2 using System.Collections;
3 using System.Collections.Generic;
5 using System.Reflection;
10 public class Xexpression
12 private static int debug_depth = 0;
14 public static int DebugDepth {
15 get { return debug_depth; }
16 set { debug_depth = value; }
19 public struct Symbol : IEquatable<Symbol>
21 private static NameTable nt = new NameTable ();
25 public Symbol (string str) { name = nt.Add (str); }
27 public static implicit operator Symbol (string str)
29 return new Symbol (str);
32 public static implicit operator string (Symbol sym) { return sym.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 NameTable { 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 public static Symbol Qdefun = "defun";
94 public 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 public 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;
382 public Variable (Domain domain, Symbol name, Term val)
384 this.domain = domain;
389 public virtual bool ValueP (Term val) { return true; }
391 public virtual Variable Clone (Domain domain)
393 return new Variable (domain, name, val);
396 public virtual void Reset () { val = Zero; }
402 if (! ValueP (value))
403 throw new Exception ("Invalid value: " + value);
408 public Term SetValue (int i)
415 public Term SetValue (string s)
421 public override string ToString () { return name + "(" + val + ")"; }
423 public abstract class Typed : Variable
425 protected string desc;
426 private Term default_val;
428 protected Typed (Domain domain, Symbol name, Term val, string desc)
429 : base (domain, name, val)
435 public override void Reset () { val = default_val; }
437 public string Description {
439 set { desc = value; }
443 public class Int : Typed
447 public bool IsSubrange (int[] r)
451 for (int i = 0; i < r.Length; i += 2)
454 for (j = 0; j < range.Length; j += 2)
455 if (range[j] <= r[i] && range[j + 1] >= r[i + 1])
457 if (j >= range.Length)
463 public Int (Domain domain, Symbol name, int n, string desc, int[] range)
464 : base (domain, name, new Term (n), desc)
466 if (range != null && range.Length % 2 == 1)
467 throw_exception ("Range length for {0} not even", name);
470 throw_exception ("Invalid integer value for {0}: {1}", name, val);
473 public override bool ValueP (Term term)
480 for (int i = 0; i < range.Length; i += 2)
481 if (range[i] <= n && range[i + 1] >= n)
486 public override Variable Clone (Domain domain)
488 return new Int (domain, name, val.Intval, desc, range);
491 public int[] Range { get { return range; } set { range = value; } }
494 public class Str : Typed
496 private string[] range;
498 public bool IsSubrange (string[] r)
502 for (int i = 0; i < r.Length; i++)
505 for (j = 0; j < range.Length; j++)
506 if (range[j] == r[i])
508 if (j >= range.Length)
514 public Str (Domain domain, Symbol name, string str, string desc,
516 : base (domain, name, new Term (str), desc)
520 throw_exception ("Invalid string value for {0}: {1}", name, val);
523 public override bool ValueP (Term term)
529 string str = term.Strval;
530 foreach (string s in range)
536 public override Variable Clone (Domain domain)
538 return new Str (domain, name, val.Strval, desc, range);
541 public string[] Range { get { return range; } set { range = value; } }
544 public class Sym : Typed
546 public Symbol[] range;
548 public bool IsSubrange (Symbol[] r)
552 for (int i = 0; i < r.Length; i++)
555 for (j = 0; j < range.Length; j++)
556 if (range[j] == r[i])
558 if (j >= range.Length)
564 public Sym (Domain domain, Symbol name, Symbol sym, string desc,
566 : base (domain, name, new Term (sym), desc)
570 throw_exception ("Invalid symbol value for {0}: {1}", name, val);
573 public override bool ValueP (Term term)
579 Symbol name = term.Symval;
580 foreach (Symbol n in range)
586 public override Variable Clone (Domain domain)
588 return new Sym (domain, name, val.Symval, desc, range);
591 public Symbol[] Range { get { return range; } set { range = value; } }
595 internal class Bindings
597 private Variable vari;
598 private Term old_value;
599 private Bindings next;
601 private Bindings (Variable vari)
604 old_value = vari.Value;
607 public static Bindings Bind (Bindings bindings, Variable vari, Term val)
609 Bindings b = new Bindings (vari);
616 internal Bindings UnboundTo (Bindings boundary)
