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; }
401 if (! ValueP (value))
402 throw new Exception ("Invalid value: " + value);
407 public Term SetValue (int i)
414 public Term SetValue (string s)
420 public override string ToString () { return name + "(" + val + ")"; }
422 public abstract class Typed : Variable
424 protected string desc;
425 private Term default_val;
427 protected Typed (Domain domain, Symbol name, Term val, string desc)
428 : base (domain, name, val)
434 public override void Reset () { val = default_val; }
436 public string Description {
438 set { desc = value; }
442 public class Int : Typed
446 public bool IsSubrange (int[] r)
450 for (int i = 0; i < r.Length; i += 2)
453 for (j = 0; j < range.Length; j += 2)
454 if (range[j] <= r[i] && range[j + 1] >= r[i + 1])
456 if (j >= range.Length)
462 public Int (Domain domain, Symbol name, int n, string desc, int[] range)
463 : base (domain, name, new Term (n), desc)
465 if (range != null && range.Length % 2 == 1)
466 throw_exception ("Range length for {0} not even", name);
469 throw_exception ("Invalid integer value for {0}: {1}", name, val);
472 public override bool ValueP (Term term)
479 for (int i = 0; i < range.Length; i += 2)
480 if (range[i] <= n && range[i + 1] >= n)
485 public override Variable Clone (Domain domain)
487 return new Int (domain, name, val.Intval, desc, range);
490 public int[] Range { get { return range; } set { range = value; } }
493 public class Str : Typed
495 private string[] range;
497 public bool IsSubrange (string[] r)
501 for (int i = 0; i < r.Length; i++)
504 for (j = 0; j < range.Length; j++)
505 if (range[j] == r[i])
507 if (j >= range.Length)
513 public Str (Domain domain, Symbol name, string str, string desc,
515 : base (domain, name, new Term (str), desc)
519 throw_exception ("Invalid string value for {0}: {1}", name, val);
522 public override bool ValueP (Term term)
528 string str = term.Strval;
529 foreach (string s in range)
535 public override Variable Clone (Domain domain)
537 return new Str (domain, name, val.Strval, desc, range);
540 public string[] Range { get { return range; } set { range = value; } }
543 public class Sym : Typed
545 public Symbol[] range;
547 public bool IsSubrange (Symbol[] r)
551 for (int i = 0; i < r.Length; i++)
554 for (j = 0; j < range.Length; j++)
555 if (range[j] == r[i])
557 if (j >= range.Length)
563 public Sym (Domain domain, Symbol name, Symbol sym, string desc,
565 : base (domain, name, new Term (sym), desc)
569 throw_exception ("Invalid symbol value for {0}: {1}", name, val);
572 public override bool ValueP (Term term)
578 Symbol name = term.Symval;
579 foreach (Symbol n in range)
585 public override Variable Clone (Domain domain)
587 return new Sym (domain, name, val.Symval, desc, range);
590 public Symbol[] Range { get { return range; } set { range = value; } }
594 internal class Bindings
596 private Variable vari;
597 private Term old_value;
598 private Bindings next;
600 private Bindings (Variable vari)
603 old_value = vari.Value;
606 public static Bindings Bind (Bindings bindings, Variable vari, Term val)
608 Bindings b = new Bindings (vari);
615 internal Bindings UnboundTo (Bindings boundary)
617 for (Bindings b = this; b != boundary; b = b.next)
618 b.vari.Value = b.old_value;
622 public override string ToString ()
624 string str = "(bindings";
625 for (Bindings b = this; b != null; b = b.next)
626 str += " " + vari.name + "=" + b.old_value;
631 private static void throw_exception (string msg)
633 throw new Exception (msg);
636 private static void throw_exception (string fmt, params object[] args)
638 throw new Exception (String.Format (fmt, args));
641 internal class CatchTag : IEquatable<CatchTag>
645 public CatchTag (Symbol sym) { val = (string) sym; }
646 private CatchTag (int i) { val = i; }
648 public static CatchTag Return = new CatchTag (0);
649 public static CatchTag Break = new CatchTag (1);
651 public static bool operator== (CatchTag t1, CatchTag t2)
