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 Name : IEquatable<Name>
15 private static NameTable nt = new NameTable ();
19 public Name (string str)
24 public static implicit operator Name (string str)
26 return new Name (str);
29 public static implicit operator string (Name name)
34 public static bool operator== (Name n1, Name n2)
36 return (object) n1.name == (object) n2.name;
39 public static bool operator!= (Name n1, Name n2)
41 return (object) n1.name != (object) n2.name;
44 public static bool operator== (Name n1, string n2)
46 return (object) n1.name == (object) n2;
49 public static bool operator!= (Name n1, string n2)
51 return (object) n1.name != (object) n2;
54 public static bool operator== (string n1, Name n2)
56 return (object) n1 == (object) n2.name;
59 public static bool operator!= (string n1, Name n2)
61 return (object) n1 != (object) n2.name;
64 public bool Equals (Name 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 Name Nexpr = "expr";
86 private static Name Nfuncall = "funcall";
87 private static Name Nvariable = "variable";
88 private static Name Ninteger = "integer";
89 private static Name Nstring = "string";
90 private static Name Nsymbol = "symbol";
91 private static Name Nlist = "list";
93 private static Name Ndefun = "defun";
94 private static Name Nfname = "fname";
95 private static Name Nargs = "args";
96 private static Name Nargs_unevalled = "args-unevalled";
97 private static Name Noptional = "optional";
98 private static Name Nrest = "rest";
99 private static Name Nbody = "body";
101 private static Name Ndefvar = "defvar";
102 private static Name Ndescription = "description";
103 private static Name Nrange = "range";
105 private static Name Nprogn = "progn";
107 internal abstract class Function
110 public int min_arg, max_arg;
112 public Function () { }
114 public Function (Name name, int min_arg, int max_arg)
117 this.min_arg = min_arg;
118 this.max_arg = max_arg;
121 public abstract Term Call (Domain domain, Term[] args);
123 public override string ToString ()
128 internal class Subroutine : Function
130 public Builtin builtin;
132 public Subroutine (Builtin builtin, Name name,
133 int min_arg, int max_arg)
134 : base (name, min_arg, max_arg)
136 this.builtin = builtin;
139 public override Term Call (Domain domain, Term[] args)
141 Term[] newargs = new Term[args.Length];
143 for (int i = 0; i < args.Length; i++)
144 newargs[i] = args[i].Eval (domain);
145 return builtin (domain, newargs);
149 internal class SpecialForm : Function
151 public Builtin builtin;
153 public SpecialForm (Builtin builtin, Name name,
154 int min_arg, int max_arg)
155 : base (name, min_arg, max_arg)
157 this.builtin = builtin;
160 public override Term Call (Domain domain, Term[] args)
162 return builtin (domain, args);
166 internal class Lambda : Function
168 internal bool args_evalled;
169 internal Term[] args;
170 internal Term[] body;
172 public Lambda (XmlNode node)
174 int nargs = 0, noptions = 0, nrest = 0;
175 name = node.Attributes[Nfname].Value;
177 node = node.FirstChild;
179 && (node.Name == Nargs || node.Name == Nargs_unevalled))
182 args_evalled = node.Name == Nargs;
183 for (n = node.FirstChild; n != null; n = n.NextSibling)
185 if (n.Name != Nsymbol)
189 if (n != null && n.Name == Noptional)
190 for (n = n.NextSibling; n != null; n = n.NextSibling)
199 max_arg = nargs + noptions + nrest;