618 for (Bindings b = this; b != boundary; b = b.next)
619 b.vari.Value = b.old_value;
623 public override string ToString ()
625 string str = "(bindings";
626 for (Bindings b = this; b != null; b = b.next)
627 str += " " + vari.name + "=" + b.old_value;
632 private static void throw_exception (string msg)
634 throw new Exception (msg);
637 private static void throw_exception (string fmt, params object[] args)
639 throw new Exception (String.Format (fmt, args));
642 internal class CatchTag : IEquatable<CatchTag>
646 public CatchTag (Symbol sym) { val = (string) sym; }
647 private CatchTag (int i) { val = i; }
649 public static CatchTag Return = new CatchTag (0);
650 public static CatchTag Break = new CatchTag (1);
652 public static bool operator== (CatchTag t1, CatchTag t2)
653 { return t1.val == t2.val; }
655 public static bool operator!= (CatchTag t1, CatchTag t2)
656 { return t1.val != t2.val; }
658 public bool Equals (CatchTag tag) { return this.val == tag.val; }
659 public override bool Equals (object val) { return this.val == val; }
661 public override int GetHashCode () { return val.GetHashCode (); }
667 public object context;
668 public int depth = 0;
670 internal Dictionary<Symbol, TermType> termtypes
671 = new Dictionary<Symbol, TermType> ();
672 internal Dictionary<Symbol, Function> functions
673 = new Dictionary<Symbol, Function> ();
674 internal Dictionary<Symbol, Variable> variables
675 = new Dictionary<Symbol, Variable> ();
676 internal Bindings bindings;
677 private Stack<CatchTag> catch_stack = new Stack<CatchTag> ();
678 private int catch_count = 0;
680 internal Domain (Symbol name) { this.name = name; }
682 public Domain (Symbol name, object context)
683 : this (name, basic, context) { }
685 public Domain (Symbol name, Domain parent, object context) : this (name)
687 termtypes = new Dictionary<Symbol, TermType> (parent.termtypes);
688 functions = new Dictionary<Symbol, Function> (parent.functions);
689 variables = new Dictionary<Symbol, Variable> (parent.variables);
690 this.context = context;
693 internal void Bind (Variable vari, Term value)
695 bindings = Bindings.Bind (bindings, vari, value);
698 internal void UnboundTo (Bindings boundary)
700 if (bindings != null)
701 bindings = bindings.UnboundTo (boundary);
704 internal void Catch (CatchTag tag)
706 catch_stack.Push (tag);
710 internal void Uncatch ()
713 if (catch_count > catch_stack.Count)
718 get { return catch_count < catch_stack.Count; }
721 internal void ThrowReturn ()
723 foreach (CatchTag tag in catch_stack)
726 if (tag == CatchTag.Return)
731 internal void ThrowBreak ()
733 if (catch_stack.Peek () != CatchTag.Break)
734 throw_exception ("No outer loop to break");
738 internal void ThrowTag (CatchTag tag)
740 foreach (CatchTag elt in catch_stack)
748 public void DefTerm (Symbol name, TermParser parser)
750 if (termtypes.ContainsKey (name)
751 || functions.ContainsKey (name))
752 throw new Exception ("already defined: " + name);
753 termtypes[name] = new TermType (name, parser);
756 public void DefType (Type type)
758 if (! type.IsSubclassOf (typeof (TermValue)))
759 throw new Exception ("Not a subclass of TermValue: " + type);
760 BindingFlags flags = BindingFlags.Static | BindingFlags.NonPublic;
761 FieldInfo finfo = type.GetField ("name", flags);
763 throw new Exception ("No \"name\" field: " + type);
764 Type[] types = new Type[] { typeof (Domain), typeof (XmlNode),
765 typeof (TermValue) };
766 MethodInfo minfo = type.GetMethod ("Parser");
768 throw new Exception ("No \"Parser\" method: " + type);
771 public void DefSubr (Builtin builtin, string str, bool setvar,
772 int min_arg, int max_arg, params string[] aliases)
775 if (termtypes.ContainsKey (name))
776 throw new Exception ("already defined as termtype: " + name);
777 Function func = new Function.Subroutine (builtin, name, setvar,
779 functions[name] = func;
780 foreach (string a in aliases)
781 functions[(Symbol) a] = func;
784 public void DefSpecial (Builtin builtin, string str,
785 int min_arg, int max_arg,
786 params string[] aliases)
789 if (termtypes.ContainsKey (name))
790 throw new Exception ("already defined as termtype: " + name);
791 Function func = new Function.SpecialForm (builtin, name,
793 functions[name] = func;
794 foreach (string a in aliases)
