2 using System.Collections;
3 using System.Collections.Generic;
7 namespace System.Xml.Expression
9 public class Xexpression
11 public static int debug_level = 0;
13 public struct Symbol : IEquatable<Symbol>
15 private static NameTable nt = new NameTable ();
19 public Symbol (string str)
24 public static implicit operator Symbol (string str)
26 return new Symbol (str);
29 public static implicit operator string (Symbol name)
34 public static bool operator== (Symbol n1, Symbol n2)
36 return (object) n1.name == (object) n2.name;
39 public static bool operator!= (Symbol n1, Symbol n2)
41 return (object) n1.name != (object) n2.name;
44 public static bool operator== (Symbol n1, string n2)
46 return (object) n1.name == (object) n2;
49 public static bool operator!= (Symbol n1, string n2)
51 return (object) n1.name != (object) n2;
54 public static bool operator== (string n1, Symbol n2)
56 return (object) n1 == (object) n2.name;
59 public static bool operator!= (string n1, Symbol n2)
61 return (object) n1 != (object) n2.name;
64 public bool Equals (Symbol name)
66 return Object.ReferenceEquals (this.name, name.name);
69 public override bool Equals (object obj)
71 return Object.ReferenceEquals (this.name, obj);
74 public override int GetHashCode ()
76 return name.GetHashCode ();
79 public static NameTable Table { get { return nt; } }
81 public override string ToString () { return name; }
84 private static Symbol Qexpr = "expr";
86 private static Symbol Qnull = "";
87 private static Symbol Qfuncall = "funcall";
88 private static Symbol Qinteger = "integer";
89 private static Symbol Qstring = "string";
90 private static Symbol Qsymbol = "symbol";
91 private static Symbol Qlist = "list";
93 private static Symbol Qdefun = "defun";
94 private static Symbol Qdefmacro = "defmacro";
95 private static Symbol Qfname = "fname";
96 private static Symbol Qargs = "args";
97 private static Symbol Qfixed = "fixed";
98 private static Symbol Qoptional = "optional";
99 private static Symbol Qrest = "rest";
101 private static Symbol Qdefvar = "defvar";
102 private static Symbol Qvname = "vname";
103 private static Symbol Qdescription = "description";
104 private static Symbol Qrange = "range";
106 public abstract class Function
109 public int min_arg, max_arg;
111 public Function () { }
113 public Function (Symbol name, int min_arg, int max_arg)
116 this.min_arg = min_arg;
117 this.max_arg = max_arg;
120 public abstract Term Call (Domain domain, Variable vari, Term[] args);
122 public override string ToString ()
127 internal class Subroutine : Function
129 public Builtin builtin;
132 public Subroutine (Builtin builtin, Symbol name, bool setvar,
133 int min_arg, int max_arg)
134 : base (name, min_arg, max_arg)
136 this.builtin = builtin;
137 this.setvar = setvar;
140 public override Term Call (Domain domain, Variable vari, Term[] args)
144 args = (Term[]) args.Clone ();
145 for (int i = 0; i < args.Length; i++)
147 args[i] = args[i].Eval (domain);
152 return builtin (domain, vari, args);
156 internal class SpecialForm : Function
158 public Builtin builtin;
160 public SpecialForm (Builtin builtin, Symbol name,
161 int min_arg, int max_arg)
162 : base (name, min_arg, max_arg)
164 this.builtin = builtin;
167 public override Term Call (Domain domain, Variable vari, Term[] args)
169 return builtin (domain, vari, args);
173 private static void parse_head (Domain domain, XmlNode node,
175 out int min_arg, out int max_arg,
181 name = node.Attributes[Qfname].Value;
183 node = node.FirstChild;
184 if (node != null && node.Name == Qargs)
187 for (n = node.FirstChild; n != null; n = n.NextSibling)
189 if (n.Name == Qfixed)
191 else if (n.Name == Qoptional)
193 else if (n.Name == Qrest)
196 throw new Exception ("Invalid argument type: " + n);
199 max_arg = nfixed + noptional + nrest;
200 args = new Variable[max_arg];
202 for (int i = 0; i < max_arg; n = n.NextSibling)
203 args[i++] = domain.Defvar ((Symbol) n.Attributes[0].Value);
209 min_arg = max_arg = 0;
214 private static void parse_body (Domain domain, XmlNode node,
217 for (node = node.FirstChild; node != null; node = node.NextSibling)
218 if (node.Name != Qdescription
219 && node.Name != Qargs)
222 for (XmlNode n = node; n != null; n = n.NextSibling)
226 body = new Term[nterms];
227 for (nterms = 0; node != null; node = node.NextSibling, nterms++)
228 body[nterms] = new Term (domain, node);
234 internal class Macro : Function
236 internal Variable[] args;
237 internal Term[] body;
239 public Macro (Domain domain, XmlNode node)
241 parse_head (domain, node, out name, out min_arg, out max_arg,
245 public void SetBody (Domain domain, XmlNode node)
247 parse_body (domain, node, out body);
250 public override Term Call (Domain domain, Variable vari, Term[] args)
252 Bindings current = domain.bindings;
