}: {1}", name, val);
521 public override bool ValueP (Term term)
527 string str = term.Strval;
528 foreach (string s in range)
534 public override Variable Clone (Domain domain)
536 return new Str (domain, name, val.Strval, desc, range);
539 public string[] Range { get { return range; } set { range = value; } }
542 public class Sym : Typed
544 public Symbol[] range;
546 public bool IsSubrange (Symbol[] r)
550 for (int i = 0; i < r.Length; i++)
553 for (j = 0; j < range.Length; j++)
554 if (range[j] == r[i])
556 if (j >= range.Length)
562 public Sym (Domain domain, Symbol name, Symbol sym, string desc,
564 : base (domain, name, new Term (sym), desc)
568 throw_exception ("Invalid symbol value for {0}: {1}", name, val);
571 public override bool ValueP (Term term)
577 Symbol name = term.Symval;
578 foreach (Symbol n in range)
584 public override Variable Clone (Domain domain)
586 return new Sym (domain, name, val.Symval, desc, range);
589 public Symbol[] Range { get { return range; } set { range = value; } }
593 internal class Bindings
595 private Variable vari;
596 private Term old_value;
597 private Bindings next;
599 private Bindings (Variable vari)
602 old_value = vari.Value;
605 public static Bindings Bind (Bindings bindings, Variable vari, Term val)
607 Bindings b = new Bindings (vari);
614 internal Bindings UnboundTo (Bindings boundary)
616 for (Bindings b = this; b != boundary; b = b.next)
617 b.vari.Value = b.old_value;
621 public override string ToString ()
623 string str = "(bindings";
624 for (Bindings b = this; b != null; b = b.next)
625 str += " " + vari.name + "=" + b.old_value;
630 private static void throw_exception (string msg)
632 throw new Exception (msg);
635 private static void throw_exception (string fmt, params object[] args)
637 throw new Exception (String.Format (fmt, args));
640 internal class CatchTag : IEquatable<CatchTag>
644 public CatchTag (Symbol sym) { val = (string) sym; }
645 private CatchTag (int i) { val = i; }
647 public static CatchTag Return = new CatchTag (0);
648 public static CatchTag Break = new CatchTag (1);
650 public static bool operator== (CatchTag t1, CatchTag t2)
651 { return t1.val == t2.val; }
653 public static bool operator!= (CatchTag t1, CatchTag t2)
654 { return t1.val != t2.val; }
656 public bool Equals (CatchTag tag) { return this.val == tag.val; }
657 public override bool Equals (object val) { return this.val == val; }
659 public override int GetHashCode () { return val.GetHashCode (); }
665 public object context;
666 public int depth = 0;
668 internal Dictionary<Symbol, TermType> termtypes
669 = new Dictionary<Symbol, TermType> ();
670 internal Dictionary<Symbol, Function> functions
671 = new Dictionary<Symbol, Function> ();
672 internal Dictionary<Symbol, Variable> variables
673 = new Dictionary<Symbol, Variable> ();
674 internal Bindings bindings;
675 private Stack<CatchTag> catch_stack = new Stack<CatchTag> ();
676 private int catch_count = 0;
678 internal Domain (Symbol name) { this.name = name; }
680 public Domain (Symbol name, object context)
681 : this (name, basic, context) { }
683 public Domain (Symbol name, Domain parent, object context) : this (name)
685 termtypes = new Dictionary<Symbol, TermType> (parent.termtypes);
686 functions = new Dictionary<Symbol, Function> (parent.functions);
687 variables = new Dictionary<Symbol, Variable> (parent.variables);
688 this.context = context;
691 internal void Bind (Variable vari, Term value)
693 bindings = Bindings.Bind (bindings, vari, value);
696 internal void UnboundTo (Bindings boundary)
698 if (bindings != null)
699 bindings = bindings.UnboundTo (boundary);
702 internal void Catch (CatchTag tag)
704 catch_stack.Push (tag);
708 internal void Uncatch ()
711 if (catch_count > catch_stack.Count)
716 get { return catch_count < catch_stack.Count; }