200 args = new Term[max_arg];
202 for (int i = 0; i < max_arg; n = n.NextSibling)
203 if (n.Name == Nsymbol)
204 args[i++] = new Term (n, null);
210 min_arg = max_arg = 0;
214 public void SetBody (XmlNode node, Domain domain)
217 for (node = node.FirstChild; node != null && node.Name != Nbody;
218 node = node.NextSibling);
221 XmlNodeList nlist = node.ChildNodes;
223 body = new Term[nlist.Count];
224 for (int i = 0; i < nlist.Count; i++)
225 body[i] = new Term (nlist[i], domain);
229 public override Term Call (Domain domain, Term[] args)
231 Bindings current = domain.bindings;
238 Term[] newargs = new Term[args.Length];
239 for (i = 0; i < min_arg; i++)
240 newargs[i] = args[i].Eval (domain);
243 for (i = 0; i < min_arg; i++)
245 Variable var = domain.GetVar ((Name) this.args[i]);
246 domain.Bind (var, args[i]);
249 foreach (Term term in body)
250 result = term.Eval (domain);
252 domain.UnboundTo (current);
259 internal abstract class Variable
261 public readonly Name name;
264 public Variable (Name name, Term term)
275 if (! ValueP (value))
276 throw new Exception ("Invalid value of " + name + ": " + value);
281 public abstract bool ValueP (Term term);
283 public override string ToString () { return name + "(" + val + ")"; }
285 internal class Int : Variable
292 public Range[] ranges;
294 public Int (Name name, int i) : base (name, new Term (i)) { }
296 public override bool ValueP (Term term)
300 if (term.objval != null)
305 foreach (Range r in ranges)
306 if (i >= r.from && i <= r.to)
312 internal class Str : Variable
314 public string[] ranges;
316 public Str (Name name, string str) : base (name, new Term (str)) { }
318 public override bool ValueP (Term term)
320 if (! (term.objval is string))
324 string str = (string) term.objval;
325 foreach (string s in ranges)
332 internal class Misc : Variable
334 public Misc (Name name, Term term) : base (name, term) { }
336 public override bool ValueP (Term term) { return true; }
340 internal class Bindings
342 private Variable vari;
343 private Term old_value;
344 private Bindings next;
346 private Bindings (Variable vari)
349 old_value = vari.val;
352 public static Bindings Bind (Bindings bindings, Variable vari, Term val)
354 Bindings b = new Bindings (vari);
361 internal Bindings UnboundTo (Bindings boundary)
363 for (Bindings b = this; b != boundary; b = b.next)
364 b.vari.val = b.old_value;
368 public override string ToString ()
370 string str = "(bindings";
371 for (Bindings b = this; b != null; b = b.next)
372 str += " " + vari.name + "=" + b.old_value;
378 internal class ThrowException : Exception
383 public ThrowException (Name tag, object value) : base ()
393 public object context;
394 public int depth = 0;
396 internal Dictionary<Name, Function> functions;
397 internal Dictionary<Name, Variable> variables;
398 internal Bindings bindings;
402 functions = new Dictionary<Name, Function> ();
403 variables = new Dictionary<Name, Variable> ();
406 public Domain (object context) : this (basic, context)
410 public Domain (Domain parent, object context)
412 functions = new Dictionary<Name, Function> (parent.functions);
413 variables = new Dictionary<Name, Variable> (parent.variables);
414 this.context = context;
417 internal void Bind (Variable vari, Term value)
419 bindings = Bindings.Bind (bindings, vari, value);
422 internal void UnboundTo (Bindings boundary)