795 functions[(Symbol) a] = func;
798 public void DefAlias (string alias, string str)
800 functions[(Symbol) alias] = functions[(Symbol) str];
803 public void Defun (Symbol name, Symbol[] args, Term[] body,
808 if (termtypes.ContainsKey (name))
809 throw new Exception ("already defined as termtype: " + name);
810 if (prototype || ! functions.TryGetValue (name, out func))
812 func = new Function.Lambda (this, name, args);
813 functions[name] = func;
816 ((Function.Lambda) func).SetBody (body);
819 public void Defun (XmlNode node, bool prototype)
821 Symbol name = node.Attributes[Qfname].Value;
822 if (termtypes.ContainsKey (name))
823 throw new Exception ("already defined as termtype: " + name);
826 if (prototype || ! functions.TryGetValue (name, out func))
828 func = new Function.Lambda (this, node);
829 functions[name] = func;
832 ((Function.Lambda) func).SetBody (this, node);
835 public void Defun (Function func)
837 functions[func.name] = func;
840 public void Defmacro (XmlNode node, bool prototype)
842 Symbol name = node.Attributes[Qfname].Value;
843 if (termtypes.ContainsKey (name))
844 throw new Exception ("already defined as termtype: " + name);
847 if (prototype || ! functions.TryGetValue (name, out func))
849 func = new Function.Macro (this, node);
850 functions[name] = func;
853 ((Function.Macro) func).SetBody (this, node);
856 public Variable Defvar (XmlNode node)
858 Symbol name = node.Attributes[0].Value;
862 node = node.FirstChild;
863 if (node != null && node.Name == Qdescription)
865 desc = node.InnerText;
866 node = node.NextSibling;
872 Symbol type = node.Name;
873 XmlNodeList range_list = null;
875 string val = node.InnerText;
877 node = node.NextSibling;
880 range_list = node.ChildNodes;
881 nranges = range_list.Count;
884 if (type == Qinteger)
886 int n = parse_integer (val);
888 if (range_list != null)
890 range = new int[nranges * 2];
891 for (int i = 0; i < nranges; i++)
893 XmlNode nd = range_list[i];
894 if (nd.Name == Qrange)
897 = parse_integer (nd.FirstChild.InnerText);
899 = parse_integer (nd.LastChild.InnerText);
905 = parse_integer (nd.FirstChild.InnerText);
909 vari = DefvarInt (name, n, desc, range);
911 else if (type == Qstring)
913 string[] range = null;
914 if (range_list != null)
916 range = new string[nranges];
917 for (int i = 0; i < nranges; i++)
918 range[i] = range_list[i].FirstChild.InnerText;
920 vari = DefvarStr (name, val, desc, range);
922 else if (type == Qsymbol)
924 Symbol[] range = null;
925 if (range_list != null)
927 range = new Symbol[nranges];
928 for (int i = 0; i < nranges; i++)
929 range[i] = range_list[i].FirstChild.InnerText;
931 vari = DefvarSym (name, (Symbol) val, desc, range);
934 throw new Exception ("Unknown type: " + type);
938 if (variables.TryGetValue (name, out vari))
939 vari = vari.Clone (this);
941 vari = new Variable (this, name, Zero);
942 variables[name] = vari;
947 public Variable Defvar (Variable vari)
949 vari = vari.Clone (this);
950 variables[vari.name] = vari;
954 internal Variable Defvar (Symbol name)
956 Variable vari = new Variable (this, name, Zero);
957 variables[name] = vari;
961 public Variable DefvarInt (Symbol name, int n, string desc, int[] range)
965 if (variables.TryGetValue (name, out vari))
967 Variable.Int intvari = vari as Variable.Int;
969 throw new Exception ("Variable type mismatch: " + name);
972 if (! intvari.IsSubrange (range))
973 throw new Exception ("Variable range mismatch: " + name);
974 intvari.Range = range;;
977 intvari.Description = desc;
981 vari = new Variable.Int (this, name, n, desc, range);
982 variables[name] = vari;
987 public Variable DefvarStr (Symbol name, string str, string desc,
992 if (variables.TryGetValue (name, out vari))
994 Variable.Str strvari = vari as Variable.Str;
996 throw new Exception ("Variable type mismatch: " + name);
999 if (! strvari.IsSubrange (range))
1000 throw new Exception ("Variable range mismatch: " + name);
1001 strvari.Range = range;
1004 strvari.Description = desc;
1008 vari = new Variable.Str (this, name, str, desc, range);
1009 variables[name] = vari;
1014 public Variable DefvarSym (Symbol name, Symbol sym, string desc,
1019 if (variables.TryGetValue (name, out vari))
1021 Variable.Sym symvari = vari as Variable.Sym;
1022 if (symvari == null)