719 internal void ThrowReturn ()
721 foreach (CatchTag tag in catch_stack)
724 if (tag == CatchTag.Return)
729 internal void ThrowBreak ()
731 if (catch_stack.Peek () != CatchTag.Break)
732 throw_exception ("No outer loop to break");
736 internal void ThrowTag (CatchTag tag)
738 foreach (CatchTag elt in catch_stack)
746 public void DefTerm (Symbol name, TermParser parser)
748 if (termtypes.ContainsKey (name)
749 || functions.ContainsKey (name))
750 throw new Exception ("already defined: " + name);
751 termtypes[name] = new TermType (name, parser);
754 public void DefSubr (Builtin builtin, string str, bool setvar,
755 int min_arg, int max_arg, params string[] aliases)
758 if (termtypes.ContainsKey (name))
759 throw new Exception ("already defined as termtype: " + name);
760 Function func = new Function.Subroutine (builtin, name, setvar,
762 functions[name] = func;
763 foreach (string a in aliases)
764 functions[(Symbol) a] = func;
767 public void DefSpecial (Builtin builtin, string str,
768 int min_arg, int max_arg,
769 params string[] aliases)
772 if (termtypes.ContainsKey (name))
773 throw new Exception ("already defined as termtype: " + name);
774 Function func = new Function.SpecialForm (builtin, name,
776 functions[name] = func;
777 foreach (string a in aliases)
778 functions[(Symbol) a] = func;
781 public void DefAlias (string alias, string str)
783 functions[(Symbol) alias] = functions[(Symbol) str];
786 public void Defun (Symbol name, Symbol[] args, Term[] body,
791 if (termtypes.ContainsKey (name))
792 throw new Exception ("already defined as termtype: " + name);
793 if (prototype || ! functions.TryGetValue (name, out func))
795 func = new Function.Lambda (this, name, args);
796 functions[name] = func;
799 ((Function.Lambda) func).SetBody (body);
802 public void Defun (XmlNode node, bool prototype)
804 Symbol name = node.Attributes[Qfname].Value;
805 if (termtypes.ContainsKey (name))
806 throw new Exception ("already defined as termtype: " + name);
809 if (prototype || ! functions.TryGetValue (name, out func))
811 func = new Function.Lambda (this, node);
812 functions[name] = func;
815 ((Function.Lambda) func).SetBody (this, node);
818 public void Defun (Function func)
820 functions[func.name] = func;
823 public void Defmacro (XmlNode node, bool prototype)
825 Symbol name = node.Attributes[Qfname].Value;
826 if (termtypes.ContainsKey (name))
827 throw new Exception ("already defined as termtype: " + name);
830 if (prototype || ! functions.TryGetValue (name, out func))
832 func = new Function.Macro (this, node);
833 functions[name] = func;
836 ((Function.Macro) func).SetBody (this, node);
839 public Variable Defvar (XmlNode node)
841 Symbol name = node.Attributes[0].Value;
845 node = node.FirstChild;
846 if (node != null && node.Name == Qdescription)
848 desc = node.InnerText;
849 node = node.NextSibling;
855 Symbol type = node.Name;
856 XmlNodeList range_list = null;
858 string val = node.InnerText;
860 node = node.NextSibling;
863 range_list = node.ChildNodes;
864 nranges = range_list.Count;
867 if (type == Qinteger)
869 int n = parse_integer (val);
871 if (range_list != null)
873 range = new int[nranges * 2];
874 for (int i = 0; i < nranges; i++)
876 XmlNode nd = range_list[i];
877 if (nd.Name == Qrange)
880 = parse_integer (nd.FirstChild.InnerText);
882 = parse_integer (nd.LastChild.InnerText);
888 = parse_integer (nd.FirstChild.InnerText);
892 vari = DefvarInt (name, n, desc, range);
894 else if (type == Qstring)
896 string[] range = null;
897 if (range_list != null)
899 range = new string[nranges];
900 for (int i = 0; i < nranges; i++)
901 range[i] = range_list[i].FirstChild.InnerText;
903 vari = DefvarStr (name, val, desc, range);
905 else if (type == Qsymbol)
907 Symbol[] range = null;
908 if (range_list != null)