424 if (bindings != null)
425 bindings = bindings.UnboundTo (boundary);
428 public void DefSubr (Builtin builtin, string str,
429 int min_arg, int max_arg)
433 = new Function.Subroutine (builtin, name, min_arg, max_arg);
436 public void DefSpecial (Builtin builtin, string str,
437 int min_arg, int max_arg)
441 = new Function.SpecialForm (builtin, name, min_arg, max_arg);
444 internal Function.Lambda RegisterFunction (XmlNode node)
446 Function.Lambda lambda = new Function.Lambda (node);
448 functions[lambda.name] = lambda;
452 internal Function Defun (XmlNode node)
454 Name name = node.Attributes[Nfname].Value;
457 if (! functions.TryGetValue (name, out func))
458 func = RegisterFunction (node);
459 ((Function.Lambda) func).SetBody (node, this);
463 public void Defvar (XmlNode node)
465 Name name = node.Attributes[0].Value;
468 node = node.FirstChild;
469 if (node.Name == Ndescription)
470 node = node.NextSibling;
473 Name type = node.Name;
474 XmlNodeList range_list = null;
476 string val = node.InnerText;
478 node = node.NextSibling;
481 range_list = node.ChildNodes;
482 nranges = range_list.Count;
485 if (type == Ninteger)
487 Variable.Int vi = new Variable.Int (name, parse_integer (val));
488 if (range_list != null)
490 vi.ranges = new Variable.Int.Range[nranges];
492 for (int i = 0; i < nranges; i++)
494 XmlNode n = range_list[i];
496 if (n.Name == Nrange)
499 parse_integer (n.FirstChild.InnerText);
501 parse_integer (n.LastChild.InnerText);
505 int num = parse_integer (n.InnerText);
506 vi.ranges[i].from = vi.ranges[i].to = num;
512 else if (type == Nstring)
514 Variable.Str vs = new Variable.Str (name, val);
515 if (range_list != null)
516 vs.ranges = new string[nranges];
517 for (int i = 0; i < nranges; i++)
518 vs.ranges[i] = range_list[i].Value;
522 throw new Exception ("Unknown type: " + type);
525 vari = new Variable.Misc (name, Zero);
526 variables[name] = vari;
529 internal Function GetFunc (Name name)
533 if (! functions.TryGetValue (name, out func))
534 throw new Exception ("Unknown function: " + name);
538 public bool CopyFunc (Domain domain, Name name)
540 Function func = GetFunc (name);
542 domain.functions[name] = func;
546 public void CopyFunc (Domain domain)
548 foreach (KeyValuePair<Name, Function> kv in functions)
549 domain.functions[kv.Key] = kv.Value;
552 internal Variable GetVar (Name name)
556 if (! variables.TryGetValue (name, out vari))
557 variables[name] = vari = new Variable.Misc (name, Zero);
561 public override string ToString ()
563 string str = "<(functions";
564 foreach (KeyValuePair<Name, Function> kv in functions)
566 str += ") (variabls";
567 foreach (KeyValuePair<Name, Variable> kv in variables)
570 if (bindings != null)
571 str += " " + bindings;
573 str += " (" + context + ")";
578 public void DebugWrite (bool head, string fmt, params string[] arg)
580 if (debug_level > depth)
584 Console.WriteLine ();
585 for (int i = 0; i < depth; i++)
588 Console.Write (fmt, arg);
593 public delegate Term Builtin (Domain domain, Term[] args);
595 private static Domain basic = new Domain ();
597 internal static Function Fprogn;
599 static Xexpression ()
601 basic.DefSubr (set_value, "set", 2, 2);
602 basic.DefSubr (set_value, "=", 2, 2);
603 basic.DefSpecial (and, "and", 1, -1);
604 basic.DefSpecial (and, "&&", 1, -1);
605 basic.DefSpecial (or, "or", 1, -1);