256 for (int i = 0; i < min_arg; i++)
257 domain.Bind (this.args[i], args[i]);
261 domain.Catch (CatchTag.Return);
262 foreach (Term term in body)
264 result = term.Eval (domain);
273 domain.UnboundTo (current);
279 internal class Lambda : Function
281 internal Variable[] args;
282 internal Term[] body;
284 public Lambda (Domain domain, XmlNode node)
286 parse_head (domain, node, out name, out min_arg, out max_arg,
290 public Lambda (Domain domain, Symbol name, Symbol[] args)
300 for (i = 0; i < args.Length; i++, nfixed++)
301 if (args[i] == Qoptional || args[i] == Qrest)
305 if (args[i] == Qoptional)
307 for (i++; i < args.Length; i++, noptional++)
308 if (args[i] == Qrest)
315 max_arg = nfixed + noptional + nrest;
316 this.args = new Variable[max_arg];
318 for (i = j = 0; j < this.args.Length; i++)
319 if (args[i] != Qoptional || args[i] != Qrest)
320 this.args[j++] = domain.Defvar (args[i]);
324 min_arg = max_arg = 0;
328 public void SetBody (Domain domain, XmlNode node)
330 parse_body (domain, node, out body);
333 public void SetBody (Term[] body)
338 public override Term Call (Domain domain, Variable vari, Term[] args)
340 Bindings current = domain.bindings;
347 Term[] newargs = new Term[args.Length];
348 for (i = 0; i < min_arg; i++)
349 newargs[i] = args[i].Eval (domain);
352 for (i = 0; i < min_arg; i++)
353 domain.Bind (this.args[i], args[i]);
357 domain.Catch (CatchTag.Return);
358 foreach (Term term in body)
360 result = term.Eval (domain);
369 domain.UnboundTo (current);
376 public class Variable
378 public Domain domain;
379 public readonly Symbol name;
381 protected Term default_val;
385 public Variable (Domain domain, Symbol name, Term val)
387 this.domain = domain;
393 public virtual bool ValueP (Term val) { return true; }
395 public Variable Clone (Domain domain)
397 Variable v = new Variable (domain, name, val);
399 v.default_val = default_val;
408 if (! ValueP (value))
409 throw new Exception ("Invalid value: " + value);
414 public Term SetValue (int i)
421 public Term SetValue (string s)
427 public Term DefaultValue
429 get { return default_val; }
431 if (! ValueP (value))
432 throw new Exception ("Invalid value: " + value);
437 public virtual object Range
439 get { return range; }
440 set { range = value; }
443 public override string ToString () { return name + "(" + val + ")"; }
445 public class Int : Variable
449 private static bool SubsetP (int[] r1, int[] r2)
453 for (int i = 0; i < r1.Length; i += 2)
456 for (j = 0; j < r2.Length; j += 2)
457 if (r2[j] <= r1[i] && r2[j + 1] >= r1[i + 1])
465 private static bool SubsetP (int val, int[] r)
469 for (int i = 0; i < r.Length; i += 2)
470 if (r[i] <= val && r[i + 1] >= val)
475 public Int (Domain domain, Symbol name, string description,
476 int value, int[] range)
477 : base (domain, name, new Term (value))
479 if (! SubsetP (value, range))
480 throw new Exception ("Invalid value: " + value);
486 public override bool ValueP (Term term)
490 return SubsetP (term.Intval, range);
493 public override object Range {
494 get { return range; }
496 int[] r = (int[]) value;
497 if (! SubsetP (r, range)
498 || ! SubsetP (val.Intval, r)
499 || ! SubsetP (default_val.Intval, r))
500 throw new Exception ("Invalid range");
506 public class Str : Variable
508 public string[] range;
510 private static bool SubsetP (string[] r1, string[] r2)
514 foreach (string s in r1)
515 if (! SubsetP (s, r2))
520 private static bool SubsetP (string str, string[] r)
524 foreach (string s in r)
530 public Str (Domain domain, Symbol name, string description,
531 string value, string[] range)
532 : base (domain, name, new Term (value))
534 if (! SubsetP (value, range))
535 throw new Exception ("Invalid value: " + value);
541 public override bool ValueP (Term term)
543 if (! (term.objval is string))
545 return SubsetP (term.Strval, range);
548 public override object Range {
549 get { return range; }
551 string[] r = (string[]) value;
552 if (! SubsetP (r, range)
553 || ! SubsetP (val.Strval, r)
554 || ! SubsetP (default_val.Strval, r))
555 throw new Exception ("Invalid range");
561 public class Sym : Variable
563 public Symbol[] range;
565 private static bool SubsetP (Symbol[] r1, Symbol[] r2)
569 foreach (Symbol n in r1)
570 if (! SubsetP (n, r2))
575 private static bool SubsetP (Symbol name, Symbol[] r)
579 foreach (Symbol n in r)
585 public Sym (Domain domain, Symbol name, string description,
586 Symbol value, Symbol[] range)
587 : base (domain, name, new Term (value))
589 if (! SubsetP (value, range))
590 throw new Exception ("Invalid value: " + value);
596 public override bool ValueP (Term term)
598 if (! (term.objval is Symbol))
600 return SubsetP (term.Symval, range);
603 public override object Range {
604 get { return range; }
606 Symbol[] r = (Symbol[]) value;
