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 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 private static Symbol Qdefvar = "defvar";
101 private static Symbol Qvname = "vname";
102 private static Symbol Qdescription = "description";
103 private static Symbol Qrange = "range";
105 internal 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;
256 Term[] newargs = new Term[args.Length];
257 for (i = 0; i < min_arg; i++)
258 newargs[i] = args[i].Eval (domain);
260 for (i = 0; i < min_arg; i++)
261 domain.Bind (this.args[i], args[i]);
265 domain.Catch (CatchTag.Return);
266 foreach (Term term in body)
268 result = term.Eval (domain);
277 domain.UnboundTo (current);
283 internal class Lambda : Function
285 internal Variable[] args;
286 internal Term[] body;
288 public Lambda (Domain domain, XmlNode node)
290 parse_head (domain, node, out name, out min_arg, out max_arg,
294 public Lambda (Domain domain, Symbol name, Symbol[] args)
304 for (i = 0; i < args.Length; i++, nfixed++)
305 if (args[i] == Qoptional || args[i] == Qrest)
309 if (args[i] == Qoptional)
311 for (i++; i < args.Length; i++, noptional++)
312 if (args[i] == Qrest)
319 max_arg = nfixed + noptional + nrest;
320 this.args = new Variable[max_arg];
322 for (i = j = 0; j < this.args.Length; i++)
323 if (args[i] != Qoptional || args[i] != Qrest)
324 this.args[j++] = domain.Defvar (args[i]);
328 min_arg = max_arg = 0;
332 public void SetBody (Domain domain, XmlNode node)
334 parse_body (domain, node, out body);
337 public void SetBody (Term[] body)
342 public override Term Call (Domain domain, Variable vari, Term[] args)
344 Bindings current = domain.bindings;
351 Term[] newargs = new Term[args.Length];
352 for (i = 0; i < min_arg; i++)
353 newargs[i] = args[i].Eval (domain);
356 for (i = 0; i < min_arg; i++)
357 domain.Bind (this.args[i], args[i]);
361 domain.Catch (CatchTag.Return);
362 foreach (Term term in body)
364 result = term.Eval (domain);
373 domain.UnboundTo (current);
380 public class Variable
382 public Domain domain;
383 public readonly Symbol name;
385 protected Term default_val;
389 public Variable (Domain domain, Symbol name, Term val)
391 this.domain = domain;
397 public virtual bool ValueP (Term val) { return true; }
399 public Variable Clone (Domain domain)
401 Variable v = new Variable (domain, name, val);
403 v.default_val = default_val;
412 if (! ValueP (value))
413 throw new Exception ("Invalid value: " + value);
418 public Term SetValue (int i)
425 public Term SetValue (string s)
431 public Term DefaultValue
433 get { return default_val; }
435 if (! ValueP (value))
436 throw new Exception ("Invalid value: " + value);
441 public virtual object Range
443 get { return range; }
444 set { range = value; }
447 public override string ToString () { return name + "(" + val + ")"; }
449 public class Int : Variable
453 private static bool SubsetP (int[] r1, int[] r2)
457 for (int i = 0; i < r1.Length; i += 2)
460 for (j = 0; j < r2.Length; j += 2)
461 if (r2[j] <= r1[i] && r2[j + 1] >= r1[i + 1])
469 private static bool SubsetP (int val, int[] r)
473 for (int i = 0; i < r.Length; i += 2)
474 if (r[i] <= val && r[i + 1] >= val)
479 public Int (Domain domain, Symbol name, string description,
480 int value, int[] range)
481 : base (domain, name, new Term (value))
483 if (! SubsetP (value, range))
484 throw new Exception ("Invalid value: " + value);
490 public override bool ValueP (Term term)
494 return SubsetP (term.Intval, range);
497 public override object Range {
498 get { return range; }
500 int[] r = (int[]) value;
501 if (! SubsetP (r, range)
502 || ! SubsetP (val.Intval, r)
503 || ! SubsetP (default_val.Intval, r))
504 throw new Exception ("Invalid range");
510 public class Str : Variable
512 public string[] range;
514 private static bool SubsetP (string[] r1, string[] r2)
518 foreach (string s in r1)
519 if (! SubsetP (s, r2))
524 private static bool SubsetP (string str, string[] r)
528 foreach (string s in r)
534 public Str (Domain domain, Symbol name, string description,
535 string value, string[] range)
536 : base (domain, name, new Term (value))
538 if (! SubsetP (value, range))
539 throw new Exception ("Invalid value: " + value);