652 { return t1.val == t2.val; }
654 public static bool operator!= (CatchTag t1, CatchTag t2)
655 { return t1.val != t2.val; }
657 public bool Equals (CatchTag tag) { return this.val == tag.val; }
658 public override bool Equals (object val) { return this.val == val; }
660 public override int GetHashCode () { return val.GetHashCode (); }
666 public object context;
667 public int depth = 0;
669 internal Dictionary<Symbol, TermType> termtypes
670 = new Dictionary<Symbol, TermType> ();
671 internal Dictionary<Symbol, Function> functions
672 = new Dictionary<Symbol, Function> ();
673 internal Dictionary<Symbol, Variable> variables
674 = new Dictionary<Symbol, Variable> ();
675 internal Bindings bindings;
676 private Stack<CatchTag> catch_stack = new Stack<CatchTag> ();
677 private int catch_count = 0;
679 internal Domain (Symbol name) { this.name = name; }
681 public Domain (Symbol name, object context)
682 : this (name, basic, context) { }
684 public Domain (Symbol name, Domain parent, object context) : this (name)
686 termtypes = new Dictionary<Symbol, TermType> (parent.termtypes);
687 functions = new Dictionary<Symbol, Function> (parent.functions);
688 variables = new Dictionary<Symbol, Variable> (parent.variables);
689 this.context = context;
692 internal void Bind (Variable vari, Term value)
694 bindings = Bindings.Bind (bindings, vari, value);
697 internal void UnboundTo (Bindings boundary)
699 if (bindings != null)
700 bindings = bindings.UnboundTo (boundary);
703 internal void Catch (CatchTag tag)
705 catch_stack.Push (tag);
709 internal void Uncatch ()
712 if (catch_count > catch_stack.Count)
717 get { return catch_count < catch_stack.Count; }
720 internal void ThrowReturn ()
722 foreach (CatchTag tag in catch_stack)
725 if (tag == CatchTag.Return)
730 internal void ThrowBreak ()
732 if (catch_stack.Peek () != CatchTag.Break)
733 throw_exception ("No outer loop to break");
737 internal void ThrowTag (CatchTag tag)
739 foreach (CatchTag elt in catch_stack)
747 public void DefTerm (Symbol name, TermParser parser)
749 if (termtypes.ContainsKey (name)
750 || functions.ContainsKey (name))
751 throw new Exception ("already defined: " + name);
752 termtypes[name] = new TermType (name, parser);
755 public void DefSubr (Builtin builtin, string str, bool setvar,
756 int min_arg, int max_arg, params string[] aliases)
759 if (termtypes.ContainsKey (name))
760 throw new Exception ("already defined as termtype: " + name);
761 Function func = new Function.Subroutine (builtin, name, setvar,
763 functions[name] = func;
764 foreach (string a in aliases)
765 functions[(Symbol) a] = func;
768 public void DefSpecial (Builtin builtin, string str,
769 int min_arg, int max_arg,
770 params string[] aliases)
773 if (termtypes.ContainsKey (name))
774 throw new Exception ("already defined as termtype: " + name);
775 Function func = new Function.SpecialForm (builtin, name,
777 functions[name] = func;
778 foreach (string a in aliases)
779 functions[(Symbol) a] = func;
782 public void DefAlias (string alias, string str)
784 functions[(Symbol) alias] = functions[(Symbol) str];
787 public void Defun (Symbol name, Symbol[] args, Term[] body,
792 if (termtypes.ContainsKey (name))
793 throw new Exception ("already defined as termtype: " + name);
794 if (prototype || ! functions.TryGetValue (name, out func))
796 func = new Function.Lambda (this, name, args);
797 functions[name] = func;
800 ((Function.Lambda) func).SetBody (body);
803 public void Defun (XmlNode node, bool prototype)
805 Symbol name = node.Attributes[Qfname].Value;
806 if (termtypes.ContainsKey (name))
807 throw new Exception ("already defined as termtype: " + name);
810 if (prototype || ! functions.TryGetValue (name, out func))
812 func = new Function.Lambda (this, node);
813 functions[name] = func;
816 ((Function.Lambda) func).SetBody (this, node);
819 public void Defun (Function func)
821 functions[func.name] = func;
824 public void Defmacro (XmlNode node, bool prototype)