1023 throw new Exception ("Variable type mismatch: " + name);
1026 if (! symvari.IsSubrange (range))
1027 throw new Exception ("Variable range mismatch: " + name);
1028 symvari.Range = range;
1031 symvari.Description = desc;
1035 vari = new Variable.Sym (this, name, sym, desc, range);
1036 variables[name] = vari;
1041 internal Function GetFunc (Symbol name)
1045 if (! functions.TryGetValue (name, out func))
1046 throw new Exception ("Unknown function: " + name);
1050 public bool CopyFunc (Domain domain, Symbol name)
1052 Function func = GetFunc (name);
1054 domain.functions[name] = func;
1058 public void CopyFunc (Domain domain)
1060 foreach (KeyValuePair<Symbol, Function> kv in functions)
1061 domain.functions[kv.Key] = kv.Value;
1064 public Variable GetVar (Symbol name, bool create)
1068 if (! variables.TryGetValue (name, out vari))
1072 variables[name] = vari = new Variable (this, name, Zero);
1077 public override string ToString ()
1079 string str = "<(functions";
1080 foreach (KeyValuePair<Symbol, Function> kv in functions)
1081 str += " " + kv.Key;
1082 str += ") (variabls";
1083 foreach (KeyValuePair<Symbol, Variable> kv in variables)
1084 str += " " + kv.Value;
1086 if (bindings != null)
1087 str += " " + bindings;
1088 if (context != null)
1089 str += " (" + context + ")";
1094 internal void DebugWrite (string fmt, params string[] arg)
1096 if (debug_depth > depth)
1098 for (int i = 0; i < depth; i++)
1099 Console.Write (" ");
1100 Console.WriteLine (fmt, arg);
1104 public object SaveValues ()
1106 Dictionary<Variable,Term> values = new Dictionary<Variable,Term> ();
1108 foreach (KeyValuePair<Symbol,Variable> kv in variables)
1109 values[kv.Value] = kv.Value.Value.Clone ();
1113 public void RestoreValues (object values)
1115 foreach (KeyValuePair<Variable,Term> kv
1116 in (Dictionary<Variable,Term>) values)
1117 kv.Key.Value = kv.Value;
1121 public delegate Term Builtin (Domain domain, Variable vari, Term[] args);
1123 private static Domain basic = new Domain ("basic");
1125 static Xexpression ()
1127 basic.DefTerm ("funcall", Funcall.parser);
1128 basic.DefTerm ("varref", Varref.parser);
1129 basic.DefType (typeof (Funcall));
1131 basic.DefSubr (Fset, "set", true, 1, 1, "=");
1132 basic.DefSubr (Fnot, "not", false, 1, 1, "!");
1133 basic.DefSubr (Fadd, "add", true, 1, -1, "+");
1134 basic.DefSubr (Fmul, "mul", true, 1, -1, "*");
1135 basic.DefSubr (Fsub, "sub", true, 1, -1, "-");
1136 basic.DefSubr (Fdiv, "div", true, 1, -1, "/");
1137 basic.DefSubr (Fmod, "mod", true, 1, 2, "%");
1138 basic.DefSubr (Flogior, "logior", true, 1, -1, "|");
1139 basic.DefSubr (Flogand, "logand", true, 1, -1, "&");
1140 basic.DefSubr (Flsh, "lsh", true, 1, 2, "<<");
1141 basic.DefSubr (Frsh, "rsh", true, 1, 2, ">>");
1142 basic.DefSubr (Feq, "eq", false, 2, -1, "==");
1143 basic.DefSubr (Fnoteq, "noteq", false, 2, 2, "!=");
1144 basic.DefSubr (Flt, "lt", false, 2, -1, "<");
1145 basic.DefSubr (Fle, "le", false, 2, -1, "<=");
1146 basic.DefSubr (Fgt, "gt", false, 2, -1, ">");
1147 basic.DefSubr (Fge, "ge", false, 2, -1, ">=");
1148 basic.DefSubr (Fappend, "append", true, 0, -1);
1149 basic.DefSubr (Fconcat, "concat", true, 0, -1);
1150 basic.DefSubr (Fnth, "nth", false, 2, 2);
1151 basic.DefSubr (Fcopy, "copy", false, 1, 1);
1152 basic.DefSubr (Fins, "ins", true, 2, 2);
1153 basic.DefSubr (Fdel, "del", true, 2, 2);
1154 basic.DefSubr (Feval, "eval", false, 1, 1);
1155 basic.DefSubr (Fbreak, "break", false, 0, 1);
1156 basic.DefSubr (Freturn, "return", false, 0, 1);
1158 basic.DefSpecial (Fand, "and", 1, -1, "&&");
1159 basic.DefSpecial (For, "or", 1, -1, "||");
1160 basic.DefSpecial (Fprogn, "progn", 0, -1, "expr");
1161 basic.DefSpecial (Fif, "if", 2, 3);
1162 basic.DefSpecial (Fwhen, "when", 1, -1);
1163 basic.DefSpecial (Floop, "loop", 1, -1);
1164 basic.DefSpecial (Fwhile, "while", 1, -1);
1165 basic.DefSpecial (Fcond, "cond", 1, -1);
1166 basic.DefSpecial (Fforeach, "foreach", 2, -1);
1167 basic.DefSpecial (Fquote, "quote", 1, 1);
1168 basic.DefSpecial (Ftype, "type", 1, 1);
1169 basic.DefSpecial (Fcatch, "catch", 2, 2);
1170 basic.DefSpecial (Fthrow, "throw", 1, 2);
1173 private static Term Fset (Domain domain, Variable vari, Term[] args)
1175 vari.Value = args[0];