545 public override bool ValueP (Term term)
547 if (! (term.objval is string))
549 return SubsetP (term.Strval, range);
552 public override object Range {
553 get { return range; }
555 string[] r = (string[]) value;
556 if (! SubsetP (r, range)
557 || ! SubsetP (val.Strval, r)
558 || ! SubsetP (default_val.Strval, r))
559 throw new Exception ("Invalid range");
565 public class Sym : Variable
567 public Symbol[] range;
569 private static bool SubsetP (Symbol[] r1, Symbol[] r2)
573 foreach (Symbol n in r1)
574 if (! SubsetP (n, r2))
579 private static bool SubsetP (Symbol name, Symbol[] r)
583 foreach (Symbol n in r)
589 public Sym (Domain domain, Symbol name, string description,
590 Symbol value, Symbol[] range)
591 : base (domain, name, new Term (value))
593 if (! SubsetP (value, range))
594 throw new Exception ("Invalid value: " + value);
600 public override bool ValueP (Term term)
602 if (! (term.objval is Symbol))
604 return SubsetP (term.Symval, range);
607 public override object Range {
608 get { return range; }
610 Symbol[] r = (Symbol[]) value;
611 if (! SubsetP (r, range)
612 || ! SubsetP (val.Symval, r)
613 || ! SubsetP (default_val.Symval, r))
614 throw new Exception ("Invalid range");
621 internal class Bindings
623 private Variable vari;
624 private Term old_value;
625 private Bindings next;
627 private Bindings (Variable vari)
630 old_value = vari.Value;
633 public static Bindings Bind (Bindings bindings, Variable vari, Term val)
635 Bindings b = new Bindings (vari);
642 internal Bindings UnboundTo (Bindings boundary)
644 for (Bindings b = this; b != boundary; b = b.next)
645 b.vari.Value = b.old_value;
649 public override string ToString ()
651 string str = "(bindings";
652 for (Bindings b = this; b != null; b = b.next)
653 str += " " + vari.name + "=" + b.old_value;
659 internal class ThrowException : Exception
664 public ThrowException (Symbol tag, object value) : base ()
672 internal class CatchTag : IEquatable<CatchTag>
676 public CatchTag (Symbol name) { val = name.name; }
677 private CatchTag (int i) { val = i; }
679 public static CatchTag Return = new CatchTag (0);
680 public static CatchTag Break = new CatchTag (1);
682 public static bool operator== (CatchTag t1, CatchTag t2)
683 { return t1.val == t2.val; }
685 public static bool operator!= (CatchTag t1, CatchTag t2)
686 { return t1.val != t2.val; }
688 public bool Equals (CatchTag tag) { return this.val == tag.val; }
689 public override bool Equals (object val) { return this.val == val; }
691 public override int GetHashCode () { return val.GetHashCode (); }
697 public object context;
698 public int depth = 0;
700 internal Dictionary<Symbol, TermType> termtypes
701 = new Dictionary<Symbol, TermType> ();
702 internal Dictionary<Symbol, Function> functions
703 = new Dictionary<Symbol, Function> ();
704 internal Dictionary<Symbol, Variable> variables
705 = new Dictionary<Symbol, Variable> ();
706 internal Bindings bindings;
707 private Stack<CatchTag> catch_stack = new Stack<CatchTag> ();
708 private int catch_count = 0;
710 internal Domain (Symbol name) { this.name = name; }
712 public Domain (Symbol name, object context)
713 : this (name, basic, context) { }
715 public Domain (Symbol name, Domain parent, object context) : this (name)
717 termtypes = new Dictionary<Symbol, TermType> (parent.termtypes);
718 functions = new Dictionary<Symbol, Function> (parent.functions);
719 variables = new Dictionary<Symbol, Variable> (parent.variables);
720 this.context = context;
723 internal void Bind (Variable vari, Term value)
725 bindings = Bindings.Bind (bindings, vari, value);
728 internal void UnboundTo (Bindings boundary)
730 if (bindings != null)
731 bindings = bindings.UnboundTo (boundary);
734 internal void Catch (CatchTag tag)
736 catch_stack.Push (tag);
740 internal void Uncatch ()
743 if (catch_count > catch_stack.Count)
748 get { return catch_count < catch_stack.Count; }
751 internal void ThrowReturn ()
753 foreach (CatchTag tag in catch_stack)
756 if (tag == CatchTag.Return)
761 internal void ThrowBreak ()
763 if (catch_stack.Peek () != CatchTag.Break)
764 throw new Exception ("No outer loop to break");
768 internal void ThrowTag (CatchTag tag)