826 Symbol name = node.Attributes[Qfname].Value;
827 if (termtypes.ContainsKey (name))
828 throw new Exception ("already defined as termtype: " + name);
831 if (prototype || ! functions.TryGetValue (name, out func))
833 func = new Function.Macro (this, node);
834 functions[name] = func;
837 ((Function.Macro) func).SetBody (this, node);
840 public Variable Defvar (XmlNode node)
842 Symbol name = node.Attributes[0].Value;
846 node = node.FirstChild;
847 if (node != null && node.Name == Qdescription)
849 desc = node.InnerText;
850 node = node.NextSibling;
856 Symbol type = node.Name;
857 XmlNodeList range_list = null;
859 string val = node.InnerText;
861 node = node.NextSibling;
864 range_list = node.ChildNodes;
865 nranges = range_list.Count;
868 if (type == Qinteger)
870 int n = parse_integer (val);
872 if (range_list != null)
874 range = new int[nranges * 2];
875 for (int i = 0; i < nranges; i++)
877 XmlNode nd = range_list[i];
878 if (nd.Name == Qrange)
881 = parse_integer (nd.FirstChild.InnerText);
883 = parse_integer (nd.LastChild.InnerText);
889 = parse_integer (nd.FirstChild.InnerText);
893 vari = DefvarInt (name, n, desc, range);
895 else if (type == Qstring)
897 string[] range = null;
898 if (range_list != null)
900 range = new string[nranges];
901 for (int i = 0; i < nranges; i++)
902 range[i] = range_list[i].FirstChild.InnerText;
904 vari = DefvarStr (name, val, desc, range);
906 else if (type == Qsymbol)
908 Symbol[] range = null;
909 if (range_list != null)
911 range = new Symbol[nranges];
912 for (int i = 0; i < nranges; i++)
913 range[i] = range_list[i].FirstChild.InnerText;
915 vari = DefvarSym (name, (Symbol) val, desc, range);
918 throw new Exception ("Unknown type: " + type);
922 if (variables.TryGetValue (name, out vari))
923 vari = vari.Clone (this);
925 vari = new Variable (this, name, Zero);
926 variables[name] = 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);
956 if (! intvari.IsSubrange (range))
957 throw new Exception ("Variable range mismatch: " + name);
958 intvari.Range = range;;
961 intvari.Description = desc;
965 vari = new Variable.Int (this, name, n, desc, range);
966 variables[name] = vari;
971 public Variable DefvarStr (Symbol name, string str, string desc,
976 if (variables.TryGetValue (name, out vari))
978 Variable.Str strvari = vari as Variable.Str;
980 throw new Exception ("Variable type mismatch: " + name);
983 if (! strvari.IsSubrange (range))
984 throw new Exception ("Variable range mismatch: " + name);
985 strvari.Range = range;
988 strvari.Description = desc;
992 vari = new Variable.Str (this, name, str, desc, range);
993 variables[name] = vari;
998 public Variable DefvarSym (Symbol name, Symbol sym, string desc,
1003 if (variables.TryGetValue (name, out vari))
1005 Variable.Sym symvari = vari as Variable.Sym;
1006 if (symvari == null)
1007 throw new Exception ("Variable type mismatch: " + name);
1010 if (! symvari.IsSubrange (range))
1011 throw new Exception ("Variable range mismatch: " + name);
1012 symvari.Range = range;
1015 symvari.Description = desc;
1019 vari = new Variable.Sym (this, name, sym, desc, range);
1020 variables[name] = vari;
1025 internal Function GetFunc (Symbol name)
1029 if (! functions.TryGetValue (name, out func))
1030 throw new Exception ("Unknown function: " + name);
1034 public bool CopyFunc (Domain domain, Symbol name)
1036 Function func = GetFunc (name);
1038 domain.functions[name] = func;
1042 public void CopyFunc (Domain domain)
1044 foreach (KeyValuePair<Symbol, Function> kv in functions)
1045 domain.functions[kv.Key] = kv.Value;
1048 public Variable GetVar (Symbol name, bool create)
1052 if (! variables.TryGetValue (name, out vari))
1056 variables[name] = vari = new Variable (this, name, Zero);
1061 public override string ToString ()
1063 string str = "<(functions";
1064 foreach (KeyValuePair<Symbol, Function> kv in functions)
1065 str += " " + kv.Key;
1066 str += ") (variabls";
1067 foreach (KeyValuePair<Symbol, Variable> kv in variables)