1179 private static Term Fnot (Domain domain, Variable vari, Term[] args)
1181 return args[0].IsTrue ? Zero : One;
1184 private static Term Fadd (Domain domain, Variable vari, Term[] args)
1186 int n = vari == null ? 0 : vari.Value.Intval;
1188 foreach (Term arg in args)
1190 return (vari == null ? new Term (n) : vari.SetValue (n));
1193 private static Term Fmul (Domain domain, Variable vari, Term[] args)
1195 int n = vari == null ? 1 : vari.Value.Intval;
1196 foreach (Term arg in args)
1198 return (vari == null ? new Term (n) : vari.SetValue (n));
1201 private static Term Fsub (Domain domain, Variable vari, Term[] args)
1212 n = vari.Value.Intval;
1215 while (i < args.Length)
1216 n -= args[i++].Intval;
1217 return (vari == null ? new Term (n) : vari.SetValue (n));
1220 private static Term Fdiv (Domain domain, Variable vari, Term[] args)
1231 n = vari.Value.Intval;
1234 while (i < args.Length)
1235 n /= args[i++].Intval;
1236 return (vari == null ? new Term (n) : vari.SetValue (n));
1239 private static Term Fmod (Domain domain, Variable vari, Term[] args)
1241 int n = args[0].Intval % args[1].Intval;
1243 return (vari == null ? new Term (n) : vari.SetValue (n));
1246 private static Term Flogior (Domain domain, Variable vari, Term[] args)
1248 int n = vari == null ? 0 : vari.Value.Intval;
1249 foreach (Term arg in args)
1251 return (vari == null ? new Term (n) : vari.SetValue (n));
1254 private static Term Flogand (Domain domain, Variable vari, Term[] args)
1265 n = vari.Value.Intval;
1268 while (i < args.Length)
1269 n &= args[i++].Intval;
1270 return (vari == null ? new Term (n) : vari.SetValue (n));
1273 private static Term Flsh (Domain domain, Variable vari, Term[] args)
1275 int n = args[0].Intval << args[1].Intval;
1276 return (vari == null ? new Term (n) : vari.SetValue (n));
1279 private static Term Frsh (Domain domain, Variable vari, Term[] args)
1281 int n = args[0].Intval >> args[1].Intval;
1282 return (vari == null ? new Term (n) : vari.SetValue (n));
1285 private static Term Feq (Domain domain, Variable vari, Term[] args)
1289 if (o.objval == null)
1291 for (int i = 1; i < args.Length; i++)
1292 if (args[i].objval != null || args[i].intval != o.intval)
1297 for (int i = 1; i < args.Length; i++)
1298 if (o.objval.Equals (args[i].objval))
1304 private static Term Fnoteq (Domain domain, Variable vari, Term[] args)
1306 return Feq (domain, vari, args);
1309 private static Term Flt (Domain domain, Variable vari, Term[] args)
1311 int n = args[0].Intval;
1313 for (int i = 1; i < args.Length; i++)
1315 int n1 = args[i].Intval;
1323 private static Term Fle (Domain domain, Variable vari, Term[] args)
1325 int n = args[0].Intval;
1326 for (int i = 1; i < args.Length; i++)
1328 int n1 = args[i].Intval;
1336 private static Term Fgt (Domain domain, Variable vari, Term[] args)
1338 int n = args[0].Intval;
1339 for (int i = 1; i < args.Length; i++)
1341 int n1 = args[i].Intval;
1349 private static Term Fge (Domain domain, Variable vari, Term[] args)
1351 int n = args[0].Intval;
1352 for (int i = 1; i < args.Length; i++)
1354 int n1 = args[i].Intval;
1362 private static Term Fappend (Domain domain, Variable vari, Term[] args)
1367 list = new List<Term> ();
1369 list = vari.Value.Listval;
1371 foreach (Term arg in args)
1374 list.AddRange ((List<Term>) arg.objval);
1382 result.objval = list;
1388 private static Term Fconcat (Domain domain, Variable vari, Term[] args)
1395 str = vari.Value.Strval;
1397 foreach (Term arg in args)
1400 str += (string) arg.objval;
1401 else if (arg.IsList)
1402 foreach (Term term in (List<Term>) arg.objval)
1403 str += (char) term.Intval;
1405 str += (char) arg.Intval;
1415 return vari.SetValue (str);
1418 private static Term Fnth (Domain domain, Variable vari, Term[] args)
1424 result.intval = ((string) args[1].objval)[args[0].Intval];
1425 result.objval = null;
1427 else if (args[1].IsList)
1429 result = ((List<Term>) args[1].objval)[args[0].Intval];
1432 throw new Exception ("Term is not enumelable: " + args[1]);
1436 private static Term Fcopy (Domain domain, Variable vari, Term[] args)
1441 result.objval = new List<Term> (args[0].Listval);
1445 private static Term Fins (Domain domain, Variable vari, Term[] args)
1447 Term term = vari.Value;
1451 string str = term.Strval.Insert (args[0].Intval, args[1].Strval);
