namespace System.Xml.Expression
{
- public class Xex
+ public class Xexpression
{
- public struct Name : IEquatable<Name>
+ public static int debug_level = 0;
+
+ public struct Symbol : IEquatable<Symbol>
{
private static NameTable nt = new NameTable ();
- private string name;
+ internal string name;
- public Name (string str)
+ public Symbol (string str)
{
name = nt.Add (str);
}
- public static implicit operator Name (string str)
+ public static implicit operator Symbol (string str)
{
- return new Name (str);
+ return new Symbol (str);
}
- public static implicit operator string (Name name)
+ public static implicit operator string (Symbol name)
{
return name.name;
}
- public static bool operator== (Name n1, Name n2)
+ public static bool operator== (Symbol n1, Symbol n2)
{
return (object) n1.name == (object) n2.name;
}
- public static bool operator!= (Name n1, Name n2)
+ public static bool operator!= (Symbol n1, Symbol n2)
{
return (object) n1.name != (object) n2.name;
}
- public static bool operator== (Name n1, string n2)
+ public static bool operator== (Symbol n1, string n2)
{
return (object) n1.name == (object) n2;
}
- public static bool operator!= (Name n1, string n2)
+ public static bool operator!= (Symbol n1, string n2)
{
return (object) n1.name != (object) n2;
}
- public bool Equals (Name name)
+ public static bool operator== (string n1, Symbol n2)
+ {
+ return (object) n1 == (object) n2.name;
+ }
+
+ public static bool operator!= (string n1, Symbol n2)
+ {
+ return (object) n1 != (object) n2.name;
+ }
+
+ public bool Equals (Symbol name)
{
return Object.ReferenceEquals (this.name, name.name);
}
public override string ToString () { return name; }
}
- private static Name Nexpr = "expr";
- private static Name Ntype = "type";
- private static Name Nargs = "args";
-
- private static Name Ninteger = "integer";
- private static Name Nstring = "string";
- private static Name Nboolean = "boolean";
- private static Name Nsymbol = "symbol";
- private static Name Nlist = "list";
- private static Name Nobject = "object";
-
- private static Name Ndefun = "defun";
- private static Name Ndefmacro = "defmacro";
- private static Name Ndefvar = "defvar";
- private static Name Nconst = "const";
- private static Name Nvariable = "variable";
- private static Name Ndescription = "description";
- private static Name Npossible_value = "possible-value";
-
- private static Name Nfuncall = "funcall";
- private static Name Nmname = "mname";
- private static Name Nprogn = "progn";
-
- internal class Function
+ private static Symbol Qexpr = "expr";
+
+ private static Symbol Qnull = "";
+ private static Symbol Qfuncall = "funcall";
+ private static Symbol Qvarref = "varref";
+ private static Symbol Qinteger = "integer";
+ private static Symbol Qstring = "string";
+ private static Symbol Qsymbol = "symbol";
+ private static Symbol Qlist = "list";
+
+ private static Symbol Qdefun = "defun";
+ private static Symbol Qfname = "fname";
+ private static Symbol Qargs = "args";
+ private static Symbol Qargs_unevalled = "args-unevalled";
+ private static Symbol Qfixed = "fixed";
+ private static Symbol Qoptional = "optional";
+ private static Symbol Qrest = "rest";
+
+ private static Symbol Qdefvar = "defvar";
+ private static Symbol Qvname = "vname";
+ private static Symbol Qdescription = "description";
+ private static Symbol Qrange = "range";
+
+ public abstract class Function
{
- internal class Lambda
- {
- internal Variable[] args;
- internal Xex[] body;
-
- public Lambda (XmlNode node, Domain domain)
- {
- Set (node, domain);
- }
-
- public void Set (XmlNode node, Domain domain)
- {
- XmlNodeList body = node.ChildNodes;
- int idx = 0;
-
- if (Nargs == body[0].Name)
- {
- XmlNodeList args = body[0].ChildNodes;
- if (this.args == null)
- this.args = new Name[args.Count];
- for (int i = 0; i < args.Count; i++)
- this.args[i] = args[i].InnerText;
- idx++;
- }
- else if (this.args == null)
- this.args = new Name[0];
- if (this.body == null)
- this.body = new Xex[body.Count - idx];
- for (int i = 0; idx < body.Count; i++, idx++)
- this.body[i] = new Xex (body[idx], domain);
- }
- }
-
- public readonly Name name;
- public Builtin builtin;
+ public Symbol name;
public int min_arg, max_arg;
- internal Lambda lambda;
- public bool specialp = false;
- public Function (Name name, Builtin builtin,
- int min_arg, int max_arg, bool specialp)
+ public Function () { }
+
+ public Function (Symbol name, int min_arg, int max_arg)
{
this.name = name;
- this.builtin = builtin;
this.min_arg = min_arg;
this.max_arg = max_arg;
- this.specialp = specialp;
}
- internal Function (Name name, XmlNode node, Domain domain)
- {
- this.name = name;
- lambda = new Lambda (node, domain);
- this.min_arg = this.max_arg = lambda.args.Length;
- }
+ public abstract Term Call (Domain domain, Variable vari, Term[] args);
- internal Function (Name name, int nargs, bool specialp)
+ public override string ToString ()
{
- this.name = name;
- this.min_arg = this.max_arg = nargs;
+ return name;
}
- public object Call (Xex[] args, Domain domain)
+ internal class Subroutine : Function
{
- Bindings current = domain.bindings;
- object result = false;
-
- Console.Write ("calling (" + this + "(");
- try {
- if (! specialp)
- foreach (Xex e in args)
- e.Eval (domain);
- Console.WriteLine (")");
- if (builtin != null)
- return builtin (args, domain);
- if (lambda == null)
- return null;
+ public Builtin builtin;
+ public bool setvar;
+
+ public Subroutine (Builtin builtin, Symbol name, bool setvar,
+ int min_arg, int max_arg)
+ : base (name, min_arg, max_arg)
+ {
+ this.builtin = builtin;
+ this.setvar = setvar;
+ }
+
+ public override Term Call (Domain domain, Variable vari, Term[] args)
+ {
+ args = (Term[]) args.Clone ();
for (int i = 0; i < args.Length; i++)
- domain.Bind (bindings, lambda.args[i], args[i].val);
- foreach (Xex e in lambda.body)
{
- result = e.Eval (domain);
- Console.WriteLine (e.ToString () + "=>" + result);
+ args[i] = args[i].Eval (domain);
+ if (domain.Thrown)
+ return args[i];
}
- } finally {
- Console.WriteLine (")");
- domain.UnboundTo (current);
+ return builtin (domain, vari, args);
}
- return result;
}
- public override string ToString ()
+ internal class SpecialForm : Function
{
- return name;
+ public Builtin builtin;
+
+ public SpecialForm (Builtin builtin, Symbol name,
+ int min_arg, int max_arg)
+ : base (name, min_arg, max_arg)
+ {
+ this.builtin = builtin;
+ }
+
+ public override Term Call (Domain domain, Variable vari, Term[] args)
+ {
+ return builtin (domain, vari, args);
+ }
+ }
+
+ internal class Lambda : Function
+ {
+ internal bool args_evalled;
+ internal Variable[] args;
+ internal Term[] body;
+
+ public Lambda (Domain domain, XmlNode node)
+ {
+ int nfixed = 0;
+ int noptional = 0;
+ int nrest = 0;
+ name = node.Attributes[Qfname].Value;
+
+ node = node.FirstChild;
+ if (node != null
+ && (node.Name == Qargs || node.Name == Qargs_unevalled))
+ {
+ XmlNode n;
+ args_evalled = node.Name == Qargs;
+ for (n = node.FirstChild; n != null; n = n.NextSibling)
+ {
+ if (n.Name == Qfixed)
+ nfixed++;
+ else if (n.Name == Qoptional)
+ noptional++;
+ else if (n.Name == Qrest)
+ nrest++;
+ else
+ throw new Exception ("Invalid argument type: " + n);
+ }
+ min_arg = nfixed;
+ max_arg = nfixed + noptional + nrest;
+ args = new Variable[max_arg];
+ n = node.FirstChild;
+ for (int i = 0; i < max_arg; n = n.NextSibling)
+ args[i++] = domain.Defvar ((Symbol) n.Attributes[0].Value);
+ if (nrest == 1)
+ max_arg = - max_arg;
+ }
+ else
+ {
+ min_arg = max_arg = 0;
+ }
+ }
+
+ public Lambda (Domain domain, Symbol name, bool args_evalled, Symbol[] args)
+ {
+ int nfixed = 0;
+ int noptional = 0;
+ int nrest = 0;
+
+ this.name = name;
+ this.args_evalled = args_evalled;
+ if (args != null)
+ {
+ int i = 0;
+ for (i = 0; i < args.Length; i++, nfixed++)
+ if (args[i] == Qoptional || args[i] == Qrest)
+ break;