1068 str += " " + kv.Value;
1070 if (bindings != null)
1071 str += " " + bindings;
1072 if (context != null)
1073 str += " (" + context + ")";
1078 internal void DebugWrite (string fmt, params string[] arg)
1080 if (debug_depth > depth)
1082 for (int i = 0; i < depth; i++)
1083 Console.Write (" ");
1084 Console.WriteLine (fmt, arg);
1088 public object SaveValues ()
1090 Dictionary<Variable,Term> values = new Dictionary<Variable,Term> ();
1092 foreach (KeyValuePair<Symbol,Variable> kv in variables)
1093 values[kv.Value] = kv.Value.Value.Clone ();
1097 public void RestoreValues (object values)
1099 foreach (KeyValuePair<Variable,Term> kv
1100 in (Dictionary<Variable,Term>) values)
1101 kv.Key.Value = kv.Value;
1105 public delegate Term Builtin (Domain domain, Variable vari, Term[] args);
1107 private static Domain basic = new Domain ("basic");
1109 static Xexpression ()
1111 basic.DefTerm ("funcall", Funcall.parser);
1112 basic.DefTerm ("varref", Varref.parser);
1114 basic.DefSubr (Fset, "set", true, 1, 1, "=");
1115 basic.DefSubr (Fnot, "not", false, 1, 1, "!");
1116 basic.DefSubr (Fadd, "add", true, 1, -1, "+");
1117 basic.DefSubr (Fmul, "mul", true, 1, -1, "*");
1118 basic.DefSubr (Fsub, "sub", true, 1, -1, "-");
1119 basic.DefSubr (Fdiv, "div", true, 1, -1, "/");
1120 basic.DefSubr (Fmod, "mod", true, 1, 2, "%");
1121 basic.DefSubr (Flogior, "logior", true, 1, -1, "|");
1122 basic.DefSubr (Flogand, "logand", true, 1, -1, "&");
1123 basic.DefSubr (Flsh, "lsh", true, 1, 2, "<<");
1124 basic.DefSubr (Frsh, "rsh", true, 1, 2, ">>");
1125 basic.DefSubr (Feq, "eq", false, 2, -1, "==");
1126 basic.DefSubr (Fnoteq, "noteq", false, 2, 2, "!=");
1127 basic.DefSubr (Flt, "lt", false, 2, -1, "<");
1128 basic.DefSubr (Fle, "le", false, 2, -1, "<=");
1129 basic.DefSubr (Fgt, "gt", false, 2, -1, ">");
1130 basic.DefSubr (Fge, "ge", false, 2, -1, ">=");
1131 basic.DefSubr (Fappend, "append", true, 0, -1);
1132 basic.DefSubr (Fconcat, "concat", true, 0, -1);
1133 basic.DefSubr (Fnth, "nth", false, 2, 2);
1134 basic.DefSubr (Fcopy, "copy", false, 1, 1);
1135 basic.DefSubr (Fins, "ins", true, 2, 2);
1136 basic.DefSubr (Fdel, "del", true, 2, 2);
1137 basic.DefSubr (Feval, "eval", false, 1, 1);
1138 basic.DefSubr (Fbreak, "break", false, 0, 1);
1139 basic.DefSubr (Freturn, "return", false, 0, 1);
1141 basic.DefSpecial (Fand, "and", 1, -1, "&&");
1142 basic.DefSpecial (For, "or", 1, -1, "||");
1143 basic.DefSpecial (Fprogn, "progn", 0, -1, "expr");
1144 basic.DefSpecial (Fif, "if", 2, 3);
1145 basic.DefSpecial (Fwhen, "when", 1, -1);
1146 basic.DefSpecial (Floop, "loop", 1, -1);
1147 basic.DefSpecial (Fwhile, "while", 1, -1);
1148 basic.DefSpecial (Fcond, "cond", 1, -1);
1149 basic.DefSpecial (Fforeach, "foreach", 2, -1);
1150 basic.DefSpecial (Fquote, "quote", 1, 1);
1151 basic.DefSpecial (Ftype, "type", 1, 1);
1152 basic.DefSpecial (Fcatch, "catch", 2, 2);
1153 basic.DefSpecial (Fthrow, "throw", 1, 2);
1156 private static Term Fset (Domain domain, Variable vari, Term[] args)
1158 vari.Value = args[0];
1162 private static Term Fnot (Domain domain, Variable vari, Term[] args)
1164 return args[0].IsTrue ? Zero : One;
1167 private static Term Fadd (Domain domain, Variable vari, Term[] args)
1169 int n = vari == null ? 0 : vari.Value.Intval;
1171 foreach (Term arg in args)
1173 return (vari == null ? new Term (n) : vari.SetValue (n));
1176 private static Term Fmul (Domain domain, Variable vari, Term[] args)
1178 int n = vari == null ? 1 : vari.Value.Intval;
1179 foreach (Term arg in args)
1181 return (vari == null ? new Term (n) : vari.SetValue (n));
1184 private static Term Fsub (Domain domain, Variable vari, Term[] args)
1195 n = vari.Value.Intval;
1198 while (i < args.Length)
1199 n -= args[i++].Intval;
1200 return (vari == null ? new Term (n) : vari.SetValue (n));
1203 private static Term Fdiv (Domain domain, Variable vari, Term[] args)
1214 n = vari.Value.Intval;
1217 while (i < args.Length)
1218 n /= args[i++].Intval;