770 foreach (CatchTag elt in catch_stack)
778 public void DefTerm (Symbol name, TermParser parser)
780 if (termtypes.ContainsKey (name)
781 || functions.ContainsKey (name))
782 throw new Exception ("already defined: " + name);
783 termtypes[name] = new TermType (name, parser);
786 public void DefSubr (Builtin builtin, string str, bool setvar,
787 int min_arg, int max_arg, params string[] aliases)
790 if (termtypes.ContainsKey (name))
791 throw new Exception ("already defined as termtype: " + name);
792 Function func = new Function.Subroutine (builtin, name, setvar,
794 functions[name] = func;
795 foreach (string a in aliases)
796 functions[(Symbol) a] = func;
799 public void DefSpecial (Builtin builtin, string str,
800 int min_arg, int max_arg,
801 params string[] aliases)
804 if (termtypes.ContainsKey (name))
805 throw new Exception ("already defined as termtype: " + name);
806 Function func = new Function.SpecialForm (builtin, name,
808 functions[name] = func;
809 foreach (string a in aliases)
810 functions[(Symbol) a] = func;
813 public void DefAlias (string alias, string str)
815 functions[(Symbol) alias] = functions[(Symbol) str];
818 public void Defun (Symbol name, Symbol[] args, Term[] body,
823 if (termtypes.ContainsKey (name))
824 throw new Exception ("already defined as termtype: " + name);
825 if (prototype || ! functions.TryGetValue (name, out func))
827 func = new Function.Lambda (this, name, args);
828 functions[name] = func;
831 ((Function.Lambda) func).SetBody (body);
834 public void Defun (XmlNode node, bool prototype)
836 Symbol name = node.Attributes[Qfname].Value;
837 if (termtypes.ContainsKey (name))
838 throw new Exception ("already defined as termtype: " + name);
841 if (prototype || ! functions.TryGetValue (name, out func))
843 func = new Function.Lambda (this, node);
844 functions[name] = func;
847 ((Function.Lambda) func).SetBody (this, node);
850 public void Defun (Function func)
852 functions[func.name] = func;
855 public void Defmacro (XmlNode node, bool prototype)
857 Symbol name = node.Attributes[Qfname].Value;
858 if (termtypes.ContainsKey (name))
859 throw new Exception ("already defined as termtype: " + name);
862 if (prototype || ! functions.TryGetValue (name, out func))
864 func = new Function.Macro (this, node);
865 functions[name] = func;
868 ((Function.Macro) func).SetBody (this, node);
871 public Variable Defvar (XmlNode node)
873 Symbol name = node.Attributes[0].Value;
877 node = node.FirstChild;
878 if (node != null && node.Name == Qdescription)
880 desc = node.InnerText;
881 node = node.NextSibling;
887 Symbol type = node.Name;
888 XmlNodeList range_list = null;
890 string val = node.InnerText;
892 node = node.NextSibling;
895 range_list = node.ChildNodes;
896 nranges = range_list.Count;
899 if (type == Qinteger)
901 int intval = parse_integer (val);
903 if (range_list != null)
905 range = new int[nranges * 2];
906 for (int i = 0; i < nranges; i++)
908 XmlNode n = range_list[i];
909 if (n.Name == Qrange)
912 = parse_integer (n.FirstChild.InnerText);
914 = parse_integer (n.LastChild.InnerText);
920 = parse_integer (n.FirstChild.InnerText);
925 if (variables.TryGetValue (name, out vari))
927 if (! (vari is Variable.Int))
928 throw new Exception ("Inalid value");
929 vari = (Variable) vari.Clone (this);
930 Term v = new Term (intval);
932 vari.DefaultValue = v;
937 vari = new Variable.Int (this, name, desc, intval, range);
939 else if (type == Qstring)
941 string[] range = null;
942 if (range_list != null)
944 range = new string[nranges];
945 for (int i = 0; i < nranges; i++)
946 range[i] = range_list[i].FirstChild.InnerText;
949 if (variables.TryGetValue (name, out vari))
951 if (! (vari is Variable.Str))
952 throw new Exception ("Invalid value");
953 vari = (Variable) vari.Clone (this);
954 Term v = new Term (val);
956 vari.DefaultValue = v;
961 vari = new Variable.Str (this, name, desc, val, range);
963 else if (type == Qsymbol)
965 Symbol[] range = null;
966 if (range_list != null)
968 range = new Symbol[nranges];
969 for (int i = 0; i < nranges; i++)
970 range[i] = range_list[i].FirstChild.InnerText;
973 if (variables.TryGetValue (name, out vari))