910 range = new Symbol[nranges];
911 for (int i = 0; i < nranges; i++)
912 range[i] = range_list[i].FirstChild.InnerText;
914 vari = DefvarSym (name, (Symbol) val, desc, range);
917 throw new Exception ("Unknown type: " + type);
921 if (variables.TryGetValue (name, out vari))
922 vari = vari.Clone (this);
924 vari = new Variable (this, name, Zero);
925 variables[name] = vari;
927 Console.WriteLine (vari);
931 public Variable Defvar (Variable vari)
933 vari = vari.Clone (this);
934 variables[vari.name] = vari;
938 internal Variable Defvar (Symbol name)
940 Variable vari = new Variable (this, name, Zero);
941 variables[name] = vari;
945 public Variable DefvarInt (Symbol name, int n, string desc, int[] range)
949 if (variables.TryGetValue (name, out vari))
951 Variable.Int intvari = vari as Variable.Int;
953 throw new Exception ("Variable type mismatch: " + name);
955 range = intvari.Range;
956 else if (! intvari.IsSubrange (range))
957 throw new Exception ("Variable range mismatch: " + name);
959 desc = vari.Description;
961 vari = new Variable.Int (this, name, n, desc, range);
962 variables[name] = vari;
966 public Variable DefvarStr (Symbol name, string str, string desc,
971 if (variables.TryGetValue (name, out vari))
973 Variable.Str strvari = vari as Variable.Str;
975 throw new Exception ("Variable type mismatch: " + name);
977 range = strvari.Range;
978 else if (! strvari.IsSubrange (range))
979 throw new Exception ("Variable range mismatch: " + name);
981 desc = vari.Description;
983 vari = new Variable.Str (this, name, str, desc, range);
984 variables[name] = vari;
988 public Variable DefvarSym (Symbol name, Symbol sym, string desc,
993 if (variables.TryGetValue (name, out vari))
995 Variable.Sym symvari = vari as Variable.Sym;
997 throw new Exception ("Variable type mismatch: " + name);
999 range = symvari.Range;
1000 else if (! symvari.IsSubrange (range))
1001 throw new Exception ("Variable range mismatch: " + name);
1003 desc = vari.Description;
1005 vari = new Variable.Sym (this, name, sym, desc, range);
1006 variables[name] = vari;
1010 internal Function GetFunc (Symbol name)
1014 if (! functions.TryGetValue (name, out func))
1015 throw new Exception ("Unknown function: " + name);
1019 public bool CopyFunc (Domain domain, Symbol name)
1021 Function func = GetFunc (name);
1023 domain.functions[name] = func;
1027 public void CopyFunc (Domain domain)
1029 foreach (KeyValuePair<Symbol, Function> kv in functions)
1030 domain.functions[kv.Key] = kv.Value;
1033 public Variable GetVar (Symbol name, bool create)
1037 if (! variables.TryGetValue (name, out vari))
1041 variables[name] = vari = new Variable (this, name, Zero);
1046 public override string ToString ()
1048 string str = "<(functions";
1049 foreach (KeyValuePair<Symbol, Function> kv in functions)
1050 str += " " + kv.Key;
1051 str += ") (variabls";
1052 foreach (KeyValuePair<Symbol, Variable> kv in variables)
1053 str += " " + kv.Value;
1055 if (bindings != null)
1056 str += " " + bindings;
1057 if (context != null)
1058 str += " (" + context + ")";
1063 internal void DebugWrite (bool head, string fmt, params string[] arg)
1065 if (debug_depth > depth)
1069 Console.WriteLine ();
1070 for (int i = 0; i < depth; i++)
1071 Console.Write (" ");
1073 Console.Write (fmt, arg);
1077 public object SaveValues ()
1079 Dictionary<Variable,Term> values = new Dictionary<Variable,Term> ();
1081 foreach (KeyValuePair<Symbol,Variable> kv in variables)
1082 values[kv.Value] = kv.Value.Value.Clone ();
1086 public void RestoreValues (object values)
1088 foreach (KeyValuePair<Variable,Term> kv
1089 in (Dictionary<Variable,Term>) values)
1090 kv.Key.Value = kv.Value;
1094 public delegate Term Builtin (Domain domain, Variable vari, Term[] args);
1096 private static Domain basic = new Domain ("basic");