1452 vari.SetValue (str);
1454 else if (vari.Value.IsList)
1455 vari.Value.Listval.InsertRange (args[0].Intval, args[1].Listval);
1457 throw new Exception ("term is not collection: " + vari.Value);
1461 private static Term Fdel (Domain domain, Variable vari, Term[] args)
1463 if (vari.Value.IsStr)
1466 = vari.Value.Strval.Remove (args[0].Intval,
1467 args[1].Intval - args[0].Intval);
1468 vari.SetValue (str);
1470 else if (vari.Value.IsList)
1471 vari.Value.Listval.RemoveRange (args[0].Intval,
1472 args[1].Intval - args[0].Intval);
1474 throw new Exception ("term is not collection: " + vari.Value);
1478 private static Term Fand (Domain domain, Variable vari, Term[] args)
1480 foreach (Term arg in args)
1481 if (! arg.Eval (domain).IsTrue)
1486 private static Term For (Domain domain, Variable vari, Term[] args)
1488 foreach (Term arg in args)
1489 if (arg.Eval (domain).IsTrue)
1494 private static Term Feval (Domain domain, Variable vari, Term[] args)
1496 return (args[0].Eval (domain));
1499 private static Term Fprogn (Domain domain, Variable vari, Term[] args)
1503 foreach (Term arg in args)
1504 result = arg.Eval (domain);
1508 private static Term Fif (Domain domain, Variable vari, Term[] args)
1510 if (args[0].Eval (domain).IsTrue)
1511 return args[1].Eval (domain);
1512 if (args.Length == 2)
1514 return args[2].Eval (domain);
1517 private static Term Fwhen (Domain domain, Variable vari, Term[] args)
1519 if (! args[0].Eval (domain).IsTrue)
1522 for (int i = 1; i < args.Length; i++)
1523 result = args[i].Eval (domain);
1527 private static Term Freturn (Domain domain, Variable vari, Term[] args)
1529 domain.ThrowReturn ();
1530 return args.Length == 0 ? Zero : args[0];
1533 private static Term Fbreak (Domain domain, Variable vari, Term[] args)
1535 domain.ThrowBreak ();
1536 return args.Length == 0 ? Zero : args[0];
1539 private static Term Floop (Domain domain, Variable vari, Term[] args)
1543 domain.Catch (CatchTag.Break);
1544 while (! domain.Thrown)
1545 foreach (Term arg in args)
1547 result = arg.Eval (domain);
1557 private static Term Fwhile (Domain domain, Variable vari, Term[] args)
1561 domain.Catch (CatchTag.Break);
1562 while (! domain.Thrown && args[0].Eval (domain).IsTrue)
1563 for (int i = 1; i < args.Length; i++)
1565 result = args[i].Eval (domain);
1575 private static Term Fcond (Domain domain, Variable vari, Term[] args)
1577 foreach (Term arg in args)
1579 List<Term> list = arg.Listval;
1580 Term result = list[0].Eval (domain);
1584 for (int i = 1; i < list.Count; i++)
1587 result = list[i].Eval (domain);
1598 private static Term Fforeach (Domain domain, Variable vari,
1601 Term result = args[0].Eval (domain);
1604 List<Term> list = result.Listval;
1605 Bindings current = domain.bindings;
1608 domain.Catch (CatchTag.Break);
1609 foreach (Term term in list)
1611 domain.Bind (vari, term);
1613 for (int i = 1; i < args.Length; i++)
1615 result = args[i].Eval (domain);
1620 domain.UnboundTo (current);
1629 private static Term Fquote (Domain domain, Variable vari, Term[] args)
1631 return new Term (args[0]);
1634 private static Term Ftype (Domain domain, Variable vari, Term[] args)
1640 if (args[0].IsSymbol)
1647 public static Term Fcatch (Domain domain, Variable vari, Term[] args)
1651 domain.Catch (new CatchTag (args[0].Symval));
1652 result = args[1].Eval (domain);
1659 public static Term Fthrow (Domain domain, Variable vari, Term[] args)
1661 domain.ThrowTag (new CatchTag (args[0].Symval));
1662 return (args.Length == 1 ? Zero : args[1]);
1665 public delegate TermValue TermParser (Domain domain, XmlNode node);
1667 public class TermType
1669 private readonly Symbol name;
1670 private readonly TermParser parser;
1672 public TermType (Symbol name, TermParser parser)
1675 this.parser = parser;
1678 public Symbol Name { get { return name; } }
1679 internal TermParser Parser { get { return parser; } }
1682 public abstract class TermValue
1684 public virtual Term Eval (Domain domain) { return new Term (this); }
1685 public virtual TermValue Clone () { return this; }
1688 private class Varref : TermValue
1690 private Symbol vname;
1691 private Variable vari;
1693 public Varref (Symbol vname) { this.vname = vname; }
1695 public override Term Eval (Domain domain)