+ if (i < args.Length)
+ {
+ if (args[i] == Qoptional)
+ {
+ for (i++; i < args.Length; i++, noptional++)
+ if (args[i] == Qrest)
+ break;
+ if (i < args.Length)
+ nrest = 1;
+ }
+ }
+ min_arg = nfixed;
+ max_arg = nfixed + noptional + nrest;
+ this.args = new Variable[max_arg];
+ int j;
+ for (i = j = 0; j < this.args.Length; i++)
+ if (args[i] != Qoptional || args[i] != Qrest)
+ this.args[j++] = domain.Defvar (args[i]);
+ }
+ else
+ {
+ min_arg = max_arg = 0;
+ }
+ }
+
+ public void SetBody (Domain domain, XmlNode node)
+ {
+ for (node = node.FirstChild; node != null; node = node.NextSibling)
+ if (node.Name != Qdescription
+ && node.Name != Qargs
+ && node.Name != Qargs_unevalled)
+ break;
+ int nterms = 0;
+ for (XmlNode n = node; n != null; n = n.NextSibling)
+ nterms++;
+ if (nterms > 0)
+ {
+ body = new Term[nterms];
+ for (nterms = 0; node != null; node = node.NextSibling, nterms++)
+ body[nterms] = new Term (domain, node);
+ }
+ }
+
+ public void SetBody (Term[] body)
+ {
+ this.body = body;
+ }
+
+ public override Term Call (Domain domain, Variable vari, Term[] args)
+ {
+ Bindings current = domain.bindings;
+ Term result = Zero;
+
+ try {
+ int i;
+ if (args_evalled)
+ {
+ Term[] newargs = new Term[args.Length];
+ for (i = 0; i < min_arg; i++)
+ newargs[i] = args[i].Eval (domain);
+ args = newargs;
+ }
+ for (i = 0; i < min_arg; i++)
+ domain.Bind (this.args[i], args[i]);
+ if (body != null)
+ {
+ try {
+ if (args_evalled)
+ domain.Catch (CatchTag.Return);
+ foreach (Term term in body)
+ {
+ result = term.Eval (domain);
+ if (domain.Thrown)
+ return result;
+ }
+ } finally {
+ if (args_evalled)
+ domain.Uncatch ();
+ }
+ }
+ } finally {
+ domain.UnboundTo (current);
+ }
+ return result;
+ }
}
}
- internal abstract class Variable
+ public class Variable : TermValue
{
- public readonly Name name;
- public readonly Name type;
- internal object val;
+ public readonly Symbol name;
+ public string desc;
+ internal Term default_val;
+ internal Term val;
+ object range;
- public Variable (Name name, Name type, object value)
+ public Variable (Symbol name, Term value)
{
this.name = name;
- this.type = type;
val = value;
+ default_val = Zero;
}
- public object Value
+ public virtual bool ValueP (Term val) { return true; }
+
+ public override TermValue Clone ()
{
- get { return val; }
- set
- {
- if (! ValueP (value))
- throw new Exception ("Invalid value type: " + value);
- val = value;
- }
+ Variable v = new Variable (name, val);
+ v.desc = desc;
+ v.default_val = default_val;
+ v.range = range;
+ return v;
}
- public abstract bool ValueP (object value);
+ public Term Value
+ {
+ get { return val; }
+ set {
+ if (! ValueP (value))
+ throw new Exception ("Invalid value: " + value);
+ val = value;
+ }
+ }
- public override string ToString () { return name + "(" + type + ")"; }
- }
+ public Term DefaultValue
+ {
+ get { return default_val; }
+ set {
+ if (! ValueP (value))
+ throw new Exception ("Invalid value: " + value);
+ default_val = value;
+ }
+ }
- internal class VarInt : Variable
- {
- public struct Range
+ public virtual object Range
{
- public int from, to;
+ get { return range; }
+ set { range = value; }
}
- public Range[] ranges;
+ public override Term Eval (Domain domain) { return val; }
- public VarInt (Name name, int value) : base (name, Ninteger, value) { }
+ public override string ToString () { return name + "(" + val + ")"; }
- public override bool ValueP (object value)
+ public class Int : Variable
{
- int i;
-
- if (! (value is int))
- return false;
- if (ranges == null)
- return true;
- i = (int) value;
- foreach (Range r in ranges)
- if (i >= r.from && i <= r.to)
+ public int[] range;
+
+ private static bool SubsetP (int[] r1, int[] r2)
+ {
+ if (r2 == null)
+ return true;
+ for (int i = 0; i < r1.Length; i += 2)
+ {
+ int j;
+ for (j = 0; j < r2.Length; j += 2)
+ if (r2[j] <= r1[i] && r2[j + 1] >= r1[i + 1])
+ break;
+ if (j >= r2.Length)
+ return false;
+ }
return true;
- return false;
- }
- }
+ }
- internal class VarStr : Variable
- {
- public string[] ranges;
+ private static bool SubsetP (int val, int[] r)
+ {
+ if (r == null)
+ return true;
+ for (int i = 0; i < r.Length; i += 2)
+ if (r[i] <= val && r[i + 1] >= val)
+ return true;
+ return false;
+ }
+
+ public Int (Symbol name, string description, int value, int[] range)
+ : base (name, new Term (value))
+ {
+ if (! SubsetP (value, range))
+ throw new Exception ("Invalid value: " + value);
+ desc = description;
+ default_val = val;
+ this.range = range;
+ }
+
+ public override bool ValueP (Term term)
+ {
+ if (! term.IsInt)
+ return false;
+ return SubsetP (term.Intval, range);
+ }
- public VarStr (Name name, string value) : base (name, Nstring, value) { }
+ public override object Range {
+ get { return range; }
+ set {
+ int[] r = (int[]) value;
+ if (! SubsetP (r, range)
+ || ! SubsetP (val.Intval, r)
+ || ! SubsetP (default_val.Intval, r))
+ throw new Exception ("Invalid range");
+ range = r;
+ }
+ }
+ }
- public override bool ValueP (object value)
+ public class Str : Variable
{
- string str;
+ public string[] range;
- if (! (value is string))
- return false;
- if (ranges == null)
- return true;
- str = (string) value;
- foreach (string s in ranges)
- if (s == str)
+ private static bool SubsetP (string[] r1, string[] r2)
+ {
+ if (r2 == null)
+ return true;
+ foreach (string s in r1)
+ if (! SubsetP (s, r2))
+ return false;
return true;
- return false;
- }
- }
+ }
- internal class VarBool : Variable
- {
- public VarBool (Name name, bool value) : base (name, Nboolean, value) { }
+ private static bool SubsetP (string str, string[] r)
+ {
+ if (r == null)
+ return true;
+ foreach (string s in r)
+ if (str == s)
+ return true;
+ return false;
+ }
- public override bool ValueP (object value)
- {
- return value is bool;
- }
- }
+ public Str (Symbol name, string description, string value, string[] range)
+ : base (name, new Term (value))
+ {
+ if (! SubsetP (value, range))
+ throw new Exception ("Invalid value: " + value);
+ desc = description;
+ default_val = val;
+ this.range = range;
+ }
- internal class VarMisc : Variable
- {
- public VarMisc (Name name, object value) : base (name, Nobject, value) { }
+ public override bool ValueP (Term term)
+ {
+ if (! (term.objval is string))
+ return false;
+ return SubsetP (term.Strval, range);
+ }
+
+ public override object Range {
+ get { return range; }
+ set {
+ string[] r = (string[]) value;
+ if (! SubsetP (r, range)
+ || ! SubsetP (val.Strval, r)
+ || ! SubsetP (default_val.Strval, r))
+ throw new Exception ("Invalid range");
+ range = r;
+ }
+ }
+ }
- public override bool ValueP (object value)
+ public class Sym : Variable
{
- return true;
+ public Symbol[] range;
+
+ private static bool SubsetP (Symbol[] r1, Symbol[] r2)
+ {
+ if (r2 == null)
+ return true;
+ foreach (Symbol n in r1)
+ if (! SubsetP (n, r2))
+ return false;
+ return true;
+ }
+
+ private static bool SubsetP (Symbol name, Symbol[] r)
+ {
+ if (r == null)
+ return true;
+ foreach (Symbol n in r)
+ if (name == n)
+ return true;
+ return false;
+ }
+
+ public Sym (Symbol name, string description, Symbol value, Symbol[] range)
+ : base (name, new Term (value))
+ {
+ if (! SubsetP (value, range))
+ throw new Exception ("Invalid value: " + value);
+ desc = description;
+ default_val = val;
+ this.range = range;
+ }
+
+ public override bool ValueP (Term term)
+ {
+ if (! (term.objval is Symbol))
+ return false;
+ return SubsetP (term.Symval, range);
+ }
+
+ public override object Range {
+ get { return range; }
+ set {
+ Symbol[] r = (Symbol[]) value;
+ if (! SubsetP (r, range)
+ || ! SubsetP (val.Symval, r)
+ || ! SubsetP (default_val.Symval, r))
+ throw new Exception ("Invalid range");
+ range = r;
+ }
+ }
}
}
internal class Bindings
{
private Variable vari;
- private object old_value;
+ private Term old_value;
private Bindings next;
- private Bindings (Variable vari, object value)