606 basic.DefSpecial (or, "||", 1, -1);
607 basic.DefSubr (not, "not", 1, 1);
608 basic.DefSubr (not, "!", 1, 1);
609 basic.DefSubr (add, "add", 2, -1);
610 basic.DefSubr (add, "+", 2, -1);
611 basic.DefSubr (mul, "mul", 2, -1);
612 basic.DefSubr (mul, "*", 2, -1);
613 basic.DefSubr (sub, "sub", 1, -1);
614 basic.DefSubr (sub, "-", 1, -1);
615 basic.DefSubr (div, "div", 2, -1);
616 basic.DefSubr (div, "/", 2, -1);
617 basic.DefSubr (mod, "mod", 2, 2);
618 basic.DefSubr (mod, "%", 2, 2);
619 basic.DefSubr (logior, "logior", 2, -1);
620 basic.DefSubr (logior, "|", 2, -1);
621 basic.DefSubr (logand, "logand", 2, -1);
622 basic.DefSubr (logand, "&", 2, -1);
623 basic.DefSubr (add_set, "add-set", 2, -1);
624 basic.DefSubr (add_set, "+=", 2, -1);
625 basic.DefSubr (mul_set, "mul-set", 2, -1);
626 basic.DefSubr (mul_set, "*=", 2, -1);
627 basic.DefSubr (sub_set, "sub-set", 2, -1);
628 basic.DefSubr (sub_set, "-=", 2, -1);
629 basic.DefSubr (div_set, "div-set", 2, -1);
630 basic.DefSubr (div_set, "/=", 2, -1);
631 basic.DefSubr (mod_set, "mod-set", 2, 2);
632 basic.DefSubr (mod_set, "%=", 2, 2);
633 basic.DefSubr (logior_set, "logior-set", 2, -1);
634 basic.DefSubr (logior_set, "|=", 2, -1);
635 basic.DefSubr (logand_set, "logand-set", 2, -1);
636 basic.DefSubr (logand_set, "&=", 2, -1);
637 basic.DefSubr (lsh, "lsh", 2, 2);
638 basic.DefSubr (lsh, "<<", 2, 2);
639 basic.DefSubr (rsh, "rsh", 2, 2);
640 basic.DefSubr (rsh, ">>", 2, 2);
641 basic.DefSubr (lsh_set, "lsh-set", 2, 2);
642 basic.DefSubr (lsh_set, "<<=", 2, 2);
643 basic.DefSubr (rsh_set, "rsh-set", 2, 2);
644 basic.DefSubr (rsh_set, ">>=", 2, 2);
645 basic.DefSubr (eq, "eq", 2, -1);
646 basic.DefSubr (eq, "==", 2, -1);
647 basic.DefSubr (noteq, "noteq", 2, 2);
648 basic.DefSubr (noteq, "!=", 2, 2);
649 basic.DefSubr (less_than, "lt", 2, -1);
650 basic.DefSubr (less_than, "<", 2, -1);
651 basic.DefSubr (less_eq, "le", 2, -1);
652 basic.DefSubr (less_eq, "<=", 2, -1);
653 basic.DefSubr (greater_than, "gt", 2, -1);
654 basic.DefSubr (greater_than, ">", 2, -1);
655 basic.DefSubr (greater_eq, "ge", 2, -1);
656 basic.DefSubr (greater_eq, ">=", 2, -1);
657 basic.DefSubr (copy, "copy", 1, 1);
658 basic.DefSubr (append, "append", 1, -1);
659 basic.DefSpecial (quote_clause, "quote", 1, 1);
660 basic.DefSubr (eval_clause, "eval", 1, 1);
661 basic.DefSpecial (progn_clause, "progn", 0, -1);
662 basic.DefSpecial (progn_clause, "expr", 0, -1);
663 basic.DefSpecial (if_clause, "if", 2, -1);
664 basic.DefSpecial (when_clause, "when", 1, -1);
665 basic.DefSpecial (while_clause, "while", 1, -1);
667 Fprogn = basic.GetFunc (Nprogn);
670 private static Term set_value (Domain domain, Term[] args)
672 Variable vari = domain.GetVar ((Name) args[0]);
674 vari.Value = args[1];
678 private static Term and (Domain domain, Term[] args)
680 foreach (Term arg in args)
681 if (! arg.Eval (domain).IsTrue)
686 private static Term or (Domain domain, Term[] args)
688 foreach (Term arg in args)
689 if (arg.Eval (domain).IsTrue)
694 private static Term not (Domain domain, Term[] args)
696 return args[0].IsTrue ? Zero : One;
699 private static Term add (Domain domain, Term[] args)
702 foreach (Term arg in args)
707 private static Term mul (Domain domain, Term[] args)
710 foreach (Term arg in args)
715 private static Term sub (Domain domain, Term[] args)
717 int n = (int) args[0];