607 if (! SubsetP (r, range)
608 || ! SubsetP (val.Symval, r)
609 || ! SubsetP (default_val.Symval, r))
610 throw new Exception ("Invalid range");
617 internal class Bindings
619 private Variable vari;
620 private Term old_value;
621 private Bindings next;
623 private Bindings (Variable vari)
626 old_value = vari.Value;
629 public static Bindings Bind (Bindings bindings, Variable vari, Term val)
631 Bindings b = new Bindings (vari);
638 internal Bindings UnboundTo (Bindings boundary)
640 for (Bindings b = this; b != boundary; b = b.next)
641 b.vari.Value = b.old_value;
645 public override string ToString ()
647 string str = "(bindings";
648 for (Bindings b = this; b != null; b = b.next)
649 str += " " + vari.name + "=" + b.old_value;
655 internal class ThrowException : Exception
660 public ThrowException (Symbol tag, object value) : base ()
668 internal class CatchTag : IEquatable<CatchTag>
672 public CatchTag (Symbol name) { val = name.name; }
673 private CatchTag (int i) { val = i; }
675 public static CatchTag Return = new CatchTag (0);
676 public static CatchTag Break = new CatchTag (1);
678 public static bool operator== (CatchTag t1, CatchTag t2)
679 { return t1.val == t2.val; }
681 public static bool operator!= (CatchTag t1, CatchTag t2)
682 { return t1.val != t2.val; }
684 public bool Equals (CatchTag tag) { return this.val == tag.val; }
685 public override bool Equals (object val) { return this.val == val; }
687 public override int GetHashCode () { return val.GetHashCode (); }
693 public object context;
694 public int depth = 0;
696 internal Dictionary<Symbol, TermType> termtypes
697 = new Dictionary<Symbol, TermType> ();
698 internal Dictionary<Symbol, Function> functions
699 = new Dictionary<Symbol, Function> ();
700 internal Dictionary<Symbol, Variable> variables
701 = new Dictionary<Symbol, Variable> ();
702 internal Bindings bindings;
703 private Stack<CatchTag> catch_stack = new Stack<CatchTag> ();
704 private int catch_count = 0;
706 internal Domain (Symbol name) { this.name = name; }
708 public Domain (Symbol name, object context)
709 : this (name, basic, context) { }
711 public Domain (Symbol name, Domain parent, object context) : this (name)
713 termtypes = new Dictionary<Symbol, TermType> (parent.termtypes);
714 functions = new Dictionary<Symbol, Function> (parent.functions);
715 variables = new Dictionary<Symbol, Variable> (parent.variables);
716 this.context = context;
719 internal void Bind (Variable vari, Term value)
721 bindings = Bindings.Bind (bindings, vari, value);
724 internal void UnboundTo (Bindings boundary)
726 if (bindings != null)
727 bindings = bindings.UnboundTo (boundary);
730 internal void Catch (CatchTag tag)
732 catch_stack.Push (tag);
736 internal void Uncatch ()
739 if (catch_count > catch_stack.Count)
744 get { return catch_count < catch_stack.Count; }
747 internal void ThrowReturn ()
749 foreach (CatchTag tag in catch_stack)
752 if (tag == CatchTag.Return)
757 internal void ThrowBreak ()
759 if (catch_stack.Peek () != CatchTag.Break)
760 throw new Exception ("No outer loop to break");
764 internal void ThrowTag (CatchTag tag)
766 foreach (CatchTag elt in catch_stack)
774 public void DefTerm (Symbol name, TermParser parser)
776 if (termtypes.ContainsKey (name)
777 || functions.ContainsKey (name))
778 throw new Exception ("already defined: " + name);
779 termtypes[name] = new TermType (name, parser);
782 public void DefSubr (Builtin builtin, string str, bool setvar,
783 int min_arg, int max_arg, params string[] aliases)
786 if (termtypes.ContainsKey (name))
787 throw new Exception ("already defined as termtype: " + name);
788 Function func = new Function.Subroutine (builtin, name, setvar,
790 functions[name] = func;
791 foreach (string a in aliases)
792 functions[(Symbol) a] = func;
795 public void DefSpecial (Builtin builtin, string str,
796 int min_arg, int max_arg,
797 params string[] aliases)
800 if (termtypes.ContainsKey (name))
801 throw new Exception ("already defined as termtype: " + name);
802 Function func = new Function.SpecialForm (builtin, name,
804 functions[name] = func;
805 foreach (string a in aliases)
806 functions[(Symbol) a] = func;
809 public void DefAlias (string alias, string str)
811 functions[(Symbol) alias] = functions[(Symbol) str];
814 public void Defun (Symbol name, Symbol[] args, Term[] body,
819 if (termtypes.ContainsKey (name))
820 throw new Exception ("already defined as termtype: " + name);
821 if (prototype || ! functions.TryGetValue (name, out func))
823 func = new Function.Lambda (this, name, args);
824 functions[name] = func;
827 ((Function.Lambda) func).SetBody (body);
830 public void Defun (XmlNode node, bool prototype)
832 Symbol name = node.Attributes[Qfname].Value;
833 if (termtypes.ContainsKey (name))