1219 return (vari == null ? new Term (n) : vari.SetValue (n));
1222 private static Term Fmod (Domain domain, Variable vari, Term[] args)
1224 int n = args[0].Intval % args[1].Intval;
1226 return (vari == null ? new Term (n) : vari.SetValue (n));
1229 private static Term Flogior (Domain domain, Variable vari, Term[] args)
1231 int n = vari == null ? 0 : vari.Value.Intval;
1232 foreach (Term arg in args)
1234 return (vari == null ? new Term (n) : vari.SetValue (n));
1237 private static Term Flogand (Domain domain, Variable vari, Term[] args)
1248 n = vari.Value.Intval;
1251 while (i < args.Length)
1252 n &= args[i++].Intval;
1253 return (vari == null ? new Term (n) : vari.SetValue (n));
1256 private static Term Flsh (Domain domain, Variable vari, Term[] args)
1258 int n = args[0].Intval << args[1].Intval;
1259 return (vari == null ? new Term (n) : vari.SetValue (n));
1262 private static Term Frsh (Domain domain, Variable vari, Term[] args)
1264 int n = args[0].Intval >> args[1].Intval;
1265 return (vari == null ? new Term (n) : vari.SetValue (n));
1268 private static Term Feq (Domain domain, Variable vari, Term[] args)
1272 if (o.objval == null)
1274 for (int i = 1; i < args.Length; i++)
1275 if (args[i].objval != null || args[i].intval != o.intval)
1280 for (int i = 1; i < args.Length; i++)
1281 if (o.objval.Equals (args[i].objval))
1287 private static Term Fnoteq (Domain domain, Variable vari, Term[] args)
1289 return Feq (domain, vari, args);
1292 private static Term Flt (Domain domain, Variable vari, Term[] args)
1294 int n = args[0].Intval;
1296 for (int i = 1; i < args.Length; i++)
1298 int n1 = args[i].Intval;
1306 private static Term Fle (Domain domain, Variable vari, Term[] args)
1308 int n = args[0].Intval;
1309 for (int i = 1; i < args.Length; i++)
1311 int n1 = args[i].Intval;
1319 private static Term Fgt (Domain domain, Variable vari, Term[] args)
1321 int n = args[0].Intval;
1322 for (int i = 1; i < args.Length; i++)
1324 int n1 = args[i].Intval;
1332 private static Term Fge (Domain domain, Variable vari, Term[] args)
1334 int n = args[0].Intval;
1335 for (int i = 1; i < args.Length; i++)
1337 int n1 = args[i].Intval;
1345 private static Term Fappend (Domain domain, Variable vari, Term[] args)
1350 list = new List<Term> ();
1352 list = vari.Value.Listval;
1354 foreach (Term arg in args)
1357 list.AddRange ((List<Term>) arg.objval);
1365 result.objval = list;
1371 private static Term Fconcat (Domain domain, Variable vari, Term[] args)
1378 str = vari.Value.Strval;
1380 foreach (Term arg in args)
1383 str += (string) arg.objval;
1384 else if (arg.IsList)
1385 foreach (Term term in (List<Term>) arg.objval)
1386 str += (char) term.Intval;
1388 str += (char) arg.Intval;
1398 return vari.SetValue (str);
1401 private static Term Fnth (Domain domain, Variable vari, Term[] args)
1407 result.intval = ((string) args[1].objval)[args[0].Intval];
1408 result.objval = null;
1410 else if (args[1].IsList)
1412 result = ((List<Term>) args[1].objval)[args[0].Intval];
1415 throw new Exception ("Term is not enumelable: " + args[1]);
1419 private static Term Fcopy (Domain domain, Variable vari, Term[] args)
1424 result.objval = new List<Term> (args[0].Listval);
1428 private static Term Fins (Domain domain, Variable vari, Term[] args)
1430 Term term = vari.Value;
1434 string str = term.Strval.Insert (args[0].Intval, args[1].Strval);
1435 vari.SetValue (str);
1437 else if (vari.Value.IsList)
1438 vari.Value.Listval.InsertRange (args[0].Intval, args[1].Listval);
1440 throw new Exception ("term is not collection: " + vari.Value);
1444 private static Term Fdel (Domain domain, Variable vari, Term[] args)
1446 if (vari.Value.IsStr)
1449 = vari.Value.Strval.Remove (args[0].Intval,
1450 args[1].Intval - args[0].Intval);
1451 vari.SetValue (str);
1453 else if (vari.Value.IsList)
1454 vari.Value.Listval.RemoveRange (args[0].Intval,
1455 args[1].Intval - args[0].Intval);
1457 throw new Exception ("term is not collection: " + vari.Value);
