namespace System.Xml.Expression
{
- public abstract class Xex
+ public class Xexpression
{
+ public static int debug_level = 0;
+
public struct Name : IEquatable<Name>
{
private static NameTable nt = new NameTable ();
private static Name Nexpr = "expr";
private static Name Nfuncall = "funcall";
- private static Name Nvariable = "variable";
+ private static Name Nvarref = "varref";
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 Nfname = "fname";
private static Name Nargs = "args";
+ private static Name Nargs_unevalled = "args-unevalled";
+ private static Name Nfixed = "fixed";
private static Name Noptional = "optional";
private static Name Nrest = "rest";
- private static Name Nbody = "body";
private static Name Ndefvar = "defvar";
+ private static Name Nvname = "vname";
private static Name Ndescription = "description";
private static Name Nrange = "range";
private static Name Nprogn = "progn";
+ private static Name Nbreak = "break";
+ private static Name Nreturn = "return";
internal abstract class Function
{
- public readonly Name name;
+ public Name name;
public int min_arg, max_arg;
+ public Function () { }
+
public Function (Name name, int min_arg, int max_arg)
{
this.name = name;
this.max_arg = max_arg;
}
- public abstract object Call (Xex[] args, Domain domain);
+ public abstract Term Call (Domain domain, Variable vari, Term[] args);
public override string ToString ()
{
internal class Subroutine : Function
{
public Builtin builtin;
+ public bool setvar;
- public Subroutine (Builtin builtin, Name name,
+ public Subroutine (Builtin builtin, Name name, bool setvar,
int min_arg, int max_arg)
: base (name, min_arg, max_arg)
{
this.builtin = builtin;
}
- public override object Call (Xex[] args, Domain domain)
+ public override Term Call (Domain domain, Variable vari, Term[] args)
{
- object result;
-
- foreach (Xex a in args)
- if (a.Eval (domain) == null)
- throw new Exception (a + ":evaled to null");
- Console.Write ("calling (" + this);
- foreach (Xex a in args)
- Console.Write (" " + a);
- Console.Write (") => ");
- result = builtin (args, domain);
- Console.WriteLine (result);
- return result;
+ Term[] newargs = new Term[args.Length];
+
+ for (int i = 0; i < args.Length; i++)
+ {
+ newargs[i] = args[i].Eval (domain);
+ if (domain.Catched)
+ return newargs[i];
+ }
+ return builtin (domain, vari, newargs);
}
}
this.builtin = builtin;
}
- public override object Call (Xex[] args, Domain domain)
+ public override Term Call (Domain domain, Variable vari, Term[] args)
{
- object result;
-
- Console.Write ("calling (" + this);
- foreach (Xex a in args)
- Console.Write (" " + a);
- Console.Write (") => ");
- result = builtin (args, domain);
- Console.WriteLine (result);
- return result;
+ return builtin (domain, vari, args);
}
}
internal class Lambda : Function
{
- internal Xex[] args;
- internal Xex[] body;
-
- public Lambda (Name name, int min_arg, int max_arg)
- : base (name, min_arg, max_arg)
- {
- }
+ internal bool args_evalled;
+ internal Variable[] args;
+ internal Term[] body;
- public void SetArgs (XmlNode node, int nargs, Domain domain)
+ public Lambda (XmlNode node, Domain domain)
{
- args = new Xex[nargs];
+ int nfixed = 0;
+ int noptional = 0;
+ int nrest = 0;
+ name = node.Attributes[Nfname].Value;
+
node = node.FirstChild;
- for (int i = 0; i < nargs; node = node.NextSibling)
- if (node.Name != Noptional && node.Name != Nrest)
- args[i++] = New (node, domain);
+ if (node != null
+ && (node.Name == Nargs || node.Name == Nargs_unevalled))
+ {
+ XmlNode n;