718 if (args.Length == 1)
720 for (int i = 1; i < args.Length; i++)
725 private static Term div (Domain domain, Term[] args)
727 int n = (int) args[0];
728 for (int i = 1; i < args.Length; i++)
733 private static Term mod (Domain domain, Term[] args)
735 return ((int) args[0] % (int) args[1]);
738 private static Term logior (Domain domain, Term[] args)
741 foreach (Term arg in args)
746 private static Term logand (Domain domain, Term[] args)
748 int n = (int) args[0];
749 for (int i = 1; i < args.Length; i++)
754 private static Term add_set (Domain domain, Term[] args)
756 Variable vari = domain.GetVar ((Name) args[0]);
757 int n = (int) vari.val;
759 for (int i = 1; i < args.Length; i++)
765 private static Term mul_set (Domain domain, Term[] args)
767 Variable vari = domain.GetVar ((Name) args[0]);
768 int n = (int) vari.val;
770 for (int i = 1; i < args.Length; i++)
776 private static Term sub_set (Domain domain, Term[] args)
778 Variable vari = domain.GetVar ((Name) args[0]);
779 int n = (int) vari.val;
781 for (int i = 1; i < args.Length; i++)
787 private static Term div_set (Domain domain, Term[] args)
789 Variable vari = domain.GetVar ((Name) args[0]);
790 int n = (int) vari.val;
792 for (int i = 1; i < args.Length; i++)
798 private static Term mod_set (Domain domain, Term[] args)
800 Variable vari = domain.GetVar ((Name) args[0]);
801 int n = (int) vari.val;
803 for (int i = 1; i < args.Length; i++)
809 private static Term logior_set (Domain domain, Term[] args)
811 Variable vari = domain.GetVar ((Name) args[0]);
812 int n = (int) vari.val;
814 for (int i = 1; i < args.Length; i++)
820 private static Term logand_set (Domain domain, Term[] args)
822 Variable vari = domain.GetVar ((Name) args[0]);
823 int n = (int) vari.val;
825 for (int i = 1; i < args.Length; i++)
831 private static Term lsh (Domain domain, Term[] args)
833 return (int) args[0] << (int) args[1];
836 private static Term lsh_set (Domain domain, Term[] args)
838 Variable vari = domain.GetVar ((Name) args[0]);
839 int n = (int) vari.val;
846 private static Term rsh (Domain domain, Term[] args)
848 return (int) args[0] >> (int) args[1];
851 private static Term rsh_set (Domain domain, Term[] args)
853 Variable vari = domain.GetVar ((Name) args[0]);
854 int n = (int) vari.val;
861 private static Term eq (Domain domain, Term[] args)
865 if (o.objval == null)
867 for (int i = 1; i < args.Length; i++)
868 if (args[i].objval != null || args[i].intval != o.intval)
873 for (int i = 1; i < args.Length; i++)
874 if (o.objval.Equals (args[i].objval))
880 private static Term noteq (Domain domain, Term[] args)
882 return eq (domain, args);
885 private static Term less_than (Domain domain, Term[] args)
887 int n = (int) args[0];
889 for (int i = 1; i < args.Length; i++)
891 int n1 = (int) args[i];
899 private static Term less_eq (Domain domain, Term[] args)
901 int n = (int) args[0];
902 for (int i = 1; i < args.Length; i++)
904 int n1 = (int) args[i];
912 private static Term greater_than (Domain domain, Term[] args)
914 int n = (int) args[0];
915 for (int i = 1; i < args.Length; i++)
917 int n1 = (int) args[i];
925 private static Term greater_eq (Domain domain, Term[] args)
927 int n = (int) args[0];
928 for (int i = 1; i < args.Length; i++)
930 int n1 = (int) args[i];
938 private static Term copy (Domain domain, Term[] args)
940 object obj = args[0].objval;