1461 private static Term Fand (Domain domain, Variable vari, Term[] args)
1463 foreach (Term arg in args)
1464 if (! arg.Eval (domain).IsTrue)
1469 private static Term For (Domain domain, Variable vari, Term[] args)
1471 foreach (Term arg in args)
1472 if (arg.Eval (domain).IsTrue)
1477 private static Term Feval (Domain domain, Variable vari, Term[] args)
1479 return (args[0].Eval (domain));
1482 private static Term Fprogn (Domain domain, Variable vari, Term[] args)
1486 foreach (Term arg in args)
1487 result = arg.Eval (domain);
1491 private static Term Fif (Domain domain, Variable vari, Term[] args)
1493 if (args[0].Eval (domain).IsTrue)
1494 return args[1].Eval (domain);
1495 if (args.Length == 2)
1497 return args[2].Eval (domain);
1500 private static Term Fwhen (Domain domain, Variable vari, Term[] args)
1502 if (! args[0].Eval (domain).IsTrue)
1505 for (int i = 1; i < args.Length; i++)
1506 result = args[i].Eval (domain);
1510 private static Term Freturn (Domain domain, Variable vari, Term[] args)
1512 domain.ThrowReturn ();
1513 return args.Length == 0 ? Zero : args[0];
1516 private static Term Fbreak (Domain domain, Variable vari, Term[] args)
1518 domain.ThrowBreak ();
1519 return args.Length == 0 ? Zero : args[0];
1522 private static Term Floop (Domain domain, Variable vari, Term[] args)
1526 domain.Catch (CatchTag.Break);
1527 while (! domain.Thrown)
1528 foreach (Term arg in args)
1530 result = arg.Eval (domain);
1540 private static Term Fwhile (Domain domain, Variable vari, Term[] args)
1544 domain.Catch (CatchTag.Break);
1545 while (! domain.Thrown && args[0].Eval (domain).IsTrue)
1546 for (int i = 1; i < args.Length; i++)
1548 result = args[i].Eval (domain);
1558 private static Term Fcond (Domain domain, Variable vari, Term[] args)
1560 foreach (Term arg in args)
1562 List<Term> list = arg.Listval;
1563 Term result = list[0].Eval (domain);
1567 for (int i = 1; i < list.Count; i++)
1570 result = list[i].Eval (domain);
1581 private static Term Fforeach (Domain domain, Variable vari,
1584 Term result = args[0].Eval (domain);
1587 List<Term> list = result.Listval;
1588 Bindings current = domain.bindings;
1591 domain.Catch (CatchTag.Break);
1592 foreach (Term term in list)
1594 domain.Bind (vari, term);
1596 for (int i = 1; i < args.Length; i++)
1598 result = args[i].Eval (domain);
1603 domain.UnboundTo (current);
1612 private static Term Fquote (Domain domain, Variable vari, Term[] args)
1614 return new Term (args[0]);
1617 private static Term Ftype (Domain domain, Variable vari, Term[] args)
1623 if (args[0].IsSymbol)
1630 public static Term Fcatch (Domain domain, Variable vari, Term[] args)
1634 domain.Catch (new CatchTag (args[0].Symval));
1635 result = args[1].Eval (domain);
1642 public static Term Fthrow (Domain domain, Variable vari, Term[] args)
1644 domain.ThrowTag (new CatchTag (args[0].Symval));
1645 return (args.Length == 1 ? Zero : args[1]);
1648 public delegate TermValue TermParser (Domain domain, XmlNode node);
1650 public class TermType
1652 public readonly Symbol type;
1653 internal readonly TermParser parser;
1655 public TermType (Symbol type, TermParser parser)
1658 this.parser = parser;
1662 public abstract class TermValue
1664 public virtual Term Eval (Domain domain) { return new Term (this); }
1665 public virtual TermValue Clone () { return this; }
1668 private class Varref : TermValue
1670 private Symbol name;
1671 private Variable vari;
1673 public Varref (Symbol name) { this.name = name; }
1675 public override Term Eval (Domain domain)
1677 if (vari == null || vari.domain != domain)
1678 vari = domain.GetVar (name, true);
1682 internal static TermValue parser (Domain domain, XmlNode node)
1684 return new Varref ((Symbol) node.Attributes[Qvname].Value);
1687 public override string ToString ()
1689 return "<varref vname=\"" + name + "\"/>";
1693 private class Funcall : TermValue
1695 internal Function func;
1696 internal Variable vari;
1697 internal Term[] args;