834 throw new Exception ("already defined as termtype: " + name);
837 if (prototype || ! functions.TryGetValue (name, out func))
839 func = new Function.Lambda (this, node);
840 functions[name] = func;
843 ((Function.Lambda) func).SetBody (this, node);
846 public void Defun (Function func)
848 functions[func.name] = func;
851 public void Defmacro (XmlNode node, bool prototype)
853 Symbol name = node.Attributes[Qfname].Value;
854 if (termtypes.ContainsKey (name))
855 throw new Exception ("already defined as termtype: " + name);
858 if (prototype || ! functions.TryGetValue (name, out func))
860 func = new Function.Macro (this, node);
861 functions[name] = func;
864 ((Function.Macro) func).SetBody (this, node);
867 public Variable Defvar (XmlNode node)
869 Symbol name = node.Attributes[0].Value;
873 node = node.FirstChild;
874 if (node != null && node.Name == Qdescription)
876 desc = node.InnerText;
877 node = node.NextSibling;
883 Symbol type = node.Name;
884 XmlNodeList range_list = null;
886 string val = node.InnerText;
888 node = node.NextSibling;
891 range_list = node.ChildNodes;
892 nranges = range_list.Count;
895 if (type == Qinteger)
897 int intval = parse_integer (val);
899 if (range_list != null)
901 range = new int[nranges * 2];
902 for (int i = 0; i < nranges; i++)
904 XmlNode n = range_list[i];
905 if (n.Name == Qrange)
908 = parse_integer (n.FirstChild.InnerText);
910 = parse_integer (n.LastChild.InnerText);
916 = parse_integer (n.FirstChild.InnerText);
921 if (variables.TryGetValue (name, out vari))
923 if (! (vari is Variable.Int))
924 throw new Exception ("Inalid value");
925 vari = (Variable) vari.Clone (this);
926 Term v = new Term (intval);
928 vari.DefaultValue = v;
933 vari = new Variable.Int (this, name, desc, intval, range);
935 else if (type == Qstring)
937 string[] range = null;
938 if (range_list != null)
940 range = new string[nranges];
941 for (int i = 0; i < nranges; i++)
942 range[i] = range_list[i].FirstChild.InnerText;
945 if (variables.TryGetValue (name, out vari))
947 if (! (vari is Variable.Str))
948 throw new Exception ("Invalid value");
949 vari = (Variable) vari.Clone (this);
950 Term v = new Term (val);
952 vari.DefaultValue = v;
957 vari = new Variable.Str (this, name, desc, val, range);
959 else if (type == Qsymbol)
961 Symbol[] range = null;
962 if (range_list != null)
964 range = new Symbol[nranges];
965 for (int i = 0; i < nranges; i++)
966 range[i] = range_list[i].FirstChild.InnerText;
969 if (variables.TryGetValue (name, out vari))
971 if (! (vari is Variable.Sym))
972 throw new Exception ("Invalid value");
973 vari = (Variable) vari.Clone (this);
974 Term v = new Term (val);
976 vari.DefaultValue = v;
981 vari = new Variable.Sym (this, name, desc, val, range);
984 throw new Exception ("Unknown type: " + type);
988 if (variables.TryGetValue (name, out vari))
989 vari = (Variable) vari.Clone (this);
991 vari = new Variable (this, name, Zero);
993 variables[name] = vari;
997 public Variable Defvar (Variable vari)
999 vari = vari.Clone (this);
1000 variables[vari.name] = vari;
1004 internal Variable Defvar (Symbol name)
1006 Variable vari = new Variable (this, name, Zero);
1007 variables[name] = vari;
1011 internal Function GetFunc (Symbol name)
1015 if (! functions.TryGetValue (name, out func))
1016 throw new Exception ("Unknown function: " + name);
1020 public bool CopyFunc (Domain domain, Symbol name)
1022 Function func = GetFunc (name);
1024 domain.functions[name] = func;
1028 public void CopyFunc (Domain domain)
1030 foreach (KeyValuePair<Symbol, Function> kv in functions)
1031 domain.functions[kv.Key] = kv.Value;
1034 public Variable GetVar (Symbol name, bool create)
1038 if (! variables.TryGetValue (name, out vari))
1042 variables[name] = vari = new Variable (this, name, Zero);
1047 public override string ToString ()
1049 string str = "<(functions";
1050 foreach (KeyValuePair<Symbol, Function> kv in functions)
1051 str += " " + kv.Key;
1052 str += ") (variabls";
1053 foreach (KeyValuePair<Symbol, Variable> kv in variables)
1054 str += " " + kv.Value;
1056 if (bindings != null)
1057 str += " " + bindings;
1058 if (context != null)
1059 str += " (" + context + ")";
1064 internal void DebugWrite (bool head, string fmt, params string[] arg)
1066 if (debug_level > depth)
1070 Console.WriteLine ();
1071 for (int i = 0; i < depth; i++)
1072 Console.Write (" ");
1074 Console.Write (fmt, arg);
1078 public object SaveValues ()
1080 Dictionary<Variable,Term> values = new Dictionary<Variable,Term> ();
1082 foreach (KeyValuePair<Symbol,Variable> kv in variables)
1083 values[kv.Value] = kv.Value.Value.Clone ();
1087 public void RestoreValues (object values)
1089 foreach (KeyValuePair<Variable,Term> kv
1090 in (Dictionary<Variable,Term>) values)
1091 kv.Key.Value = kv.Value;