975 if (! (vari is Variable.Sym))
976 throw new Exception ("Invalid value");
977 vari = (Variable) vari.Clone (this);
978 Term v = new Term (val);
980 vari.DefaultValue = v;
985 vari = new Variable.Sym (this, name, desc, val, range);
988 throw new Exception ("Unknown type: " + type);
992 if (variables.TryGetValue (name, out vari))
993 vari = (Variable) vari.Clone (this);
995 vari = new Variable (this, name, Zero);
997 variables[name] = vari;
1001 public Variable Defvar (Variable vari)
1003 vari = vari.Clone (this);
1004 variables[vari.name] = vari;
1008 internal Variable Defvar (Symbol name)
1010 Variable vari = new Variable (this, name, Zero);
1011 variables[name] = vari;
1015 internal Function GetFunc (Symbol name)
1019 if (! functions.TryGetValue (name, out func))
1020 throw new Exception ("Unknown function: " + name);
1024 public bool CopyFunc (Domain domain, Symbol name)
1026 Function func = GetFunc (name);
1028 domain.functions[name] = func;
1032 public void CopyFunc (Domain domain)
1034 foreach (KeyValuePair<Symbol, Function> kv in functions)
1035 domain.functions[kv.Key] = kv.Value;
1038 public Variable GetVar (Symbol name, bool create)
1042 if (! variables.TryGetValue (name, out vari))
1046 variables[name] = vari = new Variable (this, name, Zero);
1051 public override string ToString ()
1053 string str = "<(functions";
1054 foreach (KeyValuePair<Symbol, Function> kv in functions)
1055 str += " " + kv.Key;
1056 str += ") (variabls";
1057 foreach (KeyValuePair<Symbol, Variable> kv in variables)
1058 str += " " + kv.Value;
1060 if (bindings != null)
1061 str += " " + bindings;
1062 if (context != null)
1063 str += " (" + context + ")";
1068 internal void DebugWrite (bool head, string fmt, params string[] arg)
1070 if (debug_level > depth)
1074 Console.WriteLine ();
1075 for (int i = 0; i < depth; i++)
1076 Console.Write (" ");
1078 Console.Write (fmt, arg);
1082 public object SaveValues ()
1084 Dictionary<Variable,Term> values = new Dictionary<Variable,Term> ();
1086 foreach (KeyValuePair<Symbol,Variable> kv in variables)
1087 values[kv.Value] = kv.Value.Value.Clone ();
1091 public void RestoreValues (object values)
1093 foreach (KeyValuePair<Variable,Term> kv
1094 in (Dictionary<Variable,Term>) values)
1095 kv.Key.Value = kv.Value;
1099 public delegate Term Builtin (Domain domain, Variable vari, Term[] args);
1101 private static Domain basic = new Domain ("basic");
1103 static Xexpression ()
1105 basic.DefTerm ("funcall", Funcall.parser);
1106 basic.DefTerm ("varref", Varref.parser);
1108 basic.DefSubr (Fset, "set", true, 1, 1, "=");
1109 basic.DefSubr (Fnot, "not", false, 1, 1, "!");
1110 basic.DefSubr (Fadd, "add", true, 1, -1, "+");
1111 basic.DefSubr (Fmul, "mul", true, 1, -1, "*");
1112 basic.DefSubr (Fsub, "sub", true, 1, -1, "-");
1113 basic.DefSubr (Fdiv, "div", true, 1, -1, "/");
1114 basic.DefSubr (Fmod, "mod", true, 1, 2, "%");
1115 basic.DefSubr (Flogior, "logior", true, 1, -1, "|");
1116 basic.DefSubr (Flogand, "logand", true, 1, -1, "&");
1117 basic.DefSubr (Flsh, "lsh", true, 1, 2, "<<");
1118 basic.DefSubr (Frsh, "rsh", true, 1, 2, ">>");
1119 basic.DefSubr (Feq, "eq", false, 2, -1, "==");
1120 basic.DefSubr (Fnoteq, "noteq", false, 2, 2, "!=");
1121 basic.DefSubr (Flt, "lt", false, 2, -1, "<");
1122 basic.DefSubr (Fle, "le", false, 2, -1, "<=");
1123 basic.DefSubr (Fgt, "gt", false, 2, -1, ">");
1124 basic.DefSubr (Fge, "ge", false, 2, -1, ">=");
1125 basic.DefSubr (Fappend, "append", true, 0, -1);
1126 basic.DefSubr (Fconcat, "concat", true, 0, -1);
1127 basic.DefSubr (Fnth, "nth", false, 2, 2);
1128 basic.DefSubr (Fcopy, "copy", false, 1, 1);
1129 basic.DefSubr (Fins, "ins", true, 2, 2);
1130 basic.DefSubr (Fdel, "del", true, 2, 2);
1131 basic.DefSubr (Feval, "eval", false, 1, 1);
1132 basic.DefSubr (Fbreak, "break", false, 0, 1);
1133 basic.DefSubr (Freturn, "return", false, 0, 1);
1135 basic.DefSpecial (Fand, "and", 1, -1, "&&");
1136 basic.DefSpecial (For, "or", 1, -1, "||");
1137 basic.DefSpecial (Fprogn, "progn", 0, -1, "expr");
1138 basic.DefSpecial (Fif, "if", 2, 3);
1139 basic.DefSpecial (Fwhen, "when", 1, -1);
1140 basic.DefSpecial (Floop, "loop", 1, -1);
1141 basic.DefSpecial (Fwhile, "while", 1, -1);