1098 static Xexpression ()
1100 basic.DefTerm ("funcall", Funcall.parser);
1101 basic.DefTerm ("varref", Varref.parser);
1103 basic.DefSubr (Fset, "set", true, 1, 1, "=");
1104 basic.DefSubr (Fnot, "not", false, 1, 1, "!");
1105 basic.DefSubr (Fadd, "add", true, 1, -1, "+");
1106 basic.DefSubr (Fmul, "mul", true, 1, -1, "*");
1107 basic.DefSubr (Fsub, "sub", true, 1, -1, "-");
1108 basic.DefSubr (Fdiv, "div", true, 1, -1, "/");
1109 basic.DefSubr (Fmod, "mod", true, 1, 2, "%");
1110 basic.DefSubr (Flogior, "logior", true, 1, -1, "|");
1111 basic.DefSubr (Flogand, "logand", true, 1, -1, "&");
1112 basic.DefSubr (Flsh, "lsh", true, 1, 2, "<<");
1113 basic.DefSubr (Frsh, "rsh", true, 1, 2, ">>");
1114 basic.DefSubr (Feq, "eq", false, 2, -1, "==");
1115 basic.DefSubr (Fnoteq, "noteq", false, 2, 2, "!=");
1116 basic.DefSubr (Flt, "lt", false, 2, -1, "<");
1117 basic.DefSubr (Fle, "le", false, 2, -1, "<=");
1118 basic.DefSubr (Fgt, "gt", false, 2, -1, ">");
1119 basic.DefSubr (Fge, "ge", false, 2, -1, ">=");
1120 basic.DefSubr (Fappend, "append", true, 0, -1);
1121 basic.DefSubr (Fconcat, "concat", true, 0, -1);
1122 basic.DefSubr (Fnth, "nth", false, 2, 2);
1123 basic.DefSubr (Fcopy, "copy", false, 1, 1);
1124 basic.DefSubr (Fins, "ins", true, 2, 2);
1125 basic.DefSubr (Fdel, "del", true, 2, 2);
1126 basic.DefSubr (Feval, "eval", false, 1, 1);
1127 basic.DefSubr (Fbreak, "break", false, 0, 1);
1128 basic.DefSubr (Freturn, "return", false, 0, 1);
1130 basic.DefSpecial (Fand, "and", 1, -1, "&&");
1131 basic.DefSpecial (For, "or", 1, -1, "||");
1132 basic.DefSpecial (Fprogn, "progn", 0, -1, "expr");
1133 basic.DefSpecial (Fif, "if", 2, 3);
1134 basic.DefSpecial (Fwhen, "when", 1, -1);
1135 basic.DefSpecial (Floop, "loop", 1, -1);
1136 basic.DefSpecial (Fwhile, "while", 1, -1);
1137 basic.DefSpecial (Fcond, "cond", 1, -1);
1138 basic.DefSpecial (Fforeach, "foreach", 2, -1);
1139 basic.DefSpecial (Fquote, "quote", 1, 1);
1140 basic.DefSpecial (Ftype, "type", 1, 1);
1141 basic.DefSpecial (Fcatch, "catch", 2, 2);
1142 basic.DefSpecial (Fthrow, "throw", 1, 2);
1145 private static Term Fset (Domain domain, Variable vari, Term[] args)
1147 vari.Value = args[0];
1151 private static Term Fnot (Domain domain, Variable vari, Term[] args)
1153 return args[0].IsTrue ? Zero : One;
1156 private static Term Fadd (Domain domain, Variable vari, Term[] args)
1158 int n = vari == null ? 0 : vari.Value.Intval;
1160 foreach (Term arg in args)
1162 return (vari == null ? new Term (n) : vari.SetValue (n));
1165 private static Term Fmul (Domain domain, Variable vari, Term[] args)
1167 int n = vari == null ? 1 : vari.Value.Intval;
1168 foreach (Term arg in args)
1170 return (vari == null ? new Term (n) : vari.SetValue (n));
1173 private static Term Fsub (Domain domain, Variable vari, Term[] args)
1184 n = vari.Value.Intval;
1187 while (i < args.Length)
1188 n -= args[i++].Intval;
1189 return (vari == null ? new Term (n) : vari.SetValue (n));
1192 private static Term Fdiv (Domain domain, Variable vari, Term[] args)
1203 n = vari.Value.Intval;
1206 while (i < args.Length)
1207 n /= args[i++].Intval;
1208 return (vari == null ? new Term (n) : vari.SetValue (n));
1211 private static Term Fmod (Domain domain, Variable vari, Term[] args)
1213 int n = args[0].Intval % args[1].Intval;
1215 return (vari == null ? new Term (n) : vari.SetValue (n));
1218 private static Term Flogior (Domain domain, Variable vari, Term[] args)
1220 int n = vari == null ? 0 : vari.Value.Intval;
1221 foreach (Term arg in args)
1223 return (vari == null ? new Term (n) : vari.SetValue (n));
1226 private static Term Flogand (Domain domain, Variable vari, Term[] args)
1237 n = vari.Value.Intval;
1240 while (i < args.Length)
1241 n &= args[i++].Intval;
1242 return (vari == null ? new Term (n) : vari.SetValue (n));