1095 public delegate Term Builtin (Domain domain, Variable vari, Term[] args);
1097 private static Domain basic = new Domain ("basic");
1099 static Xexpression ()
1101 basic.DefTerm ("funcall", Funcall.parser);
1102 basic.DefTerm ("varref", Varref.parser);
1104 basic.DefSubr (Fset, "set", true, 1, 1, "=");
1105 basic.DefSubr (Fnot, "not", false, 1, 1, "!");
1106 basic.DefSubr (Fadd, "add", true, 1, -1, "+");
1107 basic.DefSubr (Fmul, "mul", true, 1, -1, "*");
1108 basic.DefSubr (Fsub, "sub", true, 1, -1, "-");
1109 basic.DefSubr (Fdiv, "div", true, 1, -1, "/");
1110 basic.DefSubr (Fmod, "mod", true, 1, 2, "%");
1111 basic.DefSubr (Flogior, "logior", true, 1, -1, "|");
1112 basic.DefSubr (Flogand, "logand", true, 1, -1, "&");
1113 basic.DefSubr (Flsh, "lsh", true, 1, 2, "<<");
1114 basic.DefSubr (Frsh, "rsh", true, 1, 2, ">>");
1115 basic.DefSubr (Feq, "eq", false, 2, -1, "==");
1116 basic.DefSubr (Fnoteq, "noteq", false, 2, 2, "!=");
1117 basic.DefSubr (Flt, "lt", false, 2, -1, "<");
1118 basic.DefSubr (Fle, "le", false, 2, -1, "<=");
1119 basic.DefSubr (Fgt, "gt", false, 2, -1, ">");
1120 basic.DefSubr (Fge, "ge", false, 2, -1, ">=");
1121 basic.DefSubr (Fappend, "append", true, 0, -1);
1122 basic.DefSubr (Fconcat, "concat", true, 0, -1);
1123 basic.DefSubr (Fnth, "nth", false, 2, 2);
1124 basic.DefSubr (Fcopy, "copy", false, 1, 1);
1125 basic.DefSubr (Fins, "ins", true, 2, 2);
1126 basic.DefSubr (Fdel, "del", true, 2, 2);
1127 basic.DefSubr (Feval, "eval", false, 1, 1);
1128 basic.DefSubr (Fbreak, "break", false, 0, 1);
1129 basic.DefSubr (Freturn, "return", false, 0, 1);
1131 basic.DefSpecial (Fand, "and", 1, -1, "&&");
1132 basic.DefSpecial (For, "or", 1, -1, "||");
1133 basic.DefSpecial (Fprogn, "progn", 0, -1, "expr");
1134 basic.DefSpecial (Fif, "if", 2, 3);
1135 basic.DefSpecial (Fwhen, "when", 1, -1);
1136 basic.DefSpecial (Floop, "loop", 1, -1);
1137 basic.DefSpecial (Fwhile, "while", 1, -1);
1138 basic.DefSpecial (Fcond, "cond", 1, -1);
1139 basic.DefSpecial (Fforeach, "foreach", 2, -1);
1140 basic.DefSpecial (Fquote, "quote", 1, 1);
1141 basic.DefSpecial (Ftype, "type", 1, 1);
1142 basic.DefSpecial (Fcatch, "catch", 2, 2);
1143 basic.DefSpecial (Fthrow, "throw", 1, 2);
1146 private static Term Fset (Domain domain, Variable vari, Term[] args)
1148 vari.Value = args[0];
1152 private static Term Fnot (Domain domain, Variable vari, Term[] args)
1154 return args[0].IsTrue ? Zero : One;
1157 private static Term Fadd (Domain domain, Variable vari, Term[] args)
1159 int n = vari == null ? 0 : vari.Value.Intval;
1161 foreach (Term arg in args)
1163 return (vari == null ? new Term (n) : vari.SetValue (n));
1166 private static Term Fmul (Domain domain, Variable vari, Term[] args)
1168 int n = vari == null ? 1 : vari.Value.Intval;
1169 foreach (Term arg in args)
1171 return (vari == null ? new Term (n) : vari.SetValue (n));
1174 private static Term Fsub (Domain domain, Variable vari, Term[] args)
1185 n = vari.Value.Intval;
1188 while (i < args.Length)
1189 n -= args[i++].Intval;
1190 return (vari == null ? new Term (n) : vari.SetValue (n));
1193 private static Term Fdiv (Domain domain, Variable vari, Term[] args)
1204 n = vari.Value.Intval;
1207 while (i < args.Length)
1208 n /= args[i++].Intval;
1209 return (vari == null ? new Term (n) : vari.SetValue (n));
1212 private static Term Fmod (Domain domain, Variable vari, Term[] args)
1214 int n = args[0].Intval % args[1].Intval;
1216 return (vari == null ? new Term (n) : vari.SetValue (n));
1219 private static Term Flogior (Domain domain, Variable vari, Term[] args)
1221 int n = vari == null ? 0 : vari.Value.Intval;
1222 foreach (Term arg in args)
1224 return (vari == null ? new Term (n) : vari.SetValue (n));
1227 private static Term Flogand (Domain domain, Variable vari, Term[] args)
1238 n = vari.Value.Intval;
1241 while (i < args.Length)
1242 n &= args[i++].Intval;
1243 return (vari == null ? new Term (n) : vari.SetValue (n));
1246 private static Term Flsh (Domain domain, Variable vari, Term[] args)
1248 int n = args[0].Intval << args[1].Intval;
1249 return (vari == null ? new Term (n) : vari.SetValue (n));
1252 private static Term Frsh (Domain domain, Variable vari, Term[] args)
1254 int n = args[0].Intval >> args[1].Intval;
1255 return (vari == null ? new Term (n) : vari.SetValue (n));
1258 private static Term Feq (Domain domain, Variable vari, Term[] args)
1262 if (o.objval == null)
1264 for (int i = 1; i < args.Length; i++)
1265 if (args[i].objval != null || args[i].intval != o.intval)
1270 for (int i = 1; i < args.Length; i++)
1271 if (o.objval.Equals (args[i].objval))
1277 private static Term Fnoteq (Domain domain, Variable vari, Term[] args)
1279 return Feq (domain, vari, args);
1282 private static Term Flt (Domain domain, Variable vari, Term[] args)
1284 int n = args[0].Intval;