1142 basic.DefSpecial (Fcond, "cond", 1, -1);
1143 basic.DefSpecial (Fforeach, "foreach", 2, -1);
1144 basic.DefSpecial (Fquote, "quote", 1, 1);
1145 basic.DefSpecial (Ftype, "type", 1, 1);
1146 basic.DefSpecial (Fcatch, "catch", 2, 2);
1147 basic.DefSpecial (Fthrow, "throw", 1, 2);
1150 private static Term Fset (Domain domain, Variable vari, Term[] args)
1152 vari.Value = args[0];
1156 private static Term Fnot (Domain domain, Variable vari, Term[] args)
1158 return args[0].IsTrue ? Zero : One;
1161 private static Term Fadd (Domain domain, Variable vari, Term[] args)
1163 int n = vari == null ? 0 : vari.Value.Intval;
1165 foreach (Term arg in args)
1167 return (vari == null ? new Term (n) : vari.SetValue (n));
1170 private static Term Fmul (Domain domain, Variable vari, Term[] args)
1172 int n = vari == null ? 1 : vari.Value.Intval;
1173 foreach (Term arg in args)
1175 return (vari == null ? new Term (n) : vari.SetValue (n));
1178 private static Term Fsub (Domain domain, Variable vari, Term[] args)
1189 n = vari.Value.Intval;
1192 while (i < args.Length)
1193 n -= args[i++].Intval;
1194 return (vari == null ? new Term (n) : vari.SetValue (n));
1197 private static Term Fdiv (Domain domain, Variable vari, Term[] args)
1208 n = vari.Value.Intval;
1211 while (i < args.Length)
1212 n /= args[i++].Intval;
1213 return (vari == null ? new Term (n) : vari.SetValue (n));
1216 private static Term Fmod (Domain domain, Variable vari, Term[] args)
1218 int n = args[0].Intval % args[1].Intval;
1220 return (vari == null ? new Term (n) : vari.SetValue (n));
1223 private static Term Flogior (Domain domain, Variable vari, Term[] args)
1225 int n = vari == null ? 0 : vari.Value.Intval;
1226 foreach (Term arg in args)
1228 return (vari == null ? new Term (n) : vari.SetValue (n));
1231 private static Term Flogand (Domain domain, Variable vari, Term[] args)
1242 n = vari.Value.Intval;
1245 while (i < args.Length)
1246 n &= args[i++].Intval;
1247 return (vari == null ? new Term (n) : vari.SetValue (n));
1250 private static Term Flsh (Domain domain, Variable vari, Term[] args)
1252 int n = args[0].Intval << args[1].Intval;
1253 return (vari == null ? new Term (n) : vari.SetValue (n));
1256 private static Term Frsh (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 Feq (Domain domain, Variable vari, Term[] args)
1266 if (o.objval == null)
1268 for (int i = 1; i < args.Length; i++)
1269 if (args[i].objval != null || args[i].intval != o.intval)
1274 for (int i = 1; i < args.Length; i++)
1275 if (o.objval.Equals (args[i].objval))
1281 private static Term Fnoteq (Domain domain, Variable vari, Term[] args)
1283 return Feq (domain, vari, args);
1286 private static Term Flt (Domain domain, Variable vari, Term[] args)
1288 int n = args[0].Intval;
1290 for (int i = 1; i < args.Length; i++)
1292 int n1 = args[i].Intval;
1300 private static Term Fle (Domain domain, Variable vari, Term[] args)
1302 int n = args[0].Intval;
1303 for (int i = 1; i < args.Length; i++)
1305 int n1 = args[i].Intval;
1313 private static Term Fgt (Domain domain, Variable vari, Term[] args)
1315 int n = args[0].Intval;
1316 for (int i = 1; i < args.Length; i++)
1318 int n1 = args[i].Intval;
1326 private static Term Fge (Domain domain, Variable vari, Term[] args)
1328 int n = args[0].Intval;
1329 for (int i = 1; i < args.Length; i++)
1331 int n1 = args[i].Intval;
1339 private static Term Fappend (Domain domain, Variable vari, Term[] args)
1344 list = new List<Term> ();
1346 list = vari.Value.Listval;
1348 foreach (Term arg in args)
1351 list.AddRange ((List<Term>) arg.objval);
1359 result.objval = list;
1365 private static Term Fconcat (Domain domain, Variable vari, Term[] args)
1372 str = vari.Value.Strval;
1374 foreach (Term arg in args)
1377 str += (string) arg.objval;
1378 else if (arg.IsList)
1379 foreach (Term term in (List<Term>) arg.objval)
1380 str += (char) term.Intval;
1382 str += (char) arg.Intval;
1392 return vari.SetValue (str);
1395 private static Term Fnth (Domain domain, Variable vari, Term[] args)
1401 result.intval = ((string) args[1].objval)[args[0].Intval];
1402 result.objval = null;
1404 else if (args[1].IsList)