+ private Bindings (Variable vari)
{
this.vari = vari;
- old_value = value;
+ old_value = vari.val;
}
- public static Bindings Bind (Bindings bindings,
- Variable vari, object value)
+ public static Bindings Bind (Bindings bindings, Variable vari, Term val)
{
- Bindings b = new Bindings (vari, vari.val);
+ Bindings b = new Bindings (vari);
- b.vari.Value = value;
+ b.vari.Value = val;
b.next = bindings;
return b;
}
internal Bindings UnboundTo (Bindings boundary)
{
for (Bindings b = this; b != boundary; b = b.next)
- vari.val = b.old_value;
+ b.vari.val = b.old_value;
return boundary;
}
{
string str = "(bindings";
for (Bindings b = this; b != null; b = b.next)
- str += " " + vari;
+ str += " " + vari.name + "=" + b.old_value;
return str + ")";
}
}
#if false
internal class ThrowException : Exception
{
- Name tag;
+ Symbol tag;
public object value;
- public ThrowException (Name tag, object value) : base ()
+ public ThrowException (Symbol tag, object value) : base ()
{
this.tag = tag;
this.value = value;
}
#endif
+ internal class CatchTag : IEquatable<CatchTag>
+ {
+ private object val;
+
+ public CatchTag (Symbol name) { val = name.name; }
+ private CatchTag (int i) { val = i; }
+
+ public static CatchTag Return = new CatchTag (0);
+ public static CatchTag Break = new CatchTag (1);
+
+ public static bool operator== (CatchTag t1, CatchTag t2)
+ { return t1.val == t2.val; }
+
+ public static bool operator!= (CatchTag t1, CatchTag t2)
+ { return t1.val != t2.val; }
+
+ public bool Equals (CatchTag tag) { return this.val == tag.val; }
+ public override bool Equals (object val) { return this.val == val; }
+
+ public override int GetHashCode () { return val.GetHashCode (); }
+ }
+
public class Domain
{
- private Domain parent;
public object context;
-
- internal Dictionary<Name, Function> functions
- = new Dictionary<Name, Function> ();
- internal Dictionary<Name, Variable> variables
- = new Dictionary<Name, Variable> ();
+ public int depth = 0;
+
+ internal Dictionary<Symbol, TermType> termtypes
+ = new Dictionary<Symbol, TermType> ();
+ internal Dictionary<Symbol, Function> functions
+ = new Dictionary<Symbol, Function> ();
+ internal Dictionary<Symbol, Variable> variables
+ = new Dictionary<Symbol, Variable> ();
internal Bindings bindings;
+ private Stack<CatchTag> catch_stack = new Stack<CatchTag> ();
+ private int catch_count = 0;
internal Domain () { }
- public Domain (object context) : this (basic, context)
- {
- }
+ public Domain (object context) : this (basic, context) { }
public Domain (Domain parent, object context)
{
- this.parent = parent;
+ termtypes = new Dictionary<Symbol, TermType> (parent.termtypes);
+ functions = new Dictionary<Symbol, Function> (parent.functions);
+ variables = new Dictionary<Symbol, Variable> (parent.variables);
this.context = context;
}
- internal void Bind (Variable vari, object value)
+ internal void Bind (Variable vari, Term value)
{
bindings = Bindings.Bind (bindings, vari, value);
}
internal void UnboundTo (Bindings boundary)
{
- if (boundary != null)
+ if (bindings != null)
bindings = bindings.UnboundTo (boundary);
}
- public void Defun (Name name, Builtin builtin, int min_arg, int max_arg)
+ internal void Catch (CatchTag tag)
{
- Defun (name, builtin, min_arg, max_arg, false);
+ catch_stack.Push (tag);
+ catch_count++;
}
- public void Defun (Name name, Builtin builtin, int min_arg, int max_arg,
- bool specialp)
+ internal void Uncatch ()
{
- Function func;
+ catch_stack.Pop ();
+ if (catch_count > catch_stack.Count)
+ catch_count--;
+ }
- if (functions.TryGetValue (name, out func))
+ public bool Thrown {
+ get { return catch_count < catch_stack.Count; }
+ }
+
+ internal void ThrowReturn ()
+ {
+ foreach (CatchTag tag in catch_stack)
{
- if (func.min_arg < min_arg || func.max_arg > max_arg)
- throw new Exception ("Incompatible argument numbers to override: "
- + name);
- func.builtin = builtin;
- func.lambda = null;
- func.min_arg = min_arg;
- func.max_arg = max_arg;
- func.specialp = specialp;
+ catch_count--;
+ if (tag == CatchTag.Return)
+ break;
}
- else
+ }
+
+ internal void ThrowBreak ()
+ {
+ if (catch_stack.Peek () != CatchTag.Break)
+ throw new Exception ("No outer loop to break");
+ catch_count--;
+ }
+
+ internal void ThrowTag (CatchTag tag)
+ {
+ foreach (CatchTag elt in catch_stack)
{
- functions[name]
- = new Function (name, builtin, min_arg, max_arg, specialp);
+ catch_count--;
+ if (elt == tag)
+ break;
}
}
- public void Defun (XmlNode node)
+ public void DefTerm (Symbol name, TermParser parser)
+ {
+ termtypes[name] = new TermType (name, parser);
+ }
+
+ public void DefSubr (Builtin builtin, string str, bool setvar,
+ int min_arg, int max_arg, params string[] aliases)
+ {
+ Symbol name = str;
+ Function func = new Function.Subroutine (builtin, name, setvar,
+ min_arg, max_arg);
+ functions[name] = func;
+ foreach (string a in aliases)
+ functions[(Symbol) a] = func;
+ }
+
+ public void DefSpecial (Builtin builtin, string str,
+ int min_arg, int max_arg,
+ params string[] aliases)
+ {
+ Symbol name = str;
+ Function func = new Function.SpecialForm (builtin, name,
+ min_arg, max_arg);
+ functions[name] = func;
+ foreach (string a in aliases)
+ functions[(Symbol) a] = func;
+ }
+
+ public void DefAlias (string alias, string str)
+ {
+ functions[(Symbol) alias] = functions[(Symbol) str];
+ }
+
+ public void Defun (Symbol name, bool args_evalled,
+ Symbol[] args, Term[] body, bool prototype)
{
- Name name = node.Attributes[0].Value;
Function func;
- if (functions.TryGetValue (name, out func))
- {
- XmlNode args = node.FirstChild;
- int nargs = args.Name == Nargs ? args.ChildNodes.Count : 0;
-
- if (func.min_arg < nargs || func.max_arg > nargs)
- throw new Exception ("Incompatible argument numbers to override: "
- + name);
- if (func.lambda == null)
- func.lambda = new Function.Lambda (node, this);
- else
- func.lambda.Set (node, this);
- func.builtin = null;
- }
- else
+ if (prototype || ! functions.TryGetValue (name, out func))
{
- func = new Function (name, node, this);
+ func = new Function.Lambda (this, name, args_evalled, args);
functions[name] = func;
- }
+ }
+ if (! prototype)
+ ((Function.Lambda) func).SetBody (body);
}
- public void Defun (Name name, int nargs, bool specialp)
+ public void Defun (XmlNode node, bool prototype)
{
+ Symbol name = node.Attributes[Qfname].Value;
Function func;
- if (functions.TryGetValue (name, out func))
- {
- if (func.min_arg < nargs || func.max_arg > nargs)
- throw new Exception ("Incompatible argument numbers to override: "
- + name);
- func.min_arg = func.max_arg = nargs;
- func.specialp = specialp;
- func.builtin = null;
- }
- else
+ if (prototype || ! functions.TryGetValue (name, out func))
{
- func = new Function (name, nargs, specialp);
+ func = new Function.Lambda (this, node);
functions[name] = func;
- }
+ }
+ if (! prototype)
+ ((Function.Lambda) func).SetBody (this, node);
+ }
+
+ public void Defun (Function func)
+ {
+ functions[func.name] = func;
}
- public void Defvar (Name name, XmlNode node)
+ public Variable Defvar (XmlNode node)
{
+ Symbol name = node.Attributes[0].Value;
+ String desc;
Variable vari;
- if (node.Name == Ndescription)
- node = node.NextSibling;
- if (node.Name == Nconst)
+ node = node.FirstChild;
+ if (node != null && node.Name == Qdescription)
+ {
+ desc = node.InnerText;
+ node = node.NextSibling;
+ }
+ else
+ desc = null;
+ if (node != null)
{
- Name type = (Name) node.Attributes[Ntype].Value;
- string val = node.Value;
+ Symbol type = node.Name;
XmlNodeList range_list = null;
int nranges = 0;
+ string val = node.InnerText;
node = node.NextSibling;
- if (node.Name == Npossible_value)
+ if (node != null)
{
range_list = node.ChildNodes;
nranges = range_list.Count;
}
- if (type == Ninteger)
+ if (type == Qinteger)
{
- VarInt vi = new VarInt (name, parse_integer (val));
+ int intval = parse_integer (val);
+ int[] range = null;