1699 public Funcall (Function func, Variable vari, Term[] args)
1703 int nargs = args.Length;
1704 if (nargs < func.min_arg
1705 || (func.max_arg >= 0 && nargs > func.max_arg))
1706 throw_exception ("Invalid number of arguments to {0}: ",
1714 internal static TermValue parser (Domain domain, XmlNode node)
1716 Symbol fname = node.Name;
1719 if (fname == Qfuncall)
1720 fname = node.Attributes[Qfname].Value;
1721 Function func = domain.GetFunc (fname);
1723 attr = node.Attributes[Qvname];
1724 vari = attr == null ? null : domain.GetVar (attr.Value, true);
1725 XmlNodeList nlist = node.ChildNodes;
1726 int nargs = nlist.Count;
1727 Term[] args = new Term[nargs];
1728 for (int i = 0; i < nargs; i++)
1729 args[i] = new Term (domain, nlist[i]);
1730 return new Funcall (func, vari, args);
1733 public override Term Eval (Domain domain)
1735 domain.DebugWrite (ToString ());
1737 Term result = func.Call (domain, vari, args);
1739 domain.DebugWrite ("=> {0}", result.ToString ());
1743 public override TermValue Clone ()
1745 return new Funcall (func, vari, args);
1748 public override string ToString ()
1750 string str = "<" + func.name;
1752 str += " vname=\"" + vari.name + "\"";
1756 if (func is Function.SpecialForm)
1758 for (int i = 0; i < args.Length; i++)
1762 foreach (Term e in args)
1764 return (str + "</" + func.name + ">");
1771 public object objval;
1773 // <integer>...</integer>
1774 public Term (int i) { intval = i; objval = null; }
1775 // <symbol>...</symbol>
1776 public Term (Symbol name) { intval = 0; objval = name; }
1777 // <string>...</string>
1778 public Term (string str) { intval = 0; objval = str; }
1780 public Term (List<Term> list) { intval = 0; objval = list; }
1782 public Term (Term term) { intval = term.intval; objval = term.objval; }
1783 public Term (TermValue obj) { intval = 0; objval = obj; }
1785 public Term (Domain domain, XmlNode node)
1787 Symbol name = node.Name;
1789 if (name == Qinteger)
1791 intval = parse_integer (node.InnerText);
1797 if (name == Qsymbol)
1798 objval = (Symbol) node.InnerText;
1799 else if (name == Qstring)
1800 objval = node.InnerText.Clone ();
1801 else if (name == Qlist)
1803 List<Term> list = new List<Term> ();
1804 for (node = node.FirstChild; node != null;
1805 node = node.NextSibling)
1806 list.Add (new Term (domain, node));
1813 if (domain.termtypes.TryGetValue (name, out term_type))
1814 objval = term_type.parser (domain, node);
1817 Funcall funcall = (Funcall) Funcall.parser (domain, node);
1818 if (funcall.func is Function.Macro)
1820 Term result = funcall.Eval (domain);
1821 intval = result.intval;
1822 objval = result.objval;
1831 // <varref vname="VNAME"/>
1832 public Term (Domain domain, Symbol vname)
1835 objval = new Varref (vname);
1838 // <funcall fname="FNAME">...</funcall>
1839 public Term (Domain domain, Symbol fname, Term[] args)
1840 : this (domain, fname, Qnull, args) { }
1842 // <funcall fname="FNAME" vname="VNAME">...</funcall>
1843 public Term (Domain domain, Symbol fname, Symbol vname, Term[] args)
1847 Function func = domain.GetFunc (fname);
1848 Variable vari = vname == Qnull ? null : domain.GetVar (vname, true);
1849 Funcall funcall = new Funcall (func, vari, args);
1850 if (func is Function.Macro)
1852 Term result = funcall.Eval (domain);
1853 intval = result.intval;
1854 objval = result.objval;
1860 public object Objval {
1863 throw new Exception ("term is an integer: " + this);
1871 throw new Exception ("term is not integer: " + this);
1876 public string Strval {
1879 throw new Exception ("term is not string: " + this);
1880 return (string) objval;
1884 public string Symval {
1887 throw new Exception ("term is not symbol: " + this);
1888 return (Symbol) objval;
1892 public List<Term> Listval {
1895 throw new Exception ("term is not list: " + this);
1896 return (List<Term>) objval;
1900 public bool IsTrue {
1902 return (objval == null
1904 : objval is List<Term>
1905 ? (((List<Term>) objval).Count != 0)