1697 if (vari == null || vari.domain != domain)
1698 vari = domain.GetVar (vname, true);
1702 internal static TermValue parser (Domain domain, XmlNode node)
1704 return new Varref ((Symbol) node.Attributes[Qvname].Value);
1707 public override string ToString ()
1709 return "<varref vname=\"" + vname + "\"/>";
1713 private class Funcall : TermValue
1715 private static Symbol name = "funcall";
1717 public static Symbol Name { get { return name; } }
1719 internal Function func;
1720 internal Variable vari;
1721 internal Term[] args;
1723 public Funcall (Function func, Variable vari, Term[] args)
1727 int nargs = args.Length;
1728 if (nargs < func.min_arg
1729 || (func.max_arg >= 0 && nargs > func.max_arg))
1730 throw_exception ("Invalid number of arguments to {0}: ",
1738 public static TermValue Parser (Domain domain, XmlNode node)
1743 internal static TermValue parser (Domain domain, XmlNode node)
1745 Symbol fname = node.Name;
1748 if (fname == Qfuncall)
1749 fname = node.Attributes[Qfname].Value;
1750 Function func = domain.GetFunc (fname);
1752 attr = node.Attributes[Qvname];
1753 vari = attr == null ? null : domain.GetVar (attr.Value, true);
1754 XmlNodeList nlist = node.ChildNodes;
1755 int nargs = nlist.Count;
1756 Term[] args = new Term[nargs];
1757 for (int i = 0; i < nargs; i++)
1758 args[i] = new Term (domain, nlist[i]);
1759 return new Funcall (func, vari, args);
1762 public override Term Eval (Domain domain)
1764 domain.DebugWrite (ToString ());
1766 Term result = func.Call (domain, vari, args);
1768 domain.DebugWrite ("=> {0}", result.ToString ());
1772 public override TermValue Clone ()
1774 return new Funcall (func, vari, args);
1777 public override string ToString ()
1779 string str = "<" + func.name;
1781 str += " vname=\"" + vari.name + "\"";
1785 if (func is Function.SpecialForm)
1787 for (int i = 0; i < args.Length; i++)
1791 foreach (Term e in args)
1793 return (str + "</" + func.name + ">");
1800 public object objval;
1802 // <integer>...</integer>
1803 public Term (int i) { intval = i; objval = null; }
1804 // <symbol>...</symbol>
1805 public Term (Symbol name) { intval = 0; objval = name; }
1806 // <string>...</string>
1807 public Term (string str) { intval = 0; objval = str; }
1809 public Term (List<Term> list) { intval = 0; objval = list; }
1811 public Term (Term term) { intval = term.intval; objval = term.objval; }
1812 public Term (TermValue obj) { intval = 0; objval = obj; }
1814 public Term (Domain domain, XmlNode node)
1816 Symbol name = node.Name;
1818 if (name == Qinteger)
1820 intval = parse_integer (node.InnerText);
1826 if (name == Qsymbol)
1827 objval = (Symbol) node.InnerText;
1828 else if (name == Qstring)
1829 objval = node.InnerText.Clone ();
1830 else if (name == Qlist)
1832 List<Term> list = new List<Term> ();
1833 for (node = node.FirstChild; node != null;
1834 node = node.NextSibling)
1835 list.Add (new Term (domain, node));
1842 if (domain.termtypes.TryGetValue (name, out term_type))
1843 objval = term_type.Parser (domain, node);
1846 Funcall funcall = (Funcall) Funcall.parser (domain, node);
1847 if (funcall.func is Function.Macro)
1849 Term result = funcall.Eval (domain);
1850 intval = result.intval;
1851 objval = result.objval;
1860 // <varref vname="VNAME"/>
1861 public Term (Domain domain, Symbol vname)
1864 objval = new Varref (vname);
1867 // <funcall fname="FNAME">...</funcall>
1868 public Term (Domain domain, Symbol fname, Term[] args)
1869 : this (domain, fname, Qnull, args) { }
1871 // <funcall fname="FNAME" vname="VNAME">...</funcall>
1872 public Term (Domain domain, Symbol fname, Symbol vname, Term[] args)
1876 Function func = domain.GetFunc (fname);
1877 Variable vari = vname == Qnull ? null : domain.GetVar (vname, true);
1878 Funcall funcall = new Funcall (func, vari, args);
1879 if (func is Function.Macro)
1881 Term result = funcall.Eval (domain);
1882 intval = result.intval;
1883 objval = result.objval;
1889 public object Objval {
1892 throw new Exception ("term is an integer: " + this);
1900 throw new Exception ("term is not integer: " + this);
1905 public string Strval {
1908 throw new Exception ("term is not string: " + this);
1909 return (string) objval;
1913 public string Symval {
1916 throw new Exception ("term is not symbol: " + this);