if (range_list != null)
{
- vi.ranges = new VarInt.Range[nranges];
-
+ range = new int[nranges * 2];
for (int i = 0; i < nranges; i++)
{
XmlNode n = range_list[i];
-
- if (n.Name == Nconst)
+ if (n.Name == Qrange)
{
- int num = parse_integer (n.Value);
- vi.ranges[i].from = vi.ranges[i].to = num;
+ range[i * 2]
+ = parse_integer (n.FirstChild.InnerText);
+ range[i * 2 + 1]
+ = parse_integer (n.LastChild.InnerText);
}
- else // range_list[i].Name == "range"
+ else
{
- vi.ranges[i].from =
- parse_integer (n.FirstChild.Value);
- vi.ranges[i].to =
- parse_integer (n.LastChild.Value);
+ range[i * 2]
+ = range[i * 2 + 1]
+ = parse_integer (n.FirstChild.InnerText);
}
}
}
- vari = vi;
+
+ if (variables.TryGetValue (name, out vari))
+ {
+ if (! (vari is Variable.Int))
+ throw new Exception ("Inalid value");
+ vari = (Variable) vari.Clone ();
+ Term v = new Term (intval);
+ vari.Value = v;
+ vari.DefaultValue = v;
+ if (range != null)
+ vari.Range = range;
+ }
+ else
+ vari = new Variable.Int (name, desc, intval, range);
}
- else if (type == Nstring)
+ else if (type == Qstring)
{
- VarStr vs = new VarStr (name, val);
+ string[] range = null;
if (range_list != null)
- vs.ranges = new string[nranges];
- for (int i = 0; i < nranges; i++)
- vs.ranges[i] = range_list[i].Value;
- vari = vs;
+ {
+ range = new string[nranges];
+ for (int i = 0; i < nranges; i++)
+ range[i] = range_list[i].FirstChild.InnerText;
+ }
+
+ if (variables.TryGetValue (name, out vari))
+ {
+ if (! (vari is Variable.Str))
+ throw new Exception ("Invalid value");
+ vari = (Variable) vari.Clone ();
+ Term v = new Term (val);
+ vari.Value = v;
+ vari.DefaultValue = v;
+ if (range != null)
+ vari.Range = range;
+ }
+ else
+ vari = new Variable.Str (name, desc, val, range);
}
- else if (type == Nboolean)
+ else if (type == Qsymbol)
{
- vari = new VarBool (name, val == "true");
+ Symbol[] range = null;
+ if (range_list != null)
+ {
+ range = new Symbol[nranges];
+ for (int i = 0; i < nranges; i++)
+ range[i] = range_list[i].FirstChild.InnerText;
+ }
+
+ if (variables.TryGetValue (name, out vari))
+ {
+ if (! (vari is Variable.Sym))
+ throw new Exception ("Invalid value");
+ vari = (Variable) vari.Clone ();
+ Term v = new Term (val);
+ vari.Value = v;
+ vari.DefaultValue = v;
+ if (range != null)
+ vari.Range = range;
+ }
+ else
+ vari = new Variable.Sym (name, desc, val, range);
}
else
throw new Exception ("Unknown type: " + type);
}
else
- vari = new VarMisc (name, null);
+ {
+ if (variables.TryGetValue (name, out vari))
+ vari = (Variable) vari.Clone ();
+ else
+ vari = new Variable (name, Zero);
+ }
+ variables[name] = vari;
+ return vari;
+ }
+
+ public Variable Defvar (Variable vari)
+ {
+ variables[vari.name] = vari;
+ return vari;
+ }
+
+ internal Variable Defvar (Symbol name)
+ {
+ Variable vari = new Variable (name, Zero);
variables[name] = vari;
+ return vari;
}
- internal Function GetFunc (Name name)
+ internal Function GetFunc (Symbol name)
{
Function func;
if (! functions.TryGetValue (name, out func))
- {
- if (parent != null)
- return parent.GetFunc (name);
- throw new Exception ("Unknown function: " + name);
- }
+ throw new Exception ("Unknown function: " + name);
return func;
}
- public bool CopyFunc (Domain domain, Name name)
+ public bool CopyFunc (Domain domain, Symbol name)
{
Function func = GetFunc (name);
public void CopyFunc (Domain domain)
{
- foreach (KeyValuePair<Name, Function> kv in functions)
+ foreach (KeyValuePair<Symbol, Function> kv in functions)
domain.functions[kv.Key] = kv.Value;
}
- internal Variable GetVar (Name name)
+ public Variable GetVar (Symbol name, bool create)
{
Variable vari;
if (! variables.TryGetValue (name, out vari))
- variables[name] = vari = new VarMisc (name, null);
+ {
+ if (! create)
+ return null;
+ variables[name] = vari = new Variable (name, Zero);
+ }
return vari;
}
- internal Variable GetVar (Xex e)
- {
- if (! (e.val is Name))
- throw new Exception ("Not a symbol" + e.val);
- return GetVar ((Name) e.val);
- }
-
public override string ToString ()
{
string str = "<(functions";
- foreach (KeyValuePair<Name, Function> kv in functions)
+ foreach (KeyValuePair<Symbol, Function> kv in functions)
str += " " + kv.Key;
str += ") (variabls";
- foreach (KeyValuePair<Name, Variable> kv in variables)
+ foreach (KeyValuePair<Symbol, Variable> kv in variables)
str += " " + kv.Key;
str += ")";
if (bindings != null)
str += ">";
return str;
}
- }
-
- public delegate object Builtin (Xex[] args, Domain domain);
-
- private static Domain basic = new Domain ();
- internal static Function Fprogn;
+ internal void DebugWrite (bool head, string fmt, params string[] arg)
+ {
+ if (debug_level > depth)
+ {
+ if (head)
+ {
+ Console.WriteLine ();
+ for (int i = 0; i < depth; i++)
+ Console.Write (" ");
+ }
+ Console.Write (fmt, arg);
+ }
+ }
+
+ public object SaveValues ()
+ {
+ Dictionary<Variable,Term> values = new Dictionary<Variable,Term> ();
+
+ foreach (KeyValuePair<Symbol,Variable> kv in variables)
+ values[kv.Value] = kv.Value.val.Clone ();
+ return values;
+ }
+
+ public void RestoreValues (object values)
+ {
+ foreach (KeyValuePair<Variable,Term> kv
+ in (Dictionary<Variable,Term>) values)
+ kv.Key.val = kv.Value;
+ }
+ }
+
+ public delegate Term Builtin (Domain domain, Variable vari, Term[] args);
+
+ private static Domain basic = new Domain ();
+
+ static Xexpression ()
+ {
+ basic.DefTerm ("funcall", Funcall.parser);
+
+ basic.DefSubr (Fset, "set", true, 1, 1, "=");
+ basic.DefSubr (Fnot, "not", false, 1, 1, "!");
+ basic.DefSubr (Fadd, "add", true, 1, -1, "+");
+ basic.DefSubr (Fmul, "mul", true, 1, -1, "*");
+ basic.DefSubr (Fsub, "sub", true, 1, -1, "-");
+ basic.DefSubr (Fdiv, "div", true, 1, -1, "/");
+ basic.DefSubr (Fmod, "mod", true, 1, 2, "%");
+ basic.DefSubr (Flogior, "logior", true, 1, -1, "|");
+ basic.DefSubr (Flogand, "logand", true, 1, -1, "&");
+ basic.DefSubr (Flsh, "lsh", true, 1, 2, "<<");
+ basic.DefSubr (Frsh, "rsh", true, 1, 2, ">>");
+ basic.DefSubr (Feq, "eq", false, 2, -1, "==");
+ basic.DefSubr (Fnoteq, "noteq", false, 2, 2, "!=");
+ basic.DefSubr (Flt, "lt", false, 2, -1, "<");
+ basic.DefSubr (Fle, "le", false, 2, -1, "<=");
+ basic.DefSubr (Fgt, "gt", false, 2, -1, ">");
+ basic.DefSubr (Fge, "ge", false, 2, -1, ">=");
+ basic.DefSubr (Fappend, "append", true, 0, -1);
+ basic.DefSubr (Fconcat, "concat", true, 0, -1);
+ basic.DefSubr (Fnth, "nth", false, 2, 2);
+ basic.DefSubr (Fcopy, "copy", false, 1, 1);
+ basic.DefSubr (Fins, "ins", true, 2, 2);
+ basic.DefSubr (Fdel, "del", true, 2, 2);
+ basic.DefSubr (Feval, "eval", false, 1, 1);
+ basic.DefSubr (Fbreak, "break", false, 0, 1);
+ basic.DefSubr (Freturn, "return", false, 0, 1);
+
+ basic.DefSpecial (Fand, "and", 1, -1, "&&");
+ basic.DefSpecial (For, "or", 1, -1, "||");
+ basic.DefSpecial (Fprogn, "progn", 0, -1, "expr");
+ basic.DefSpecial (Fif, "if", 2, 3);
+ basic.DefSpecial (Fwhen, "when", 1, -1);
+ basic.DefSpecial (Floop, "loop", 1, -1);
+ basic.DefSpecial (Fwhile, "while", 1, -1);
+ basic.DefSpecial (Fcond, "cond", 1, -1);
+ basic.DefSpecial (Fforeach, "foreach", 2, -1);
+ basic.DefSpecial (Fquote, "quote", 1, 1);
+ basic.DefSpecial (Ftype, "type", 1, 1);
+ basic.DefSpecial (Fcatch, "catch", 2, 2);
+ basic.DefSpecial (Fthrow, "throw", 1, 2);
+ }
- static Xex ()
+ private static Term Fset (Domain domain, Variable vari, Term[] args)
{
- basic.Defun ("set", set_value, 2, 2, false);
- basic.Defun ("=", set_value, 2, 2, false);
- basic.Defun ("and", and, 1, -1, false);
- basic.Defun ("&&", and, 1, -1, false);
- basic.Defun ("or", or, 1, -1, false);
- basic.Defun ("||", or, 1, -1, false);
- basic.Defun ("not", not, 1, 1, false);
- basic.Defun ("!", not, 1, 1, false);
- basic.Defun ("add", add, 2, -1, false);
- basic.Defun ("+", add, 2, -1, false);
- basic.Defun ("mul", mul, 2, -1, false);
- basic.Defun ("*", mul, 2, -1, false);
- basic.Defun ("sub", sub, 1, -1, false);