1245 private static Term Flsh (Domain domain, Variable vari, Term[] args)
1247 int n = args[0].Intval << args[1].Intval;
1248 return (vari == null ? new Term (n) : vari.SetValue (n));
1251 private static Term Frsh (Domain domain, Variable vari, Term[] args)
1253 int n = args[0].Intval >> args[1].Intval;
1254 return (vari == null ? new Term (n) : vari.SetValue (n));
1257 private static Term Feq (Domain domain, Variable vari, Term[] args)
1261 if (o.objval == null)
1263 for (int i = 1; i < args.Length; i++)
1264 if (args[i].objval != null || args[i].intval != o.intval)
1269 for (int i = 1; i < args.Length; i++)
1270 if (o.objval.Equals (args[i].objval))
1276 private static Term Fnoteq (Domain domain, Variable vari, Term[] args)
1278 return Feq (domain, vari, args);
1281 private static Term Flt (Domain domain, Variable vari, Term[] args)
1283 int n = args[0].Intval;
1285 for (int i = 1; i < args.Length; i++)
1287 int n1 = args[i].Intval;
1295 private static Term Fle (Domain domain, Variable vari, Term[] args)
1297 int n = args[0].Intval;
1298 for (int i = 1; i < args.Length; i++)
1300 int n1 = args[i].Intval;
1308 private static Term Fgt (Domain domain, Variable vari, Term[] args)
1310 int n = args[0].Intval;
1311 for (int i = 1; i < args.Length; i++)
1313 int n1 = args[i].Intval;
1321 private static Term Fge (Domain domain, Variable vari, Term[] args)
1323 int n = args[0].Intval;
1324 for (int i = 1; i < args.Length; i++)
1326 int n1 = args[i].Intval;
1334 private static Term Fappend (Domain domain, Variable vari, Term[] args)
1339 list = new List<Term> ();
1341 list = vari.Value.Listval;
1343 foreach (Term arg in args)
1346 list.AddRange ((List<Term>) arg.objval);
1354 result.objval = list;
1360 private static Term Fconcat (Domain domain, Variable vari, Term[] args)
1367 str = vari.Value.Strval;
1369 foreach (Term arg in args)
1372 str += (string) arg.objval;
1373 else if (arg.IsList)
1374 foreach (Term term in (List<Term>) arg.objval)
1375 str += (char) term.Intval;
1377 str += (char) arg.Intval;
1387 return vari.SetValue (str);
1390 private static Term Fnth (Domain domain, Variable vari, Term[] args)
1396 result.intval = ((string) args[1].objval)[args[0].Intval];
1397 result.objval = null;
1399 else if (args[1].IsList)
1401 result = ((List<Term>) args[1].objval)[args[0].Intval];
1404 throw new Exception ("Term is not enumelable: " + args[1]);
1408 private static Term Fcopy (Domain domain, Variable vari, Term[] args)
1413 result.objval = new List<Term> (args[0].Listval);
1417 private static Term Fins (Domain domain, Variable vari, Term[] args)
1419 Term term = vari.Value;
1423 string str = term.Strval.Insert (args[0].Intval, args[1].Strval);
1424 vari.SetValue (str);
1426 else if (vari.Value.IsList)
1427 vari.Value.Listval.InsertRange (args[0].Intval, args[1].Listval);
1429 throw new Exception ("term is not collection: " + vari.Value);
1433 private static Term Fdel (Domain domain, Variable vari, Term[] args)
1435 if (vari.Value.IsStr)
1438 = vari.Value.Strval.Remove (args[0].Intval,
1439 args[1].Intval - args[0].Intval);
1440 vari.SetValue (str);
1442 else if (vari.Value.IsList)
1443 vari.Value.Listval.RemoveRange (args[0].Intval,
1444 args[1].Intval - args[0].Intval);
1446 throw new Exception ("term is not collection: " + vari.Value);
1450 private static Term Fand (Domain domain, Variable vari, Term[] args)
1452 foreach (Term arg in args)
1453 if (! arg.Eval (domain).IsTrue)
1458 private static Term For (Domain domain, Variable vari, Term[] args)
1460 foreach (Term arg in args)
1461 if (arg.Eval (domain).IsTrue)
1466 private static Term Feval (Domain domain, Variable vari, Term[] args)
1468 return (args[0].Eval (domain));
1471 private static Term Fprogn (Domain domain, Variable vari, Term[] args)
1475 foreach (Term arg in args)