+ args_evalled = node.Name == Nargs;
+ for (n = node.FirstChild; n != null; n = n.NextSibling)
+ {
+ if (n.Name == Nfixed)
+ nfixed++;
+ else if (n.Name == Noptional)
+ noptional++;
+ else if (n.Name == Nrest)
+ 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 ((Name) n.Attributes[0].Value);
+ if (nrest == 1)
+ max_arg = - max_arg;
+ }
+ else
+ {
+ min_arg = max_arg = 0;
+ }
}
public void SetBody (XmlNode node, Domain domain)
{
- XmlNodeList nlist = node.ChildNodes;
-
- body = new Xex[nlist.Count];
- for (int i = 0; i < nlist.Count; i++)
- body[i] = New (nlist[i], domain);
- }
-
- public void Setup (XmlNode node, Domain domain)
- {
- node = node.FirstChild;
- if (node.Name == Nargs)
+ for (node = node.FirstChild; node != null; node = node.NextSibling)
+ if (node.Name != Ndescription
+ && node.Name != Nargs
+ && node.Name != Nargs_unevalled)
+ break;
+ int nterms = 0;
+ for (XmlNode n = node; n != null; n = n.NextSibling)
+ nterms++;
+ if (nterms > 0)
{
- SetArgs (node, max_arg, domain);
- node = node.NextSibling;
+ body = new Term[nterms];
+ for (nterms = 0; node != null; node = node.NextSibling, nterms++)
+ body[nterms] = new Term (node, domain);
}
- if (node.Name == Nbody)
- SetBody (node, domain);
}
- public override object Call (Xex[] args, Domain domain)
+ public override Term Call (Domain domain, Variable vari, Term[] args)
{
Bindings current = domain.bindings;
- object result = false;
+ 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)
{
- Xex a = this.args[i];
- bool isdirect = a is Xex.Const;
- Name name = (isdirect
- ? (Name) a.val : ((Xex.Varref) a).vari.name);
- Variable var = domain.GetVar (name);
-
- if (isdirect)
- domain.Bind (var, args[i]);
- else
- domain.Bind (var, args[i].Eval (domain));
+ try {
+ domain.Catch (Nreturn);
+ foreach (Term term in body)
+ {
+ result = term.Eval (domain);
+ if (domain.Catched)
+ return result;
+ }
+ } finally {
+ domain.Uncatch ();
+ }
}
- Console.Write ("calling (" + this);
- foreach (Xex e in body)
- result = e.Eval (domain);
- Console.WriteLine (result);
} finally {
domain.UnboundTo (current);
}
return result;
}
-
- public override string ToString ()
- {
- string str = "(" + name;
- foreach (Xex a in args)
- str += " " + a;
- return (str + ")");
- }
}
}
- internal abstract class Variable
+ public abstract class Variable
{
public readonly Name name;
- public readonly Name type;
- internal object val;
+ internal Term val;
- public Variable (Name name, Name type, object value)
+ public Variable (Name name, Term term)
{
- if (value != null)
- Value = value;
this.name = name;
- this.type = type;
+ Value = term;
}
- public object Value
+ public Term Value
{
get { return val; }
set
{
if (! ValueP (value))
- throw new Exception ("Invalid value type: " + value);
+ throw new Exception ("Invalid value of " + name + ": " + value);
val = value;
}
}
- public abstract bool ValueP (object value);
+ public abstract bool ValueP (Term term);
- public override string ToString () { return name + "=" + val; }
- }
+ public override string ToString () { return name + "(" + val + ")"; }
- internal class VarInt : Variable
- {
- public struct Range
+ internal class Int : Variable
{
- public int from, to;
- }
+ public struct Range
+ {
+ public int from, to;
+ }
- public Range[] ranges;
+ public Range[] ranges;
- public VarInt (Name name, object value) : base (name, Ninteger, value) { }
+ public Int (Name name, int i) : base (name, new Term (i)) { }
- public override bool ValueP (object value)
- {
- int i;
+ public override bool ValueP (Term term)
+ {