1406 result = ((List<Term>) args[1].objval)[args[0].Intval];
1409 throw new Exception ("Term is not enumelable: " + args[1]);
1413 private static Term Fcopy (Domain domain, Variable vari, Term[] args)
1418 result.objval = new List<Term> (args[0].Listval);
1422 private static Term Fins (Domain domain, Variable vari, Term[] args)
1424 Term term = vari.Value;
1428 string str = term.Strval.Insert (args[0].Intval, args[1].Strval);
1429 vari.SetValue (str);
1431 else if (vari.Value.IsList)
1432 vari.Value.Listval.InsertRange (args[0].Intval, args[1].Listval);
1434 throw new Exception ("term is not collection: " + vari.Value);
1438 private static Term Fdel (Domain domain, Variable vari, Term[] args)
1440 if (vari.Value.IsStr)
1443 = vari.Value.Strval.Remove (args[0].Intval,
1444 args[1].Intval - args[0].Intval);
1445 vari.SetValue (str);
1447 else if (vari.Value.IsList)
1448 vari.Value.Listval.RemoveRange (args[0].Intval,
1449 args[1].Intval - args[0].Intval);
1451 throw new Exception ("term is not collection: " + vari.Value);
1455 private static Term Fand (Domain domain, Variable vari, Term[] args)
1457 foreach (Term arg in args)
1458 if (! arg.Eval (domain).IsTrue)
1463 private static Term For (Domain domain, Variable vari, Term[] args)
1465 foreach (Term arg in args)
1466 if (arg.Eval (domain).IsTrue)
1471 private static Term Feval (Domain domain, Variable vari, Term[] args)
1473 return (args[0].Eval (domain));
1476 private static Term Fprogn (Domain domain, Variable vari, Term[] args)
1480 foreach (Term arg in args)
1481 result = arg.Eval (domain);
1485 private static Term Fif (Domain domain, Variable vari, Term[] args)
1487 if (args[0].Eval (domain).IsTrue)
1488 return args[1].Eval (domain);
1489 if (args.Length == 2)
1491 return args[2].Eval (domain);
1494 private static Term Fwhen (Domain domain, Variable vari, Term[] args)
1496 if (! args[0].Eval (domain).IsTrue)
1499 for (int i = 1; i < args.Length; i++)
1500 result = args[i].Eval (domain);
1504 private static Term Freturn (Domain domain, Variable vari, Term[] args)
1506 domain.ThrowReturn ();
1507 return args.Length == 0 ? Zero : args[0];
1510 private static Term Fbreak (Domain domain, Variable vari, Term[] args)
1512 domain.ThrowBreak ();
1513 return args.Length == 0 ? Zero : args[0];
1516 private static Term Floop (Domain domain, Variable vari, Term[] args)
1520 domain.Catch (CatchTag.Break);
1521 while (! domain.Thrown)
1522 foreach (Term arg in args)
1524 result = arg.Eval (domain);
1534 private static Term Fwhile (Domain domain, Variable vari, Term[] args)
1538 domain.Catch (CatchTag.Break);
1539 while (! domain.Thrown && args[0].Eval (domain).IsTrue)
1540 for (int i = 1; i < args.Length; i++)
1542 result = args[i].Eval (domain);
1552 private static Term Fcond (Domain domain, Variable vari, Term[] args)
1554 foreach (Term arg in args)
1556 List<Term> list = arg.Listval;
1557 Term result = list[0].Eval (domain);
1561 for (int i = 1; i < list.Count; i++)
1562 result = list[i].Eval (domain);
1569 private static Term Fforeach (Domain domain, Variable vari,
1572 Term result = args[0].Eval (domain);
1575 List<Term> list = result.Listval;
1576 Bindings current = domain.bindings;
1579 domain.Catch (CatchTag.Break);
1580 foreach (Term term in list)
1582 domain.Bind (vari, term);
1584 for (int i = 1; i < args.Length; i++)
1586 result = args[i].Eval (domain);
1591 domain.UnboundTo (current);
1600 private static Term Fquote (Domain domain, Variable vari, Term[] args)
1602 return new Term (args[0]);
1605 private static Term Ftype (Domain domain, Variable vari, Term[] args)
1611 if (args[0].IsSymbol)
1618 public static Term Fcatch (Domain domain, Variable vari, Term[] args)
1622 domain.Catch (new CatchTag (args[0].Symval));
1623 result = args[1].Eval (domain);
1630 public static Term Fthrow (Domain domain, Variable vari, Term[] args)
1632 domain.ThrowTag (new CatchTag (args[0].Symval));
1633 return (args.Length == 1 ? Zero : args[1]);
1636 public delegate TermValue TermParser (Domain domain, XmlNode node);
1638 public class TermType
1640 public readonly Symbol type;
1641 internal readonly TermParser parser;
1643 public TermType (Symbol type, TermParser parser)
1646 this.parser = parser;