1286 for (int i = 1; i < args.Length; i++)
1288 int n1 = args[i].Intval;
1296 private static Term Fle (Domain domain, Variable vari, Term[] args)
1298 int n = args[0].Intval;
1299 for (int i = 1; i < args.Length; i++)
1301 int n1 = args[i].Intval;
1309 private static Term Fgt (Domain domain, Variable vari, Term[] args)
1311 int n = args[0].Intval;
1312 for (int i = 1; i < args.Length; i++)
1314 int n1 = args[i].Intval;
1322 private static Term Fge (Domain domain, Variable vari, Term[] args)
1324 int n = args[0].Intval;
1325 for (int i = 1; i < args.Length; i++)
1327 int n1 = args[i].Intval;
1335 private static Term Fappend (Domain domain, Variable vari, Term[] args)
1340 list = new List<Term> ();
1342 list = vari.Value.Listval;
1344 foreach (Term arg in args)
1347 list.AddRange ((List<Term>) arg.objval);
1355 result.objval = list;
1361 private static Term Fconcat (Domain domain, Variable vari, Term[] args)
1368 str = vari.Value.Strval;
1370 foreach (Term arg in args)
1373 str += (string) arg.objval;
1374 else if (arg.IsList)
1375 foreach (Term term in (List<Term>) arg.objval)
1376 str += (char) term.Intval;
1378 str += (char) arg.Intval;
1388 return vari.SetValue (str);
1391 private static Term Fnth (Domain domain, Variable vari, Term[] args)
1397 result.intval = ((string) args[1].objval)[args[0].Intval];
1398 result.objval = null;
1400 else if (args[1].IsList)
1402 result = ((List<Term>) args[1].objval)[args[0].Intval];
1405 throw new Exception ("Term is not enumelable: " + args[1]);
1409 private static Term Fcopy (Domain domain, Variable vari, Term[] args)
1414 result.objval = new List<Term> (args[0].Listval);
1418 private static Term Fins (Domain domain, Variable vari, Term[] args)
1420 Term term = vari.Value;
1424 string str = term.Strval.Insert (args[0].Intval, args[1].Strval);
1425 vari.SetValue (str);
1427 else if (vari.Value.IsList)
1428 vari.Value.Listval.InsertRange (args[0].Intval, args[1].Listval);
1430 throw new Exception ("term is not collection: " + vari.Value);
1434 private static Term Fdel (Domain domain, Variable vari, Term[] args)
1436 if (vari.Value.IsStr)
1439 = vari.Value.Strval.Remove (args[0].Intval,
1440 args[1].Intval - args[0].Intval);
1441 vari.SetValue (str);
1443 else if (vari.Value.IsList)
1444 vari.Value.Listval.RemoveRange (args[0].Intval,
1445 args[1].Intval - args[0].Intval);
1447 throw new Exception ("term is not collection: " + vari.Value);
1451 private static Term Fand (Domain domain, Variable vari, Term[] args)
1453 foreach (Term arg in args)
1454 if (! arg.Eval (domain).IsTrue)
1459 private static Term For (Domain domain, Variable vari, Term[] args)
1461 foreach (Term arg in args)
1462 if (arg.Eval (domain).IsTrue)
1467 private static Term Feval (Domain domain, Variable vari, Term[] args)
1469 return (args[0].Eval (domain));
1472 private static Term Fprogn (Domain domain, Variable vari, Term[] args)
1476 foreach (Term arg in args)
1477 result = arg.Eval (domain);
1481 private static Term Fif (Domain domain, Variable vari, Term[] args)
1483 if (args[0].Eval (domain).IsTrue)
1484 return args[1].Eval (domain);
1485 if (args.Length == 2)
1487 return args[2].Eval (domain);
1490 private static Term Fwhen (Domain domain, Variable vari, Term[] args)
1492 if (! args[0].Eval (domain).IsTrue)
1495 for (int i = 1; i < args.Length; i++)
1496 result = args[i].Eval (domain);
1500 private static Term Freturn (Domain domain, Variable vari, Term[] args)
1502 domain.ThrowReturn ();
1503 return args.Length == 0 ? Zero : args[0];
1506 private static Term Fbreak (Domain domain, Variable vari, Term[] args)
1508 domain.ThrowBreak ();
1509 return args.Length == 0 ? Zero : args[0];
1512 private static Term Floop (Domain domain, Variable vari, Term[] args)
1516 domain.Catch (CatchTag.Break);
1517 while (! domain.Thrown)
1518 foreach (Term arg in args)
1520 result = arg.Eval (domain);
1530 private static Term Fwhile (Domain domain, Variable vari, Term[] args)
1534 domain.Catch (CatchTag.Break);
1535 while (! domain.Thrown && args[0].Eval (domain).IsTrue)
1536 for (int i = 1; i < args.Length; i++)
1538 result = args[i].Eval (domain);
1548 private static Term Fcond (Domain domain, Variable vari, Term[] args)
1550 foreach (Term arg in args)
1552 List<Term> list = arg.Listval;
1553 Term result = list[0].Eval (domain);
1557 for (int i = 1; i < list.Count; i++)
1558 result = list[i].Eval (domain);
1565 private static Term Fforeach (Domain domain, Variable vari,
1568 Term result = args[0].Eval (domain);
1571 List<Term> list = result.Listval;
1572 Bindings current = domain.bindings;
1575 domain.Catch (CatchTag.Break);
1576 foreach (Term term in list)
1578 domain.Bind (vari, term);
1580 for (int i = 1; i < args.Length; i++)
1582 result = args[i].Eval (domain);
1587 domain.UnboundTo (current);