- basic.Defun ("-", sub, 1, -1, false);
- basic.Defun ("div", div, 2, -1, false);
- basic.Defun ("/", div, 2, -1, false);
- basic.Defun ("mod", mod, 2, 2, false);
- basic.Defun ("%", mod, 2, 2, false);
- basic.Defun ("logior", logior, 2, -1, false);
- basic.Defun ("|", logior, 2, -1, false);
- basic.Defun ("logand", logand, 2, -1, false);
- basic.Defun ("&", logand, 2, -1, false);
- basic.Defun ("add-set", add_set, 2, -1, true);
- basic.Defun ("+=", add_set, 2, -1, true);
- basic.Defun ("mul-set", mul_set, 2, -1, true);
- basic.Defun ("*=", mul_set, 2, -1, true);
- basic.Defun ("sub-set", sub_set, 2, -1, true);
- basic.Defun ("-=", sub_set, 2, -1, true);
- basic.Defun ("div-set", div_set, 2, -1, true);
- basic.Defun ("/=", div_set, 2, -1, true);
- basic.Defun ("mod-set", mod_set, 2, 2, true);
- basic.Defun ("%=", mod_set, 2, 2, true);
- basic.Defun ("logior-set", logior_set, 2, -1, true);
- basic.Defun ("|=", logior_set, 2, -1, true);
- basic.Defun ("logand-set", logand_set, 2, -1, true);
- basic.Defun ("&=", logand_set, 2, -1, true);
- basic.Defun ("lsh", lsh, 2, 2, false);
- basic.Defun ("<<", lsh, 2, 2, false);
- basic.Defun ("rsh", rsh, 2, 2, false);
- basic.Defun (">>", rsh, 2, 2, false);
- basic.Defun ("lsh-set", lsh_set, 2, 2, true);
- basic.Defun ("<<=", lsh_set, 2, 2, true);
- basic.Defun ("rsh-set", rsh_set, 2, 2, true);
- basic.Defun (">>=", rsh_set, 2, 2, true);
- basic.Defun ("eq", eq, 2, -1, false);
- basic.Defun ("==", eq, 2, -1, false);
- basic.Defun ("noteq", noteq, 2, 2, false);
- basic.Defun ("!=", noteq, 2, 2, false);
- basic.Defun ("lt", less_than, 2, -1, false);
- basic.Defun ("<", less_than, 2, -1, false);
- basic.Defun ("le", less_eq, 2, -1, false);
- basic.Defun ("<=", less_eq, 2, -1, false);
- basic.Defun ("gt", greater_than, 2, -1, false);
- basic.Defun (">", greater_than, 2, -1, false);
- basic.Defun ("ge", greater_eq, 2, -1, false);
- basic.Defun (">=", greater_eq, 2, -1, false);
- basic.Defun ("progn", progn_clause, 0, -1, true);
- basic.Defun ("expr", progn_clause, 0, -1, true);
- basic.Defun ("if", if_clause, 2, -1, true);
- basic.Defun ("when", when_clause, 1, -1, true);
- basic.Defun ("while", while_clause, 1, -1, true);
-
- Fprogn = basic.GetFunc (Nprogn);
+ vari.Value = args[0];
+ return vari.val;
}
- private static bool is_true (object val)
+ private static Term Fnot (Domain domain, Variable vari, Term[] args)
{
- return (val is bool ? (bool) val
- : val is int ? (int) val == 0
- : true);
+ return args[0].IsTrue ? Zero : One;
}
- private static object set_value (Xex[] args, Domain domain)
+ private static Term Fadd (Domain domain, Variable vari, Term[] args)
{
- Variable vari = domain.GetVar (args[0]);
+ int n = vari == null ? 0 : vari.val.Intval;
- vari.Value = args[1].val;
+ foreach (Term arg in args)
+ n += arg.Intval;
+ if (vari == null)
+ return new Term (n);
+ vari.val.intval = n;
return vari.val;
}
- private static object and (Xex[] args, Domain domain)
+ private static Term Fmul (Domain domain, Variable vari, Term[] args)
{
- foreach (Xex arg in args)
- if (! is_true (arg.val))
- return false;
- return true;
+ int n = vari == null ? 1 : vari.val.Intval;
+ foreach (Term arg in args)
+ n *= arg.Intval;
+ if (vari == null)
+ return new Term (n);
+ vari.val.intval = n;
+ return vari.val;
}
- private static object or (Xex[] args, Domain domain)
+ private static Term Fsub (Domain domain, Variable vari, Term[] args)
{
- foreach (Xex arg in args)
- if (is_true (arg.val))
- return true;
- return false;
+ int n, i;
+
+ if (vari == null)
+ {
+ n = args[0].Intval;
+ i = 1;
+ }
+ else
+ {
+ n = vari.val.Intval;
+ i = 0;
+ }
+ while (i < args.Length)
+ n -= args[i++].Intval;
+ if (vari == null)
+ return new Term (n);
+ vari.val.intval = n;
+ return vari.val;
}
- private static object not (Xex[] args, Domain domain)
+ private static Term Fdiv (Domain domain, Variable vari, Term[] args)
{
- return ! is_true (args[0].val);
+ int n, i;
+
+ if (vari == null)
+ {
+ n = args[0].Intval;
+ i = 1;
+ }
+ else
+ {
+ n = vari.val.Intval;
+ i = 0;
+ }
+ while (i < args.Length)
+ n /= args[i++].Intval;
+ if (vari == null)
+ return new Term (n);
+ vari.val.intval = n;
+ return vari.val;
}
- private static object add (Xex[] args, Domain domain)
+ private static Term Fmod (Domain domain, Variable vari, Term[] args)
{
- int n = 0;
- foreach (Xex e in args)
- n += (int) e.val;
- return n;
+ if (vari == null)
+ return new Term (args[0].Intval % args[1].Intval);
+ vari.val.intval = vari.val.Intval % args[0].Intval;
+ return vari.val;
}
- private static object mul (Xex[] args, Domain domain)
- {
- int n = 1;
- foreach (Xex e in args)
- n *= (int) e.val;
- return n;
- }
+ private static Term Flogior (Domain domain, Variable vari, Term[] args)
+ {
+ int n = vari == null ? 0 : vari.val.Intval;
+ foreach (Term arg in args)
+ n |= arg.Intval;
+ if (vari == null)
+ return new Term (n);
+ vari.val.intval = n;
+ return vari.val;
+ }
- private static object sub (Xex[] args, Domain domain)
- {
- int n = (int) args[0].val;
- if (args.Length == 1)
- return - n;
- for (int i = 1; i < args.Length; i++)
- n -= (int) args[i].val;
- return n;
- }
+ private static Term Flogand (Domain domain, Variable vari, Term[] args)
+ {
+ int n, i;
- private static object div (Xex[] args, Domain domain)
- {
- int n = (int) args[0].val;
- for (int i = 1; i < args.Length; i++)
- n /= (int) args[i].val;
- return n;
- }
+ if (vari == null)
+ {
+ n = args[0].Intval;
+ i = 1;
+ }
+ else
+ {
+ n = vari.val.Intval;
+ i = 0;
+ }
+ while (i < args.Length)
+ n &= args[i++].Intval;
+ if (vari == null)
+ return new Term (n);
+ vari.val.intval = n;
+ return vari.val;
+ }
- private static object mod (Xex[] args, Domain domain)
- {
- return ((int) args[0].val % (int) args[1].val);
- }
+ private static Term Flsh (Domain domain, Variable vari, Term[] args)
+ {
+ if (vari == null)
+ return new Term (args[0].Intval << args[1].Intval);
+ vari.val.intval = vari.val.Intval << args[0].Intval;
+ return vari.val;
+ }
- private static object logior (Xex[] args, Domain domain)
- {
- int n = 0;
- foreach (Xex e in args)
- n |= (int) e.val;
- return n;
- }
+ private static Term Frsh (Domain domain, Variable vari, Term[] args)
+ {
+ if (vari == null)
+ return new Term (args[0].Intval >> args[1].Intval);
+ vari.val.intval = vari.val.Intval >> args[0].Intval;
+ return vari.val;
+ }
- private static object logand (Xex[] args, Domain domain)
- {
- int n = (int) args[0].val;
- for (int i = 1; i < args.Length; i++)
- n &= (int) args[i].val;
- return n;
- }
+ private static Term Feq (Domain domain, Variable vari, Term[] args)
+ {
+ Term o = args[0];
- private static object add_set (Xex[] args, Domain domain)
- {
- Variable vari = domain.GetVar (args[0]);
- int n = (int) vari.val;
+ if (o.objval == null)
+ {
+ for (int i = 1; i < args.Length; i++)
+ if (args[i].objval != null || args[i].intval != o.intval)
+ return Zero;
+ }
+ else
+ {
+ for (int i = 1; i < args.Length; i++)
+ if (o.objval.Equals (args[i].objval))
+ return Zero;
+ }
+ return One;
+ }
- for (int i = 1; i < args.Length; i++)
- n += (int) args[i].val;
- vari.val = n;
- return n;
- }
+ private static Term Fnoteq (Domain domain, Variable vari, Term[] args)
+ {
+ return Feq (domain, vari, args);
+ }
- private static object mul_set (Xex[] args, Domain domain)
- {
- Variable vari = domain.GetVar (args[0]);
- int n = (int) vari.val;
+ private static Term Flt (Domain domain, Variable vari, Term[] args)
+ {
+ int n = args[0].Intval;
- for (int i = 1; i < args.Length; i++)
- n *= (int) args[i].val;
- vari.val = n;
- return n;
- }
+ for (int i = 1; i < args.Length; i++)
+ {
+ int n1 = args[i].Intval;
+ if (n >= n1)
+ return Zero;
+ n = n1;
+ }
+ return One;
+ }
- private static object sub_set (Xex[] args, Domain domain)
- {
- Variable vari = domain.GetVar (args[0]);
- int n = (int) vari.val;
+ private static Term Fle (Domain domain, Variable vari, Term[] args)
+ {