942 if (! (obj is List<Term>))
943 throw new Exception ("Invalid arg to copy: " + args[0]);
944 return new Term (new List<Term> ((List<Term>) obj));
947 private static Term append (Domain domain, Term[] args)
949 object obj = args[0].objval;
953 foreach (Term arg in args)
955 return new Term (str);
957 else if (obj is List<Term>)
959 List<Term> list = new List<Term> ();
960 foreach (Term arg in args)
961 list.AddRange ((List<Term>) arg.objval);
962 return new Term (list);
964 throw new Exception ("Invalid term to append: " + obj);
967 private static Term quote_clause (Domain domain, Term[] args)
969 return new Term (args[0]);
972 private static Term eval_clause (Domain domain, Term[] args)
974 return (args[0].Eval (domain));
977 private static Term progn_clause (Domain domain, Term[] args)
981 foreach (Term arg in args)
982 result = arg.Eval (domain);
986 private static Term if_clause (Domain domain, Term[] args)
988 if (args[0].Eval (domain).IsTrue)
989 return args[1].Eval (domain);
992 for (int i = 2; i < args.Length; i++)
993 result = args[i].Eval (domain);
997 private static Term when_clause (Domain domain, Term[] args)
999 if (! args[0].Eval (domain).IsTrue)
1003 for (int i = 1; i < args.Length; i++)
1004 result = args[i].Eval (domain);
1008 private static Term while_clause (Domain domain, Term[] args)
1010 while (args[0].Eval (domain).IsTrue)
1011 for (int i = 1; i < args.Length; i++)
1012 args[i].Eval (domain);
1019 public object objval;
1021 public Term (int i) { intval = i; objval = null; }
1022 public Term (Name name) { intval = 0; objval = name; }
1023 public Term (string str) { intval = 0; objval = str; }
1024 public Term (List<Term> list) { intval = 0; objval = list; }
1025 public Term (Term term) { intval = 0; objval = term; }
1027 public Term (XmlNode node, Domain domain)
1029 Name name = node.Name;
1031 if (name == Ninteger)
1033 intval = parse_integer (node.InnerText);
1039 if (name == Nsymbol)
1040 objval = (Name) node.InnerText;
1041 else if (name == Nstring)
1042 objval = node.InnerText.Clone ();
1043 else if (name == Nvariable)
1044 objval = domain.GetVar ((Name) node.Attributes[0].Value);
1045 else if (name == Nlist)
1047 List<Term> list = new List<Term> ();
1048 for (node = node.FirstChild; node != null;
1049 node = node.NextSibling)
1050 list.Add (new Term (node, domain));
1055 if (name == Nfuncall)
1056 name = node.Attributes[0].Value;
1058 Function func = domain.GetFunc (name);
1059 XmlNodeList nlist = node.ChildNodes;
1060 int nargs = nlist.Count;
1062 if (nargs < func.min_arg
1063 || (func.max_arg >= 0 && nargs > func.max_arg))
1064 throw new Exception ("Invalid number of arguments to: "
1065 + name + " " + nargs);
1066 Term[] args = new Term[nargs];
1067 for (int i = 0; i < nlist.Count; i++)
1068 args[i] = new Term (nlist[i], domain);
1069 objval = new Funcall (func, args);
1074 private class Funcall
1076 internal Function func;
1077 internal Term[] args;
1079 public Funcall (Function func, Term[] args)
1085 public Term Eval (Domain domain)
1087 domain.DebugWrite (true, "(({0}", func.name);
1088 for (int i = 0; i < args.Length; i++)
1089 domain.DebugWrite (false, " {0}", args[i].ToString ());
1090 domain.DebugWrite (false, ")");
1092 Term result = func.Call (domain, args);
1094 domain.DebugWrite (true, " ==> {0})", result.ToString ());
1098 public override string ToString ()