1596 private static Term Fquote (Domain domain, Variable vari, Term[] args)
1598 return new Term (args[0]);
1601 private static Term Ftype (Domain domain, Variable vari, Term[] args)
1607 if (args[0].IsSymbol)
1614 public static Term Fcatch (Domain domain, Variable vari, Term[] args)
1618 domain.Catch (new CatchTag (args[0].Symval));
1619 result = args[1].Eval (domain);
1626 public static Term Fthrow (Domain domain, Variable vari, Term[] args)
1628 domain.ThrowTag (new CatchTag (args[0].Symval));
1629 return (args.Length == 1 ? Zero : args[1]);
1632 public delegate TermValue TermParser (Domain domain, XmlNode node);
1634 public class TermType
1636 public readonly Symbol type;
1637 internal readonly TermParser parser;
1639 public TermType (Symbol type, TermParser parser)
1642 this.parser = parser;
1646 public abstract class TermValue
1648 public virtual Term Eval (Domain domain) { return new Term (this); }
1649 public virtual TermValue Clone () { return this; }
1652 private class Varref : TermValue
1654 private Symbol name;
1655 private Variable vari;
1657 public Varref (Symbol name) { this.name = name; }
1659 public override Term Eval (Domain domain)
1661 if (vari == null || vari.domain != domain)
1662 vari = domain.GetVar (name, true);
1666 internal static TermValue parser (Domain domain, XmlNode node)
1668 return new Varref ((Symbol) node.Attributes[Qvname].Value);
1671 public override string ToString ()
1673 return "<varref vname=\"" + name + "\"/>";
1677 private class Funcall : TermValue
1679 internal Function func;
1680 internal Variable vari;
1681 internal Term[] args;
1683 public Funcall (Function func, Variable vari, Term[] args)
1687 int nargs = args.Length;
1688 if (nargs < func.min_arg
1689 || (func.max_arg >= 0 && nargs > func.max_arg))
1690 throw new Exception ("Invalid number of arguments to: "
1691 + func.name + " " + nargs);
1698 internal static TermValue parser (Domain domain, XmlNode node)
1700 Symbol fname = node.Name;
1703 if (fname == Qfuncall)
1704 fname = node.Attributes[Qfname].Value;
1705 Function func = domain.GetFunc (fname);
1707 attr = node.Attributes[Qvname];
1708 vari = attr == null ? null : domain.GetVar (attr.Value, true);
1709 XmlNodeList nlist = node.ChildNodes;
1710 int nargs = nlist.Count;
1711 Term[] args = new Term[nargs];
1712 for (int i = 0; i < nargs; i++)
1713 args[i] = new Term (domain, nlist[i]);
1714 return new Funcall (func, vari, args);
1717 public override Term Eval (Domain domain)
1719 domain.DebugWrite (true, ToString ());
1721 Term result = func.Call (domain, vari, args);
1723 domain.DebugWrite (true, " ==> {0}", result.ToString ());
1727 public override TermValue Clone ()
1729 return new Funcall (func, vari, args);
1732 public override string ToString ()
1734 string str = "<" + func.name;
1736 str += " vname=\"" + vari.name + "\"";
1740 if (func is Function.SpecialForm)
1741 str += String.Format ("({0})...", args.Length);
1743 foreach (Term e in args)
1745 return (str + "</" + func.name + ">");
1752 public object objval;
1754 // <integer>...</integer>
1755 public Term (int i) { intval = i; objval = null; }
1756 // <symbol>...</symbol>
1757 public Term (Symbol name) { intval = 0; objval = name; }
1758 // <string>...</string>
1759 public Term (string str) { intval = 0; objval = str; }
1761 public Term (List<Term> list) { intval = 0; objval = list; }
1763 public Term (Term term) { intval = term.intval; objval = term.objval; }
1764 public Term (TermValue obj) { intval = 0; objval = obj; }
1766 public Term (Domain domain, XmlNode node)
1768 Symbol name = node.Name;
1770 if (name == Qinteger)
1772 intval = parse_integer (node.InnerText);
1778 if (name == Qsymbol)
1779 objval = (Symbol) node.InnerText;
1780 else if (name == Qstring)
1781 objval = node.InnerText.Clone ();
1782 else if (name == Qlist)
1784 List<Term> list = new List<Term> ();
1785 for (node = node.FirstChild; node != null;
1786 node = node.NextSibling)
1787 list.Add (new Term (domain, node));
1794 if (domain.termtypes.TryGetValue (name, out term_type))
1795 objval = term_type.parser (domain, node);
1798 Funcall funcall = (Funcall) Funcall.parser (domain, node);
1799 if (funcall.func is Function.Macro)
1801 Term result = funcall.Eval (domain);
1802 intval = result.intval;
1803 objval = result.objval;
1812 // <varref vname="VNAME"/>
1813 public Term (Domain domain, Symbol vname)
1816 objval = new Varref (vname);
1819 // <funcall fname="FNAME">...</funcall>
1820 public Term (Domain domain, Symbol fname, Term[] args)
1821 : this (domain, fname, Qnull, args) { }
1823 // <funcall fname="FNAME" vname="VNAME">...</funcall>
1824 public Term (Domain domain, Symbol fname, Symbol vname, Term[] args)
1828 Function func = domain.GetFunc (fname);
1829 Variable vari = vname == Qnull ? null : domain.GetVar (vname, true);