1476 result = arg.Eval (domain);
1480 private static Term Fif (Domain domain, Variable vari, Term[] args)
1482 if (args[0].Eval (domain).IsTrue)
1483 return args[1].Eval (domain);
1484 if (args.Length == 2)
1486 return args[2].Eval (domain);
1489 private static Term Fwhen (Domain domain, Variable vari, Term[] args)
1491 if (! args[0].Eval (domain).IsTrue)
1494 for (int i = 1; i < args.Length; i++)
1495 result = args[i].Eval (domain);
1499 private static Term Freturn (Domain domain, Variable vari, Term[] args)
1501 domain.ThrowReturn ();
1502 return args.Length == 0 ? Zero : args[0];
1505 private static Term Fbreak (Domain domain, Variable vari, Term[] args)
1507 domain.ThrowBreak ();
1508 return args.Length == 0 ? Zero : args[0];
1511 private static Term Floop (Domain domain, Variable vari, Term[] args)
1515 domain.Catch (CatchTag.Break);
1516 while (! domain.Thrown)
1517 foreach (Term arg in args)
1519 result = arg.Eval (domain);
1529 private static Term Fwhile (Domain domain, Variable vari, Term[] args)
1533 domain.Catch (CatchTag.Break);
1534 while (! domain.Thrown && args[0].Eval (domain).IsTrue)
1535 for (int i = 1; i < args.Length; i++)
1537 result = args[i].Eval (domain);
1547 private static Term Fcond (Domain domain, Variable vari, Term[] args)
1549 foreach (Term arg in args)
1551 List<Term> list = arg.Listval;
1552 Term result = list[0].Eval (domain);
1556 for (int i = 1; i < list.Count; i++)
1557 result = list[i].Eval (domain);
1564 private static Term Fforeach (Domain domain, Variable vari,
1567 Term result = args[0].Eval (domain);
1570 List<Term> list = result.Listval;
1571 Bindings current = domain.bindings;
1574 domain.Catch (CatchTag.Break);
1575 foreach (Term term in list)
1577 domain.Bind (vari, term);
1579 for (int i = 1; i < args.Length; i++)
1581 result = args[i].Eval (domain);
1586 domain.UnboundTo (current);
1595 private static Term Fquote (Domain domain, Variable vari, Term[] args)
1597 return new Term (args[0]);
1600 private static Term Ftype (Domain domain, Variable vari, Term[] args)
1606 if (args[0].IsSymbol)
1613 public static Term Fcatch (Domain domain, Variable vari, Term[] args)
1617 domain.Catch (new CatchTag (args[0].Symval));
1618 result = args[1].Eval (domain);
1625 public static Term Fthrow (Domain domain, Variable vari, Term[] args)
1627 domain.ThrowTag (new CatchTag (args[0].Symval));
1628 return (args.Length == 1 ? Zero : args[1]);
1631 public delegate TermValue TermParser (Domain domain, XmlNode node);
1633 public class TermType
1635 public readonly Symbol type;
1636 internal readonly TermParser parser;
1638 public TermType (Symbol type, TermParser parser)
1641 this.parser = parser;
1645 public abstract class TermValue
1647 public virtual Term Eval (Domain domain) { return new Term (this); }
1648 public virtual TermValue Clone () { return this; }
1651 private class Varref : TermValue
1653 private Symbol name;
1654 private Variable vari;
1656 public Varref (Symbol name) { this.name = name; }
1658 public override Term Eval (Domain domain)
1660 if (vari == null || vari.domain != domain)
1661 vari = domain.GetVar (name, true);
1665 internal static TermValue parser (Domain domain, XmlNode node)
1667 return new Varref ((Symbol) node.Attributes[Qvname].Value);
1670 public override string ToString ()
1672 return "<varref vname=\"" + name + "\"/>";
1676 private class Funcall : TermValue
1678 internal Function func;
1679 internal Variable vari;
1680 internal Term[] args;
1682 public Funcall (Function func, Variable vari, Term[] args)
1686 int nargs = args.Length;
1687 if (nargs < func.min_arg
1688 || (func.max_arg >= 0 && nargs > func.max_arg))
1689 throw_exception ("Invalid number of arguments to {0}: ",
1697 internal static TermValue parser (Domain domain, XmlNode node)
1699 Symbol fname = node.Name;
1702 if (fname == Qfuncall)