+ int n = args[0].Intval;
+ for (int i = 1; i < args.Length; i++)
+ {
+ int n1 = args[i].Intval;
+ if (n > n1)
+ return Zero;
+ n = n1;
+ }
+ return One;
+ }
- for (int i = 1; i < args.Length; i++)
- n -= (int) args[i].val;
- vari.val = n;
- return n;
- }
+ private static Term Fgt (Domain domain, Variable vari, Term[] args)
+ {
+ int n = args[0].Intval;
+ for (int i = 1; i < args.Length; i++)
+ {
+ int n1 = args[i].Intval;
+ if (n <= n1)
+ return Zero;
+ n = n1;
+ }
+ return One;
+ }
- private static object div_set (Xex[] args, Domain domain)
- {
- Variable vari = domain.GetVar (args[0]);
- int n = (int) vari.val;
+ private static Term Fge (Domain domain, Variable vari, Term[] args)
+ {
+ int n = args[0].Intval;
+ for (int i = 1; i < args.Length; i++)
+ {
+ int n1 = args[i].Intval;
+ if (n < n1)
+ return Zero;
+ n = n1;
+ }
+ return One;
+ }
- for (int i = 1; i < args.Length; i++)
- n /= (int) args[i].val;
- vari.val = n;
- return n;
- }
+ private static Term Fappend (Domain domain, Variable vari, Term[] args)
+ {
+ List<Term> list;
- private static object mod_set (Xex[] args, Domain domain)
- {
- Variable vari = domain.GetVar (args[0]);
- int n = (int) vari.val;
+ if (vari == null)
+ list = new List<Term> ();
+ else
+ list = vari.val.Listval;
- for (int i = 1; i < args.Length; i++)
- n %= (int) args[i].val;
- vari.val = n;
- return n;
- }
+ foreach (Term arg in args)
+ {
+ if (arg.IsList)
+ list.AddRange ((List<Term>) arg.objval);
+ else
+ list.Add (arg);
+ }
+ if (vari == null)
+ {
+ Term result;
+ result.intval = 0;
+ result.objval = list;
+ return result;
+ }
+ return vari.val;
+ }
- private static object logior_set (Xex[] args, Domain domain)
- {
- Variable vari = domain.GetVar (args[0]);
- int n = (int) vari.val;
+ private static Term Fconcat (Domain domain, Variable vari, Term[] args)
+ {
+ string str;
- for (int i = 1; i < args.Length; i++)
- n |= (int) args[i].val;
- vari.val = n;
- return n;
- }
+ if (vari == null)
+ str = "";
+ else
+ str = vari.val.Strval;
- private static object logand_set (Xex[] args, Domain domain)
- {
- Variable vari = domain.GetVar (args[0]);
- int n = (int) vari.val;
+ foreach (Term arg in args)
+ {
+ if (arg.IsStr)
+ str += (string) arg.objval;
+ else if (arg.IsList)
+ foreach (Term term in (List<Term>) arg.objval)
+ str += (char) term.Intval;
+ else
+ str += (char) arg.Intval;
+ }
+ if (vari == null)
+ {
+ Term result;
+ result.intval = 0;
+ result.objval = str;
+ return result;
+ }
+ vari.val.objval = str;
+ return vari.val;
+ }
- for (int i = 1; i < args.Length; i++)
- n &= (int) args[i].val;
- vari.val = n;
- return n;
- }
+ private static Term Fnth (Domain domain, Variable vari, Term[] args)
+ {
+ Term result;
- private static object lsh (Xex[] args, Domain domain)
- {
- return (int) args[0].val << (int) args[1].val;
- }
+ if (args[1].IsStr)
+ {
+ result.intval = ((string) args[1].objval)[args[0].Intval];
+ result.objval = null;
+ }
+ else if (args[1].IsList)
+ {
+ result = ((List<Term>) args[1].objval)[args[0].Intval];
+ }
+ else
+ throw new Exception ("Term is not enumelable: " + args[1]);
+ return result;
+ }
- private static object lsh_set (Xex[] args, Domain domain)
- {
- Variable vari = domain.GetVar (args[0]);
- int n = (int) vari.val;
+ private static Term Fcopy (Domain domain, Variable vari, Term[] args)
+ {
+ Term result;
- n <<= (int) args[1].val;
- vari.val = n;
- return n;
- }
+ result.intval = 0;
+ result.objval = new List<Term> (args[0].Listval);
+ return result;
+ }
- private static object rsh (Xex[] args, Domain domain)
- {
- return (int) args[0].val >> (int) args[1].val;
- }
+ private static Term Fins (Domain domain, Variable vari, Term[] args)
+ {
+ if (vari.val.IsStr)
+ vari.val.objval
+ = vari.val.Strval.Insert (args[0].Intval, args[1].Strval);
+ else if (vari.val.IsList)
+ vari.val.Listval.InsertRange (args[0].Intval, args[1].Listval);
+ else
+ throw new Exception ("term is not collection: " + vari.val);
+ return vari.val;
+ }
- private static object rsh_set (Xex[] args, Domain domain)
- {
- Variable vari = domain.GetVar (args[0]);
- int n = (int) vari.val;
+ private static Term Fdel (Domain domain, Variable vari, Term[] args)
+ {
+ if (vari.val.IsStr)
+ vari.val.objval
+ = vari.val.Strval.Remove (args[0].Intval,
+ args[1].Intval - args[0].Intval);
+
+ else if (vari.val.IsList)
+ vari.val.Listval.RemoveRange (args[0].Intval,
+ args[1].Intval - args[0].Intval);
+ else
+ throw new Exception ("term is not collection: " + vari.val);
+ return vari.val;
+ }
- n >>= (int) args[1].val;
- vari.val = n;
- return n;
- }
+ private static Term Fand (Domain domain, Variable vari, Term[] args)
+ {
+ foreach (Term arg in args)
+ if (! arg.Eval (domain).IsTrue)
+ return Zero;
+ return One;
+ }
- private static object eq (Xex[] args, Domain domain)
- {
- int n = (int) args[0].val;
+ private static Term For (Domain domain, Variable vari, Term[] args)
+ {
+ foreach (Term arg in args)
+ if (arg.Eval (domain).IsTrue)
+ return One;
+ return Zero;
+ }
- for (int i = 1; i < args.Length; i++)
- if (n != (int) args[i].val)
- return false;
- return true;
- }
+ private static Term Feval (Domain domain, Variable vari, Term[] args)
+ {
+ return (args[0].Eval (domain));
+ }
- private static object noteq (Xex[] args, Domain domain)
- {
- return ((int) args[0].val != (int) args[1].val);
- }
+ private static Term Fprogn (Domain domain, Variable vari, Term[] args)
+ {
+ Term result = One;
- private static object less_than (Xex[] args, Domain domain)
- {
- int n = (int) args[0].val;
+ foreach (Term arg in args)
+ result = arg.Eval (domain);
+ return result;
+ }
- for (int i = 1; i < args.Length; i++)
- {
- int n1 = (int) args[i].val;
- if (n >= n1)
- return false;
- n = n1;
- }
- return true;
+ private static Term Fif (Domain domain, Variable vari, Term[] args)
+ {
+ if (args[0].Eval (domain).IsTrue)
+ return args[1].Eval (domain);
+ if (args.Length == 2)
+ return Zero;
+ return args[2].Eval (domain);
+ }
+
+ private static Term Fwhen (Domain domain, Variable vari, Term[] args)
+ {
+ if (! args[0].Eval (domain).IsTrue)
+ return Zero;
+ Term result = One;
+ for (int i = 1; i < args.Length; i++)
+ result = args[i].Eval (domain);
+ return result;
+ }
+
+ private static Term Freturn (Domain domain, Variable vari, Term[] args)
+ {
+ domain.ThrowReturn ();
+ return args.Length == 0 ? Zero : args[0];
+ }
+
+ private static Term Fbreak (Domain domain, Variable vari, Term[] args)
+ {
+ domain.ThrowBreak ();
+ return args.Length == 0 ? Zero : args[0];
+ }
+
+ private static Term Floop (Domain domain, Variable vari, Term[] args)
+ {
+ Term result = Zero;
+ try {
+ domain.Catch (CatchTag.Break);
+ while (! domain.Thrown)
+ foreach (Term arg in args)
+ {
+ result = arg.Eval (domain);
+ if (domain.Thrown)
+ return result;
+ }
+ } finally {
+ domain.Uncatch ();
}
+ return result;
+ }
- private static object less_eq (Xex[] args, Domain domain)
- {
- int n = (int) args[0].val;
- for (int i = 1; i < args.Length; i++)
- {
- int n1 = (int) args[i].val;
- if (n > n1)
- return false;
- n = n1;
- }
- return true;
+ private static Term Fwhile (Domain domain, Variable vari, Term[] args)
+ {
+ Term result = Zero;
+ try {
+ domain.Catch (CatchTag.Break);
+ while (! domain.Thrown && args[0].Eval (domain).IsTrue)
+ for (int i = 1; i < args.Length; i++)
+ {
+ result = args[i].Eval (domain);
+ if (domain.Thrown)
+ return result;
+ }
+ } finally {
+ domain.Uncatch ();
}
+ return result;
+ }
- private static object greater_than (Xex[] args, Domain domain)
- {
- int n = (int) args[0].val;
- for (int i = 1; i < args.Length; i++)
+ private static Term Fcond (Domain domain, Variable vari, Term[] args)
+ {
+ foreach (Term arg in args)
+ {
+ List<Term> list = arg.Listval;
+ Term result = list[0].Eval (domain);
+
+ if (result.IsTrue)
+ {
+ for (int i = 1; i < list.Count; i++)
+ result = list[i].Eval (domain);
+ return result;
+ }
+ }
+ return Zero;
+ }
+