1830 Funcall funcall = new Funcall (func, vari, args);
1831 if (func is Function.Macro)
1833 Term result = funcall.Eval (domain);
1834 intval = result.intval;
1835 objval = result.objval;
1841 public object Objval {
1844 throw new Exception ("term is an integer: " + this);
1852 throw new Exception ("term is not integer: " + this);
1857 public string Strval {
1860 throw new Exception ("term is not string: " + this);
1861 return (string) objval;
1865 public string Symval {
1868 throw new Exception ("term is not symbol: " + this);
1869 return (Symbol) objval;
1873 public List<Term> Listval {
1876 throw new Exception ("term is not list: " + this);
1877 return (List<Term>) objval;
1881 public bool IsTrue {
1883 return (objval == null
1885 : objval is List<Term>
1886 ? (((List<Term>) objval).Count != 0)
1890 public bool IsInt { get { return (objval == null); } }
1891 public bool IsStr { get { return (objval is string); } }
1892 public bool IsSymbol { get { return (objval is Symbol); } }
1893 public bool IsList { get { return (objval is List<Term>); } }
1895 public bool IsType (Type type)
1897 return (objval == null ? type == typeof (int)
1898 : type == objval.GetType ());
1901 public Term Eval (Domain domain)
1903 if (objval == null || objval is Symbol || objval is string)
1905 if (objval is List<Term>)
1906 return new Term ((List<Term>) objval);
1907 return ((TermValue) objval).Eval (domain);
1910 public Term Clone ()
1912 if (objval == null || objval is Symbol || objval is string)
1914 if (objval is List<Term>)
1916 List<Term> list = new List<Term> ();
1917 list.InsertRange (0, ((List<Term>) objval));
1918 return new Term (list);
1920 return new Term (((TermValue) objval).Clone ());
1923 public override string ToString ()
1928 str = "<integer>" + intval + "</integer>";
1929 else if (objval is Symbol)
1930 str = "<symbol>" + objval + "</symbol>";
1931 else if (objval is string)
1932 str = "<string>" + objval + "</string>";
1933 else if (objval is List<Term>)
1936 foreach (Term e in (List<Term>) objval)
1940 else if (objval is Term)
1941 str = "<quote>" + objval + "</quote>";
1942 else if (objval is TermValue)
1943 str = ((TermValue) objval).ToString ();
1945 throw new Exception ("invalid Term object: " + objval);
1950 static private Term Zero = new Term (0);
1951 static private Term One = new Term (1);
1952 static private Term TermInt = new Term (Qinteger);
1953 static private Term TermStr = new Term (Qstring);
1954 static private Term TermSymbol = new Term (Qsymbol);
1955 static private Term TermList = new Term (Qlist);
1956 static private Term TermTerm = new Term ((Symbol) "term");
1958 internal static int parse_integer (string str)
1960 int len = str.Length;
1961 bool negative = false;
1964 return (len == 0 ? 0 : str[0] - '0');
1971 if ((c == '0' || c == '#') && str[1] == 'x')
1974 for (int idx = 2; idx < len; idx++)
1980 i = i * 16 + (c - '0');
1984 i = i * 16 + (c - 'A');
1988 i = i * 16 + (c - 'a');
1997 for (int idx = 1; idx < len; idx++)
2000 if (c < '0' || c > '9')
2002 i = i * 10 + (c - '0');
2004 return negative ? - i : i;
2007 private Term[] terms;
2009 public static Term[] ParseTerms (Domain domain, XmlNode node)
2012 for (XmlNode n = node; n != null; n = n.NextSibling)
2013 if (n.NodeType == XmlNodeType.Element)
2015 if (n.Name == Qdefun)
2016 domain.Defun (n, true);
2017 else if (n.Name == Qdefmacro)
2018 domain.Defmacro (n, true);
2019 else if (n.Name == Qdefvar)
2024 Term[] terms = new Term[nterms];
2026 for (XmlNode n = node; n != null; n = n.NextSibling)
2027 if (n.NodeType == XmlNodeType.Element)
2029 if (n.Name == Qdefun)
2030 domain.Defun (n, false);
2031 else if (n.Name == Qdefmacro)
2032 domain.Defmacro (n, false);
2033 else if (n.Name != Qdefvar)
2034 terms[i++]= new Term (domain, n);
2039 public static Term Eval (Domain domain, Term[] terms)
2041 Term result = new Term (0);
2042 foreach (Term term in terms)
2045 if (result.Objval is Funcall)
2046 while ((result = result.Eval (domain)).Objval is Funcall);
2052 public Xexpression (Domain domain, XmlNode node)
2054 terms = ParseTerms (domain, node);
2057 public Xexpression (Domain domain, string url)
2059 XmlDocument doc = new XmlDocument (Symbol.Table);
2062 using (XmlTextReader reader = new XmlTextReader (url, Symbol.Table))
2066 } while (reader.NodeType != XmlNodeType.None
2067 && (reader.NodeType != XmlNodeType.Element
2068 || reader.Name != Qexpr));
2069 if (reader.NodeType == XmlNodeType.None)
2070 throw new Exception ("Node <expr> not found");
2071 node = doc.ReadNode (reader);
2073 terms = ParseTerms (domain, node.FirstChild);
2076 public Term Eval (Domain domain)
2082 domain.Catch (CatchTag.Return);
2083 foreach (Term term in terms)
2085 result = term.Eval (domain);
2095 public override string ToString ()
2098 for (int i = 0; i < terms.Length; i++)