1703 fname = node.Attributes[Qfname].Value;
1704 Function func = domain.GetFunc (fname);
1706 attr = node.Attributes[Qvname];
1707 vari = attr == null ? null : domain.GetVar (attr.Value, true);
1708 XmlNodeList nlist = node.ChildNodes;
1709 int nargs = nlist.Count;
1710 Term[] args = new Term[nargs];
1711 for (int i = 0; i < nargs; i++)
1712 args[i] = new Term (domain, nlist[i]);
1713 return new Funcall (func, vari, args);
1716 public override Term Eval (Domain domain)
1718 domain.DebugWrite (true, ToString ());
1720 Term result = func.Call (domain, vari, args);
1722 domain.DebugWrite (true, " ==> {0}", result.ToString ());
1726 public override TermValue Clone ()
1728 return new Funcall (func, vari, args);
1731 public override string ToString ()
1733 string str = "<" + func.name;
1735 str += " vname=\"" + vari.name + "\"";
1739 if (func is Function.SpecialForm)
1740 str += String.Format ("({0})...", args.Length);
1742 foreach (Term e in args)
1744 return (str + "</" + func.name + ">");
1751 public object objval;
1753 // <integer>...</integer>
1754 public Term (int i) { intval = i; objval = null; }
1755 // <symbol>...</symbol>
1756 public Term (Symbol name) { intval = 0; objval = name; }
1757 // <string>...</string>
1758 public Term (string str) { intval = 0; objval = str; }
1760 public Term (List<Term> list) { intval = 0; objval = list; }
1762 public Term (Term term) { intval = term.intval; objval = term.objval; }
1763 public Term (TermValue obj) { intval = 0; objval = obj; }
1765 public Term (Domain domain, XmlNode node)
1767 Symbol name = node.Name;
1769 if (name == Qinteger)
1771 intval = parse_integer (node.InnerText);
1777 if (name == Qsymbol)
1778 objval = (Symbol) node.InnerText;
1779 else if (name == Qstring)
1780 objval = node.InnerText.Clone ();
1781 else if (name == Qlist)
1783 List<Term> list = new List<Term> ();
1784 for (node = node.FirstChild; node != null;
1785 node = node.NextSibling)
1786 list.Add (new Term (domain, node));
1793 if (domain.termtypes.TryGetValue (name, out term_type))
1794 objval = term_type.parser (domain, node);
1797 Funcall funcall = (Funcall) Funcall.parser (domain, node);
1798 if (funcall.func is Function.Macro)
1800 Term result = funcall.Eval (domain);
1801 intval = result.intval;
1802 objval = result.objval;
1811 // <varref vname="VNAME"/>
1812 public Term (Domain domain, Symbol vname)
1815 objval = new Varref (vname);
1818 // <funcall fname="FNAME">...</funcall>
1819 public Term (Domain domain, Symbol fname, Term[] args)
1820 : this (domain, fname, Qnull, args) { }
1822 // <funcall fname="FNAME" vname="VNAME">...</funcall>
1823 public Term (Domain domain, Symbol fname, Symbol vname, Term[] args)
1827 Function func = domain.GetFunc (fname);
1828 Variable vari = vname == Qnull ? null : domain.GetVar (vname, true);
1829 Funcall funcall = new Funcall (func, vari, args);
1830 if (func is Function.Macro)
1832 Term result = funcall.Eval (domain);
1833 intval = result.intval;
1834 objval = result.objval;
1840 public object Objval {
1843 throw new Exception ("term is an integer: " + this);
1851 throw new Exception ("term is not integer: " + this);
1856 public string Strval {
1859 throw new Exception ("term is not string: " + this);
1860 return (string) objval;
1864 public string Symval {
1867 throw new Exception ("term is not symbol: " + this);
1868 return (Symbol) objval;
1872 public List<Term> Listval {
1875 throw new Exception ("term is not list: " + this);
1876 return (List<Term>) objval;
1880 public bool IsTrue {
1882 return (objval == null
1884 : objval is List<Term>
1885 ? (((List<Term>) objval).Count != 0)
1889 public bool IsInt { get { return (objval == null); } }
1890 public bool IsStr { get { return (objval is string); } }
1891 public bool IsSymbol { get { return (objval is Symbol); } }