1917 return (Symbol) objval;
1921 public List<Term> Listval {
1924 throw new Exception ("term is not list: " + this);
1925 return (List<Term>) objval;
1929 public bool IsTrue {
1931 return (objval == null
1933 : objval is List<Term>
1934 ? (((List<Term>) objval).Count != 0)
1938 public bool IsInt { get { return (objval == null); } }
1939 public bool IsStr { get { return (objval is string); } }
1940 public bool IsSymbol { get { return (objval is Symbol); } }
1941 public bool IsList { get { return (objval is List<Term>); } }
1943 public bool IsType (Type type)
1945 return (objval == null ? type == typeof (int)
1946 : type == objval.GetType ());
1949 public Term Eval (Domain domain)
1951 if (objval == null || objval is Symbol || objval is string)
1953 if (objval is List<Term>)
1954 return new Term ((List<Term>) objval);
1955 return ((TermValue) objval).Eval (domain);
1958 public Term Clone ()
1960 if (objval == null || objval is Symbol || objval is string)
1962 if (objval is List<Term>)
1964 List<Term> list = new List<Term> ();
1965 list.InsertRange (0, ((List<Term>) objval));
1966 return new Term (list);
1968 return new Term (((TermValue) objval).Clone ());
1971 public override string ToString ()
1976 str = "<integer>" + intval + "</integer>";
1977 else if (objval is Symbol)
1978 str = "<symbol>" + objval + "</symbol>";
1979 else if (objval is string)
1980 str = "<string>" + objval + "</string>";
1981 else if (objval is List<Term>)
1984 foreach (Term e in (List<Term>) objval)
1988 else if (objval is Term)
1989 str = "<quote>" + objval + "</quote>";
1990 else if (objval is TermValue)
1991 str = ((TermValue) objval).ToString ();
1993 throw new Exception ("invalid Term object: " + objval);
1998 static private Term Zero = new Term (0);
1999 static private Term One = new Term (1);
2000 static private Term TermInt = new Term (Qinteger);
2001 static private Term TermStr = new Term (Qstring);
2002 static private Term TermSymbol = new Term (Qsymbol);
2003 static private Term TermList = new Term (Qlist);
2004 static private Term TermTerm = new Term ((Symbol) "term");
2006 internal static int parse_integer (string str)
2008 int len = str.Length;
2009 bool negative = false;
2012 return (len == 0 ? 0 : str[0] - '0');
2019 if ((c == '0' || c == '#') && str[1] == 'x')
2022 for (int idx = 2; idx < len; idx++)
2028 i = i * 16 + (c - '0');
2032 i = i * 16 + (c - 'A');
2036 i = i * 16 + (c - 'a');
2045 for (int idx = 1; idx < len; idx++)
2048 if (c < '0' || c > '9')
2050 i = i * 10 + (c - '0');
2052 return negative ? - i : i;
2055 private Term[] terms;
2057 public static Term[] ParseTerms (Domain domain, XmlNode node)
2060 for (XmlNode n = node; n != null; n = n.NextSibling)
2061 if (n.NodeType == XmlNodeType.Element)
2063 if (n.Name == Qdefun)
2064 domain.Defun (n, true);
2065 else if (n.Name == Qdefmacro)
2066 domain.Defmacro (n, true);
2067 else if (n.Name == Qdefvar)
2072 Term[] terms = new Term[nterms];
2074 for (XmlNode n = node; n != null; n = n.NextSibling)
2075 if (n.NodeType == XmlNodeType.Element)
2077 if (n.Name == Qdefun)
2078 domain.Defun (n, false);
2079 else if (n.Name == Qdefmacro)
2080 domain.Defmacro (n, false);
2081 else if (n.Name != Qdefvar)
2082 terms[i++]= new Term (domain, n);
2087 public static Term Eval (Domain domain, Term[] terms)
2089 Term result = new Term (0);
2090 foreach (Term term in terms)
2093 if (result.Objval is Funcall)
2094 while ((result = result.Eval (domain)).Objval is Funcall);
2100 public Xexpression (Domain domain, XmlNode node)
2102 terms = ParseTerms (domain, node);
2105 public Xexpression (Domain domain, string url)
2107 XmlDocument doc = new XmlDocument (Symbol.NameTable);
2110 using (XmlTextReader reader = new XmlTextReader (url, doc.NameTable))
2114 } while (reader.NodeType != XmlNodeType.None
2115 && (reader.NodeType != XmlNodeType.Element
2116 || reader.Name != Qexpr));
2117 if (reader.NodeType == XmlNodeType.None)
2118 throw new Exception ("Node <expr> not found");
2119 node = doc.ReadNode (reader);
2121 terms = ParseTerms (domain, node.FirstChild);
2124 public Term Eval (Domain domain)
2130 domain.Catch (CatchTag.Return);
2131 foreach (Term term in terms)
2133 result = term.Eval (domain);
2143 public override string ToString ()
2146 for (int i = 0; i < terms.Length; i++)