1909 public bool IsInt { get { return (objval == null); } }
1910 public bool IsStr { get { return (objval is string); } }
1911 public bool IsSymbol { get { return (objval is Symbol); } }
1912 public bool IsList { get { return (objval is List<Term>); } }
1914 public bool IsType (Type type)
1916 return (objval == null ? type == typeof (int)
1917 : type == objval.GetType ());
1920 public Term Eval (Domain domain)
1922 if (objval == null || objval is Symbol || objval is string)
1924 if (objval is List<Term>)
1925 return new Term ((List<Term>) objval);
1926 return ((TermValue) objval).Eval (domain);
1929 public Term Clone ()
1931 if (objval == null || objval is Symbol || objval is string)
1933 if (objval is List<Term>)
1935 List<Term> list = new List<Term> ();
1936 list.InsertRange (0, ((List<Term>) objval));
1937 return new Term (list);
1939 return new Term (((TermValue) objval).Clone ());
1942 public override string ToString ()
1947 str = "<integer>" + intval + "</integer>";
1948 else if (objval is Symbol)
1949 str = "<symbol>" + objval + "</symbol>";
1950 else if (objval is string)
1951 str = "<string>" + objval + "</string>";
1952 else if (objval is List<Term>)
1955 foreach (Term e in (List<Term>) objval)
1959 else if (objval is Term)
1960 str = "<quote>" + objval + "</quote>";
1961 else if (objval is TermValue)
1962 str = ((TermValue) objval).ToString ();
1964 throw new Exception ("invalid Term object: " + objval);
1969 static private Term Zero = new Term (0);
1970 static private Term One = new Term (1);
1971 static private Term TermInt = new Term (Qinteger);
1972 static private Term TermStr = new Term (Qstring);
1973 static private Term TermSymbol = new Term (Qsymbol);
1974 static private Term TermList = new Term (Qlist);
1975 static private Term TermTerm = new Term ((Symbol) "term");
1977 internal static int parse_integer (string str)
1979 int len = str.Length;
1980 bool negative = false;
1983 return (len == 0 ? 0 : str[0] - '0');
1990 if ((c == '0' || c == '#') && str[1] == 'x')
1993 for (int idx = 2; idx < len; idx++)
1999 i = i * 16 + (c - '0');
2003 i = i * 16 + (c - 'A');
2007 i = i * 16 + (c - 'a');
2016 for (int idx = 1; idx < len; idx++)
2019 if (c < '0' || c > '9')
2021 i = i * 10 + (c - '0');
2023 return negative ? - i : i;
2026 private Term[] terms;
2028 public static Term[] ParseTerms (Domain domain, XmlNode node)
2031 for (XmlNode n = node; n != null; n = n.NextSibling)
2032 if (n.NodeType == XmlNodeType.Element)
2034 if (n.Name == Qdefun)
2035 domain.Defun (n, true);
2036 else if (n.Name == Qdefmacro)
2037 domain.Defmacro (n, true);
2038 else if (n.Name == Qdefvar)
2043 Term[] terms = new Term[nterms];
2045 for (XmlNode n = node; n != null; n = n.NextSibling)
2046 if (n.NodeType == XmlNodeType.Element)
2048 if (n.Name == Qdefun)
2049 domain.Defun (n, false);
2050 else if (n.Name == Qdefmacro)
2051 domain.Defmacro (n, false);
2052 else if (n.Name != Qdefvar)
2053 terms[i++]= new Term (domain, n);
2058 public static Term Eval (Domain domain, Term[] terms)
2060 Term result = new Term (0);
2061 foreach (Term term in terms)
2064 if (result.Objval is Funcall)
2065 while ((result = result.Eval (domain)).Objval is Funcall);
2071 public Xexpression (Domain domain, XmlNode node)
2073 terms = ParseTerms (domain, node);
2076 public Xexpression (Domain domain, string url)
2078 XmlDocument doc = new XmlDocument (Symbol.NameTable);
2081 using (XmlTextReader reader = new XmlTextReader (url, doc.NameTable))
2085 } while (reader.NodeType != XmlNodeType.None
2086 && (reader.NodeType != XmlNodeType.Element
2087 || reader.Name != Qexpr));
2088 if (reader.NodeType == XmlNodeType.None)
2089 throw new Exception ("Node <expr> not found");
2090 node = doc.ReadNode (reader);
2092 terms = ParseTerms (domain, node.FirstChild);
2095 public Term Eval (Domain domain)
2101 domain.Catch (CatchTag.Return);
2102 foreach (Term term in terms)
2104 result = term.Eval (domain);
2114 public override string ToString ()
2117 for (int i = 0; i < terms.Length; i++)