1892 public bool IsList { get { return (objval is List<Term>); } }
1894 public bool IsType (Type type)
1896 return (objval == null ? type == typeof (int)
1897 : type == objval.GetType ());
1900 public Term Eval (Domain domain)
1902 if (objval == null || objval is Symbol || objval is string)
1904 if (objval is List<Term>)
1905 return new Term ((List<Term>) objval);
1906 return ((TermValue) objval).Eval (domain);
1909 public Term Clone ()
1911 if (objval == null || objval is Symbol || objval is string)
1913 if (objval is List<Term>)
1915 List<Term> list = new List<Term> ();
1916 list.InsertRange (0, ((List<Term>) objval));
1917 return new Term (list);
1919 return new Term (((TermValue) objval).Clone ());
1922 public override string ToString ()
1927 str = "<integer>" + intval + "</integer>";
1928 else if (objval is Symbol)
1929 str = "<symbol>" + objval + "</symbol>";
1930 else if (objval is string)
1931 str = "<string>" + objval + "</string>";
1932 else if (objval is List<Term>)
1935 foreach (Term e in (List<Term>) objval)
1939 else if (objval is Term)
1940 str = "<quote>" + objval + "</quote>";
1941 else if (objval is TermValue)
1942 str = ((TermValue) objval).ToString ();
1944 throw new Exception ("invalid Term object: " + objval);
1949 static private Term Zero = new Term (0);
1950 static private Term One = new Term (1);
1951 static private Term TermInt = new Term (Qinteger);
1952 static private Term TermStr = new Term (Qstring);
1953 static private Term TermSymbol = new Term (Qsymbol);
1954 static private Term TermList = new Term (Qlist);
1955 static private Term TermTerm = new Term ((Symbol) "term");
1957 internal static int parse_integer (string str)
1959 int len = str.Length;
1960 bool negative = false;
1963 return (len == 0 ? 0 : str[0] - '0');
1970 if ((c == '0' || c == '#') && str[1] == 'x')
1973 for (int idx = 2; idx < len; idx++)
1979 i = i * 16 + (c - '0');
1983 i = i * 16 + (c - 'A');
1987 i = i * 16 + (c - 'a');
1996 for (int idx = 1; idx < len; idx++)
1999 if (c < '0' || c > '9')
2001 i = i * 10 + (c - '0');
2003 return negative ? - i : i;
2006 private Term[] terms;
2008 public static Term[] ParseTerms (Domain domain, XmlNode node)
2011 for (XmlNode n = node; n != null; n = n.NextSibling)
2012 if (n.NodeType == XmlNodeType.Element)
2014 if (n.Name == Qdefun)
2015 domain.Defun (n, true);
2016 else if (n.Name == Qdefmacro)
2017 domain.Defmacro (n, true);
2018 else if (n.Name == Qdefvar)
2023 Term[] terms = new Term[nterms];
2025 for (XmlNode n = node; n != null; n = n.NextSibling)
2026 if (n.NodeType == XmlNodeType.Element)
2028 if (n.Name == Qdefun)
2029 domain.Defun (n, false);
2030 else if (n.Name == Qdefmacro)
2031 domain.Defmacro (n, false);
2032 else if (n.Name != Qdefvar)
2033 terms[i++]= new Term (domain, n);
2038 public static Term Eval (Domain domain, Term[] terms)
2040 Term result = new Term (0);
2041 foreach (Term term in terms)
2044 if (result.Objval is Funcall)
2045 while ((result = result.Eval (domain)).Objval is Funcall);
2051 public Xexpression (Domain domain, XmlNode node)
2053 terms = ParseTerms (domain, node);
2056 public Xexpression (Domain domain, string url)
2058 XmlDocument doc = new XmlDocument (Symbol.NameTable);
2061 using (XmlTextReader reader = new XmlTextReader (url, doc.NameTable))
2065 } while (reader.NodeType != XmlNodeType.None
2066 && (reader.NodeType != XmlNodeType.Element
2067 || reader.Name != Qexpr));
2068 if (reader.NodeType == XmlNodeType.None)
2069 throw new Exception ("Node <expr> not found");
2070 node = doc.ReadNode (reader);
2072 terms = ParseTerms (domain, node.FirstChild);
2075 public Term Eval (Domain domain)
2081 domain.Catch (CatchTag.Return);
2082 foreach (Term term in terms)
2084 result = term.Eval (domain);
2094 public override string ToString ()
2097 for (int i = 0; i < terms.Length; i++)