1650 public abstract class TermValue
1652 public virtual Term Eval (Domain domain) { return new Term (this); }
1653 public virtual TermValue Clone () { return this; }
1656 private class Varref : TermValue
1658 private Symbol name;
1659 private Variable vari;
1661 public Varref (Symbol name) { this.name = name; }
1663 public override Term Eval (Domain domain)
1665 if (vari == null || vari.domain != domain)
1666 vari = domain.GetVar (name, true);
1670 internal static TermValue parser (Domain domain, XmlNode node)
1672 return new Varref ((Symbol) node.Attributes[Qvname].Value);
1675 public override string ToString ()
1677 return "<varref vname=\"" + name + "\"/>";
1681 private class Funcall : TermValue
1683 internal Function func;
1684 internal Variable vari;
1685 internal Term[] args;
1687 public Funcall (Function func, Variable vari, Term[] args)
1691 int nargs = args.Length;
1692 if (nargs < func.min_arg
1693 || (func.max_arg >= 0 && nargs > func.max_arg))
1694 throw new Exception ("Invalid number of arguments to: "
1695 + func.name + " " + nargs);
1702 internal static TermValue parser (Domain domain, XmlNode node)
1704 Symbol fname = node.Name;
1707 if (fname == Qfuncall)
1708 fname = node.Attributes[Qfname].Value;
1709 Function func = domain.GetFunc (fname);
1711 attr = node.Attributes[Qvname];
1712 vari = attr == null ? null : domain.GetVar (attr.Value, true);
1713 XmlNodeList nlist = node.ChildNodes;
1714 int nargs = nlist.Count;
1715 Term[] args = new Term[nargs];
1716 for (int i = 0; i < nargs; i++)
1717 args[i] = new Term (domain, nlist[i]);
1718 return new Funcall (func, vari, args);
1721 public override Term Eval (Domain domain)
1723 domain.DebugWrite (true, ToString ());
1725 Term result = func.Call (domain, vari, args);
1727 domain.DebugWrite (true, " ==> {0}", result.ToString ());
1731 public override TermValue Clone ()
1733 return new Funcall (func, vari, args);
1736 public override string ToString ()
1738 string str = "<" + func.name;
1740 str += " vname=\"" + vari.name + "\"";
1744 if (func is Function.SpecialForm)
1745 str += String.Format ("({0})...", args.Length);
1747 foreach (Term e in args)
1749 return (str + "</" + func.name + ">");
1756 public object objval;
1758 // <integer>...</integer>
1759 public Term (int i) { intval = i; objval = null; }
1760 // <symbol>...</symbol>
1761 public Term (Symbol name) { intval = 0; objval = name; }
1762 // <string>...</string>
1763 public Term (string str) { intval = 0; objval = str; }
1765 public Term (List<Term> list) { intval = 0; objval = list; }
1767 public Term (Term term) { intval = term.intval; objval = term.objval; }
1768 public Term (TermValue obj) { intval = 0; objval = obj; }
1770 public Term (Domain domain, XmlNode node)
1772 Symbol name = node.Name;
1774 if (name == Qinteger)
1776 intval = parse_integer (node.InnerText);
1782 if (name == Qsymbol)
1783 objval = (Symbol) node.InnerText;
1784 else if (name == Qstring)
1785 objval = node.InnerText.Clone ();
1786 else if (name == Qlist)
1788 List<Term> list = new List<Term> ();
1789 for (node = node.FirstChild; node != null;
1790 node = node.NextSibling)
1791 list.Add (new Term (domain, node));
1798 if (domain.termtypes.TryGetValue (name, out term_type))
1799 objval = term_type.parser (domain, node);
1801 objval = Funcall.parser (domain, node);
1806 // <varref vname="VNAME"/>
1807 public Term (Domain domain, Symbol vname)
1810 objval = new Varref (vname);
1813 // <funcall fname="FNAME">...</funcall>
1814 public Term (Domain domain, Symbol fname, Term[] args)
1815 : this (domain, fname, Qnull, args) { }
1817 // <funcall fname="FNAME" vname="VNAME">...</funcall>
1818 public Term (Domain domain, Symbol fname, Symbol vname, Term[] args)
1822 Function func = domain.GetFunc (fname);
1823 Variable vari = vname == Qnull ? null : domain.GetVar (vname, true);
1824 objval = new Funcall (func, vari, args);
1827 public object Objval {
1830 throw new Exception ("term is an integer: " + this);
1838 throw new Exception ("term is not integer: " + this);
1843 public string Strval {
1846 throw new Exception ("term is not string: " + this);
1847 return (string) objval;
1851 public string Symval {