1100 string str = "<funcall fname=\"" + func.name;
1102 return str + "\"/>";
1104 foreach (Term e in args)
1106 return (str + "</funcall>");
1110 public bool IsTrue {
1112 return (objval == null
1114 : objval is List<Term>
1115 ? (((List<Term>) objval).Count != 0)
1120 public Term Eval (Domain domain)
1122 if (objval == null || objval is Name || objval is string)
1124 if (objval is List<Term>)
1125 return new Term ((List<Term>) objval);
1126 if (objval is Funcall)
1127 return ((Funcall) objval).Eval (domain);
1128 if (objval is Variable)
1129 return ((Variable) objval).val;
1131 return (Term) objval;
1132 throw new Exception ("invalid Term object: " + objval);
1135 public static explicit operator int (Term term)
1137 if (term.objval != null)
1138 throw new Exception ("Not an integer term: " + term);
1142 public static explicit operator Name (Term term)
1144 return (Name) term.objval;
1147 public static implicit operator Term (int i)
1149 return new Term (i);
1152 public override string ToString ()
1157 str = "<integer>" + intval + "</integer>";
1158 else if (objval is Name)
1159 str = "<symbol>" + objval + "</symbol>";
1160 else if (objval is string)
1161 str = "<string>" + objval + "</string>";
1162 else if (objval is List<Term>)
1165 foreach (Term e in (List<Term>) objval)
1169 else if (objval is Funcall)
1170 str = "<funcall fname=\"" + ((Funcall) objval).func.name + "\"/>";
1171 else if (objval is Variable)
1172 str = "<variable vname=\"" + ((Variable) objval).name + "\"/>";
1173 else if (objval is Term)
1174 str = "<quote>" + objval + "</quote>";
1176 throw new Exception ("invalid Term object: " + objval);
1181 static Term Zero = new Term (0);
1182 static Term One = new Term (1);
1184 internal static int parse_integer (string str)
1186 int len = str.Length;
1187 bool negative = false;
1190 return (len == 0 ? 0 : str[0] - '0');
1195 if (c == '0' && str[1] == 'x')
1198 for (int idx = 2; idx < len; idx++)
1204 i = i * 16 + (c - '0');
1208 i = i * 16 + (c - 'A');
1212 i = i * 16 + (c - 'a');
1221 for (int idx = 1; idx < len; idx++)
1224 if (c < '0' || c > '9')
1226 i = i * 10 + (c - '0');
1228 return negative ? - i : i;
1231 private Term[] terms;
1233 public Xexpression (string url, Domain domain)
1235 XmlDocument doc = new XmlDocument (Name.Table);
1238 using (XmlTextReader reader = new XmlTextReader (url, Name.Table))
1242 } while (reader.NodeType != XmlNodeType.None
1243 && (reader.NodeType != XmlNodeType.Element
1244 || reader.Name != Nexpr));
1245 if (reader.NodeType == XmlNodeType.None)
1246 throw new Exception ("Node <expr> not found");
1247 node = doc.ReadNode (reader);
1251 for (XmlNode n = node.FirstChild; n != null; n = n.NextSibling)
1252 if (n.NodeType == XmlNodeType.Element)
1254 if (n.Name == Ndefun)
1255 domain.RegisterFunction (n);
1256 else if (n.Name == Ndefvar)
1262 terms = new Term[nterms];
1264 for (XmlNode n = node.FirstChild; n != null; n = n.NextSibling)
1265 if (n.NodeType == XmlNodeType.Element)
1267 if (n.Name == Ndefun)
1269 else if (n.Name != Ndefvar)
1271 terms[i]= new Term (n, domain);
1272 Console.WriteLine ("term="+terms[i]);
1277 public Term Eval (Domain domain)
1282 for (int i = 0; i < terms.Length; i++)
1283 Console.WriteLine (terms[i]);
1285 foreach (Term term in terms)
1287 Console.WriteLine (term);
1288 result = term.Eval (domain);
1289 Console.WriteLine ("=>" + result);