+ private static Term Fforeach (Domain domain, Variable vari,
+ Term[] args)
+ {
+ Term result = args[0].Eval (domain);
+ if (domain.Thrown)
+ return result;
+ List<Term> list = result.Listval;
+ Bindings current = domain.bindings;
+
+ try {
+ domain.Catch (CatchTag.Break);
+ foreach (Term term in list)
{
- int n1 = (int) args[i].val;
- if (n <= n1)
- return false;
- n = n1;
+ domain.Bind (vari, term);
+ try {
+ for (int i = 1; i < args.Length; i++)
+ {
+ result = args[i].Eval (domain);
+ if (domain.Thrown)
+ return result;
+ }
+ } finally {
+ domain.UnboundTo (current);
+ }
}
- return true;
+ } finally {
+ domain.Uncatch ();
}
+ return result;
+ }
+
+ private static Term Fquote (Domain domain, Variable vari, Term[] args)
+ {
+ return new Term (args[0]);
+ }
+
+ private static Term Ftype (Domain domain, Variable vari, Term[] args)
+ {
+ if (args[0].IsInt)
+ return TermInt;
+ if (args[0].IsStr)
+ return TermStr;
+ if (args[0].IsSymbol)
+ return TermSymbol;
+ if (args[0].IsList)
+ return TermList;
+ return TermTerm;
+ }
+
+ public static Term Fcatch (Domain domain, Variable vari, Term[] args)
+ {
+ Term result = Zero;
+ try {
+ domain.Catch (new CatchTag (args[0].Symval));
+ result = args[1].Eval (domain);
+ } finally {
+ domain.Uncatch ();
+ }
+ return result;
+ }
+
+ public static Term Fthrow (Domain domain, Variable vari, Term[] args)
+ {
+ domain.ThrowTag (new CatchTag (args[0].Symval));
+ return (args.Length == 1 ? Zero : args[1]);
+ }
+
+ public delegate TermValue TermParser (Domain domain, XmlNode node);
+
+ public class TermType
+ {
+ public readonly Symbol type;
+ internal readonly TermParser parser;
- private static object greater_eq (Xex[] args, Domain domain)
+ public TermType (Symbol type, TermParser parser)
{
- int n = (int) args[0].val;
- for (int i = 1; i < args.Length; i++)
- {
- int n1 = (int) args[i].val;
- if (n < n1)
- return false;
- n = n1;
- }
- return true;
+ this.type = type;
+ this.parser = parser;
}
+ }
- private static object progn_clause (Xex[] args, Domain domain)
- {
- object result = true;
+ public abstract class TermValue
+ {
+ public virtual Term Eval (Domain domain) { return new Term (this); }
+ public abstract TermValue Clone ();
+ }
- foreach (Xex e in args)
- result = e.Eval (domain);
- return result;
- }
+ private class Funcall : TermValue
+ {
+ internal Function func;
+ internal Variable vari;
+ internal Term[] args;
- private static object if_clause (Xex[] args, Domain domain)
- {
- object result;
+ private Funcall (Function func, Variable vari, Term[] args)
+ {
+ this.func = func;
+ this.vari = vari;
+ this.args = args;
+ }
- if (is_true (args[0].Eval (domain)))
- result = args[1].Eval (domain);
- else
- {
- result = false;
- for (int i = 2; i < args.Length; i++)
- result = args[i].Eval (domain);
- }
- return result;
- }
+ public Funcall (Domain domain, Symbol fname, Term[] args)
+ {
+ func = domain.GetFunc (fname);
+ this.args = args;
+ }
- private static object when_clause (Xex[] args, Domain domain)
- {
- if (! is_true (args[0].Eval (domain)))
- return false;
+ public Funcall (Domain domain, Symbol fname, Symbol vname, Term[] args)
+ {
+ func = domain.GetFunc (fname);
+ int nargs = args.Length;
+ if (nargs < func.min_arg
+ || (func.max_arg >= 0 && nargs > func.max_arg))
+ throw new Exception ("Invalid number of arguments to: "
+ + fname + " " + nargs);
+ this.args = args;
+ if (vname != Qnull)
+ vari = domain.GetVar (vname, true);
+ }
- object result = true;
- for (int i = 1; i < args.Length; i++)
- result = args[i].Eval (domain);
+ internal static TermValue parser (Domain domain, XmlNode node)
+ {
+ Symbol fname = node.Name;
+ Symbol vname = Qnull;
+ XmlAttribute attr;
+
+ if (fname == Qfuncall)
+ fname = node.Attributes[Qfname].Value;
+ attr = node.Attributes[Qvname];
+ if (attr != null)
+ vname = attr.Value;
+
+ XmlNodeList nlist = node.ChildNodes;
+ int nargs = nlist.Count;
+ Term[] args = new Term[nargs];
+ for (int i = 0; i < nargs; i++)
+ args[i] = new Term (domain, nlist[i]);
+ return new Funcall (domain, fname, vname, args);
+ }
+
+ public override Term Eval (Domain domain)
+ {
+ domain.DebugWrite (true, "(({0}", func.name);
+ for (int i = 0; i < args.Length; i++)
+ domain.DebugWrite (false, " {0}", args[i].ToString ());
+ domain.DebugWrite (false, ")");
+ domain.depth++;
+ Term result = func.Call (domain, vari, args);
+ domain.depth--;
+ domain.DebugWrite (true, " ==> {0})", result.ToString ());
return result;
}
- private static object while_clause (Xex[] args, Domain domain)
+ public override TermValue Clone ()
{
- while (is_true (args[0].Eval (domain)))
- for (int i = 1; i < args.Length; i++)
- args[i].Eval (domain);
- return false;
+ return new Funcall (func, vari, args);
}
- // FUNCALL: function != null
- // VARREF: function == null, args[0] = DIRECT-SYMBOL
- // DIRECT: function == null, args == null
-
- private Function function;
- private Xex[] args;
- private object val;
+ public override string ToString ()
+ {
+ string str = "<funcall fname=\"" + func.name;
+ if (args == null)
+ return str + "\"/>";
+ str += "\">";
+ foreach (Term e in args)
+ str += e;
+ return (str + "</funcall>");
+ }
+ }
- public Xex[] Args { get { return args; } }
- public object Val { get { return val; } }
+ public struct Term
+ {
+ public int intval;
+ public object objval;
- private Xex () { }
+ public Term (int i) { intval = i; objval = null; }
+ public Term (Symbol name) { intval = 0; objval = name; }
+ public Term (string str) { intval = 0; objval = str; }
+ public Term (List<Term> list) { intval = 0; objval = list; }
+ public Term (Term term) { intval = term.intval; objval = term.objval; }
+ public Term (TermValue obj) { intval = 0; objval = obj; }
- private Xex (object val)
- {
- this.val = val;
- }
+ public Term (Domain domain, XmlNode node)
+ {
+ Symbol name = node.Name;
- private static Xex macro_expand (Xex[] bindings, Name[] args, Xex e)
- {
- Xex xex;
+ if (name == Qinteger)
+ {
+ intval = parse_integer (node.InnerText);
+ objval = null;
+ }
+ else
+ {
+ intval = 0;
+ if (name == Qsymbol)
+ objval = (Symbol) node.InnerText;
+ else if (name == Qstring)
+ objval = node.InnerText.Clone ();
+ else if (name == Qvarref)
+ objval = domain.GetVar ((Symbol) node.Attributes[0].Value, true);
+ else if (name == Qlist)
+ {
+ List<Term> list = new List<Term> ();
+ for (node = node.FirstChild; node != null;
+ node = node.NextSibling)
+ list.Add (new Term (domain, node));
+ objval = list;
+ }
+ else
+ {
+ TermType term_type;
+
+ if (domain.termtypes.TryGetValue (name, out term_type))
+ objval = term_type.parser (domain, node);
+ else
+ objval = Funcall.parser (domain, node);
+ }
+ }
+ }
- if (e.function != null)
+ public Term (Domain domain, Symbol vname)
{
- xex = new Xex ();
- xex.function = e.function;
- xex.args = new Xex[e.args.Length];
- for (int i = e.args.Length - 1; i >= 0; i--)
- xex.args[i] = macro_expand (bindings, args, e.args[i]);
+ intval = 0;
+ objval = domain.GetVar (vname, true);
}
- else if (e.args != null)
+
+ public Term (Domain domain, Symbol fname, Term[] args)
{
- xex = new Xex ();
- Name name = (Name) e.args[0].val;
- for (int i = args.Length - 1; i >= 0; i--)
- if (args[i] == name)
- return bindings[i];
- xex.function = null;
- xex.args = new Xex[1];
- xex.args[0] = e.args[0];
+ intval = 0;
+ objval = new Funcall (domain, fname, args);
}
- else
+
+ public Term (Domain domain, Symbol fname, Symbol vname, Term[] args)
{
- xex = e;
+ intval = 0;
+ objval = new Funcall (domain, fname, vname, args);
+ }
+
+ public object Objval {
+ get {
+ if (objval == null)
+ throw new Exception ("term is an integer: " + this);
+ return objval;
+ }
+ }
+
+ public int Intval {
+ get {
+ if (objval != null)
+ throw new Exception ("term is not integer: " + this);
+ return intval;
+ }
+ }
+
+ public string Strval {
+ get {
+ if (! IsStr)
+ throw new Exception ("term is not string: " + this);
+ return (string) objval;
+ }
+ }
+