1854 throw new Exception ("term is not symbol: " + this);
1855 return (Symbol) objval;
1859 public List<Term> Listval {
1862 throw new Exception ("term is not list: " + this);
1863 return (List<Term>) objval;
1867 public bool IsTrue {
1869 return (objval == null
1871 : objval is List<Term>
1872 ? (((List<Term>) objval).Count != 0)
1876 public bool IsInt { get { return (objval == null); } }
1877 public bool IsStr { get { return (objval is string); } }
1878 public bool IsSymbol { get { return (objval is Symbol); } }
1879 public bool IsList { get { return (objval is List<Term>); } }
1881 public bool IsType (Type type)
1883 return (objval == null ? type == typeof (int)
1884 : type == objval.GetType ());
1887 public Term Eval (Domain domain)
1889 if (objval == null || objval is Symbol || objval is string)
1891 if (objval is List<Term>)
1892 return new Term ((List<Term>) objval);
1893 return ((TermValue) objval).Eval (domain);
1896 public Term Clone ()
1898 if (objval == null || objval is Symbol || objval is string)
1900 if (objval is List<Term>)
1902 List<Term> list = new List<Term> ();
1903 list.InsertRange (0, ((List<Term>) objval));
1904 return new Term (list);
1906 return new Term (((TermValue) objval).Clone ());
1909 public override string ToString ()
1914 str = "<integer>" + intval + "</integer>";
1915 else if (objval is Symbol)
1916 str = "<symbol>" + objval + "</symbol>";
1917 else if (objval is string)
1918 str = "<string>" + objval + "</string>";
1919 else if (objval is List<Term>)
1922 foreach (Term e in (List<Term>) objval)
1926 else if (objval is Term)
1927 str = "<quote>" + objval + "</quote>";
1928 else if (objval is TermValue)
1929 str = ((TermValue) objval).ToString ();
1931 throw new Exception ("invalid Term object: " + objval);
1936 static private Term Zero = new Term (0);
1937 static private Term One = new Term (1);
1938 static private Term TermInt = new Term (Qinteger);
1939 static private Term TermStr = new Term (Qstring);
1940 static private Term TermSymbol = new Term (Qsymbol);
1941 static private Term TermList = new Term (Qlist);
1942 static private Term TermTerm = new Term ((Symbol) "term");
1944 internal static int parse_integer (string str)
1946 int len = str.Length;
1947 bool negative = false;
1950 return (len == 0 ? 0 : str[0] - '0');
1957 if ((c == '0' || c == '#') && str[1] == 'x')
1960 for (int idx = 2; idx < len; idx++)
1966 i = i * 16 + (c - '0');
1970 i = i * 16 + (c - 'A');
1974 i = i * 16 + (c - 'a');
1983 for (int idx = 1; idx < len; idx++)
1986 if (c < '0' || c > '9')
1988 i = i * 10 + (c - '0');
1990 return negative ? - i : i;
1993 private Term[] terms;
1995 public static Term[] ParseTerms (Domain domain, XmlNode node)
1998 for (XmlNode n = node; n != null; n = n.NextSibling)
1999 if (n.NodeType == XmlNodeType.Element)
2001 if (n.Name == Qdefun)
2002 domain.Defun (n, true);
2003 else if (n.Name == Qdefvar)
2008 Term[] terms = new Term[nterms];
2010 for (XmlNode n = node; n != null; n = n.NextSibling)
2011 if (n.NodeType == XmlNodeType.Element)
2013 if (n.Name == Qdefun)
2014 domain.Defun (n, false);
2015 else if (n.Name != Qdefvar)
2016 terms[i++]= new Term (domain, n);
2021 public static Term Eval (Domain domain, Term[] terms)
2023 Term result = new Term (0);
2024 foreach (Term term in terms)
2027 if (result.Objval is Funcall)
2028 while ((result = result.Eval (domain)).Objval is Funcall);
2034 public Xexpression (Domain domain, XmlNode node)
2036 terms = ParseTerms (domain, node);
2039 public Xexpression (Domain domain, string url)
2041 XmlDocument doc = new XmlDocument (Symbol.Table);
2044 using (XmlTextReader reader = new XmlTextReader (url, Symbol.Table))
2048 } while (reader.NodeType != XmlNodeType.None
2049 && (reader.NodeType != XmlNodeType.Element
2050 || reader.Name != Qexpr));
2051 if (reader.NodeType == XmlNodeType.None)
2052 throw new Exception ("Node <expr> not found");
2053 node = doc.ReadNode (reader);
2055 terms = ParseTerms (domain, node.FirstChild);
2058 public Term Eval (Domain domain)
2064 domain.Catch (CatchTag.Return);
2065 foreach (Term term in terms)
2067 result = term.Eval (domain);
2077 public override string ToString ()
2080 for (int i = 0; i < terms.Length; i++)