+ public string Symval {
+ get {
+ if (! IsSymbol)
+ throw new Exception ("term is not symbol: " + this);
+ return (Symbol) objval;
+ }
+ }
+
+ public List<Term> Listval {
+ get {
+ if (! IsList)
+ throw new Exception ("term is not list: " + this);
+ return (List<Term>) objval;
+ }
+ }
+
+ public bool IsTrue {
+ get {
+ return (objval == null
+ ? (intval != 0)
+ : objval is List<Term>
+ ? (((List<Term>) objval).Count != 0)
+ : true);
}
- return xex;
+ }
+ public bool IsInt { get { return (objval == null); } }
+ public bool IsStr { get { return (objval is string); } }
+ public bool IsSymbol { get { return (objval is Symbol); } }
+ public bool IsList { get { return (objval is List<Term>); } }
+
+ public bool IsType (Type type)
+ {
+ return (objval == null ? type == typeof (int)
+ : type == objval.GetType ());
+ }
+
+ public Term Eval (Domain domain)
+ {
+ if (objval == null || objval is Symbol || objval is string)
+ return this;
+ if (objval is List<Term>)
+ return new Term ((List<Term>) objval);
+ return ((TermValue) objval).Eval (domain);
+ }
+
+ public Term Clone ()
+ {
+ if (objval == null || objval is Symbol || objval is string)
+ return this;
+ if (objval is List<Term>)
+ {
+ List<Term> list = new List<Term> ();
+ list.InsertRange (0, ((List<Term>) objval));
+ return new Term (list);
+ }
+ return new Term (((TermValue) objval).Clone ());
+ }
+
+ public override string ToString ()
+ {
+ string str;
+
+ if (objval == null)
+ str = "<integer>" + intval + "</integer>";
+ else if (objval is Symbol)
+ str = "<symbol>" + objval + "</symbol>";
+ else if (objval is string)
+ str = "<string>" + objval + "</string>";
+ else if (objval is List<Term>)
+ {
+ str = "<list>";
+ foreach (Term e in (List<Term>) objval)
+ str += e;
+ str += "</list>";
+ }
+ else if (objval is Funcall)
+ str = "<funcall fname=\"" + ((Funcall) objval).func.name + "\"/>";
+ else if (objval is Variable)
+ str = "<variable vname=\"" + ((Variable) objval).name + "\"/>";
+ else if (objval is Term)
+ str = "<quote>" + objval + "</quote>";
+ else
+ throw new Exception ("invalid Term object: " + objval);
+ return str;
+ }
}
+ static private Term Zero = new Term (0);
+ static private Term One = new Term (1);
+ static private Term TermInt = new Term (Qinteger);
+ static private Term TermStr = new Term (Qstring);
+ static private Term TermSymbol = new Term (Qsymbol);
+ static private Term TermList = new Term (Qlist);
+ static private Term TermTerm = new Term ((Symbol) "term");
+
internal static int parse_integer (string str)
{
int len = str.Length;
int c = str[0];
int i;
- if (c == '0' && str[1] == 'x')
+ if (c == '?')
+ return str[1];
+ if ((c == '0' || c == '#') && str[1] == 'x')
{
i = 0;
for (int idx = 2; idx < len; idx++)
return negative ? - i : i;
}
- private int pre_parse (XmlNodeList nlist, Domain domain)
- {
- int len = 0;
- foreach (XmlNode node in nlist)
- {
- if (node.Name == Ndefun)
- {
- XmlNode n = node.FirstChild;
- domain.Defun ((Name) node.Attributes[0].Value,
- n.Name == Nargs ? n.ChildNodes.Count : 0, false);
- }
- else if (node.Name == Ndefmacro)
- {
- XmlNode n = node.FirstChild;
- domain.Defun ((Name) node.Attributes[0].Value,
- n.Name == Nargs ? n.ChildNodes.Count : 0, true);
- }
- else if (node.Name == Ndefvar)
- {
- domain.Defvar ((Name) node.Attributes[0].Value, node.FirstChild);
- }
- else
- len++;
- }
- return len;
- }
+ private Term[] terms;
- private void post_parse (XmlNodeList nlist, Domain domain)
+ public static Term[] ParseTerms (Domain domain, XmlNode node)
{
- for (int i = 0, j = 0; i < nlist.Count; i++)
- {
- XmlNode node = nlist[i];
-
- if (node.Name == Ndefun)
- domain.Defun (node);
- else if (node.Name == Ndefmacro)
- domain.Defun (node);
- else if (node.Name != Ndefvar)
- args[j++] = new Xex (node, domain);
- }
+ int nterms = 0;
+ for (XmlNode n = node; n != null; n = n.NextSibling)
+ if (n.NodeType == XmlNodeType.Element)
+ {
+ if (n.Name == Qdefun)
+ domain.Defun (n, true);
+ else if (n.Name == Qdefvar)
+ domain.Defvar (n);
+ else
+ nterms++;
+ }
+ Term[] terms = new Term[nterms];
+ int i = 0;
+ for (XmlNode n = node; n != null; n = n.NextSibling)
+ if (n.NodeType == XmlNodeType.Element)
+ {
+ if (n.Name == Qdefun)
+ domain.Defun (n, false);
+ else if (n.Name != Qdefvar)
+ terms[i++]= new Term (domain, n);
+ }
+ return terms;
}
- private void Setup (XmlNode node, Domain domain)
+ public Xexpression (Domain domain, XmlNode node)
{
- Name name = node.Name;
-
- if (name == Nconst)
- {
- Name type = node.Attributes[Ntype].Value;
-
- if (type == Ninteger)
- val = parse_integer (node.InnerText);
- else if (type == Nstring)
- val = node.InnerText;
- else if (type == Nsymbol)
- val = (Name) node.InnerText;
- else if (type == Nboolean)
- val = node.InnerText == "true";
- else if (type == Nlist)
- {
- List<Xex> list = new List<Xex> ();
- for (XmlNode n = node.FirstChild; n != null; n = n.NextSibling)
- list.Add (new Xex (n, domain));
- val = list;
- }
- else
- throw new Exception ("Unknown type: " + type);
- }
- else if (name == Nvariable)
- {
- args = new Xex[1];
- args[0] = new Xex ((Name) node.Attributes[0].Value);
- }
- else
- {
- bool is_macro = false;
-
- if (name == Nfuncall)
- {
- name = node.Attributes[0].Value;
- if (Nmname == node.Attributes[0].Name)
- is_macro = true;
- }
-
- function = domain.GetFunc (name);
-
- XmlNodeList nlist = node.ChildNodes;
- int nargs = nlist.Count;
-
- if (nargs < function.min_arg
- || (function.max_arg >= 0 && nargs > function.max_arg))
- throw new Exception ("Invalid number of arguments to: "
- + name + " " + nargs);
- nargs = pre_parse (nlist, domain);
- args = new Xex[nargs];
- post_parse (nlist, domain);
-
- if (is_macro)
- {
- Function.Lambda lambda = function.lambda;
- Xex[] body = lambda.body;
- int len = body.Length;
- Xex[] newargs = new Xex[len];
-
- for (int i = 0; i < len; i++)
- newargs[i] = macro_expand (args, lambda.args, body[i]);
- function = Fprogn;
- args = newargs;
- }
- }
+ terms = ParseTerms (domain, node);
}
- public Xex (string url, Domain domain)
+ public Xexpression (Domain domain, string url)
{
- XmlDocument doc = new XmlDocument (Name.Table);
+ XmlDocument doc = new XmlDocument (Symbol.Table);
XmlNode node;
- using (XmlTextReader reader = new XmlTextReader (url, Name.Table))
+ using (XmlTextReader reader = new XmlTextReader (url, Symbol.Table))
{
do {
reader.Read ();
} while (reader.NodeType != XmlNodeType.None
&& (reader.NodeType != XmlNodeType.Element
- || Nexpr != reader.Name));
+ || reader.Name != Qexpr));
if (reader.NodeType == XmlNodeType.None)
throw new Exception ("Node <expr> not found");
node = doc.ReadNode (reader);
}
-
- Setup (node, domain);
+ terms = ParseTerms (domain, node.FirstChild);
}
-
- // EXPR = SYMBOL | MTEXT | INTEGER | FUNCALL | PROGN
- // FUNCALL = '(' SYMBOL EXPR* ')'
- // PROGN = '(' EXPR * ')'
- public Xex (XmlNode node, Domain domain)
+ public Term Eval (Domain domain)
{
- Setup (node, domain);
- }
+ Term result = Zero;
- public object Eval (Domain domain)
- {
- if (function == null)
- {
- if (args != null)
- {
- Variable vari = domain.GetVar ((Name) args[0].val);
- val = vari.val;
- }
- return val;
- }
- else
- val = function.Call (args, domain);
- return val;
+ domain.depth = 0;
+ try {
+ domain.Catch (CatchTag.Return);
+ foreach (Term term in terms)
+ {
+ result = term.Eval (domain);
+ if (domain.Thrown)
+ return result;
+ }
+ } finally {
+ domain.Uncatch ();
+ }
+ return result;
}
public override string ToString ()
{
- string str;
-
- if (function != null)
- {
- str = "(" + function.name;
- if (args != null)
- foreach (Xex e in args)
- str += " " + e.ToString ();
- str += ")";
- }
- else if (args != null)
- {
- str = (Name) args[0].val;
- }
- else if (val != null)
- {
- if (val is string)
- str = "\"" + ((string) val) + "\"";
- else
- str = val.ToString ();
- }
- else
- str = "()";
+ string str = "";
+ for (int i = 0; i < terms.Length; i++)
+ str += terms[i];
return str;
}
}