+ 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)
+ if (term.objval != null)
+ return false;
+ if (ranges == null)
return true;
- return false;
+ i = term.intval;
+ foreach (Range r in ranges)
+ if (i >= r.from && i <= r.to)
+ return true;
+ return false;
+ }
}
- }
-
- internal class VarStr : Variable
- {
- public string[] ranges;
-
- public VarStr (Name name, object value) : base (name, Nstring, value) { }
- public override bool ValueP (object value)
+ internal class Str : Variable
{
- string str;
+ public string[] ranges;
- if (! (value is string))
- return false;
- if (ranges == null)
- return true;
- str = (string) value;
- foreach (string s in ranges)
- if (s == str)
- return true;
- return false;
- }
- }
-
- internal class VarBool : Variable
- {
- public VarBool (Name name, object value)
- : base (name, Nboolean, value) { }
+ public Str (Name name, string str) : base (name, new Term (str)) { }
- public override bool ValueP (object value)
- {
- if (! (value is bool))
+ public override bool ValueP (Term term)
+ {
+ if (! (term.objval is string))
+ return false;
+ if (ranges == null)
+ return true;
+ string str = (string) term.objval;
+ foreach (string s in ranges)
+ if (s == str)
+ return true;
return false;
- return true;
+ }
}
- }
- internal class VarMisc : Variable
- {
- public VarMisc (Name name, object value) : base (name, Nobject, value) { }
-
- public override bool ValueP (object value)
+ internal class Misc : Variable
{
- return true;
+ public Misc (Name name, Term term) : base (name, term) { }
+
+ public override bool ValueP (Term term) { return true; }
}
}
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 + ")";
}
}
public class Domain
{
public object context;
+ public int depth = 0;
internal Dictionary<Name, Function> functions;
internal Dictionary<Name, Variable> variables;
internal Bindings bindings;
+ private Stack<Name> catch_stack = new Stack<Name> ();
+ private int catch_count = -1;
internal Domain ()
{
this.context = context;
}
- internal void Bind (Variable vari, object value)
+ internal void Bind (Variable vari, Term value)
{
bindings = Bindings.Bind (bindings, vari, value);
- Console.WriteLine ("binding " + vari);
}
internal void UnboundTo (Bindings boundary)
bindings = bindings.UnboundTo (boundary);
}
- public void DefSubr (Builtin builtin, string str,
- int min_arg, int max_arg)
+ internal void Catch (Name name)
+ {
+ catch_stack.Push (name);
+ catch_count++;
+ Console.WriteLine ("catch {0}", catch_count);
+ }
+
+ internal bool Catched {
+ get {
+ Console.WriteLine ("catched {0} {1}",
+ catch_stack.Count,
+ catch_count);
+ return catch_stack.Count == catch_count; }
+ }
+
+ internal void ThrowReturn ()
+ {
+ Name tag = catch_stack.Peek ();
+ while (tag != Nreturn)
+ {
+ catch_stack.Pop ();
+ tag = catch_stack.Peek ();
+ }
+ catch_count = catch_stack.Count - 1;
+ }
+
+ internal void ThrowBreak ()
+ {
+ Name tag = catch_stack.Peek ();
+ if (tag != Nbreak)
+ throw new Exception ("No outer loop to break");
+ catch_count = catch_stack.Count - 1;
+ }
+
+ internal void Uncatch ()
+ {
+ catch_stack.Pop ();
+ catch_count = catch_stack.Count;
+ Console.WriteLine ("uncatch {0}", catch_count);
+ }
+
+ public void DefSubr (Builtin builtin, string str, bool setvar,
+ int min_arg, int max_arg, params string[] aliases)
{
Name name = str;
- functions[name]
- = new Function.Subroutine (builtin, name, min_arg, max_arg);
+ Function func = new Function.Subroutine (builtin, name, setvar,
+ min_arg, max_arg);
+ functions[name] = func;
+ foreach (string a in aliases)
+ functions[(Name) a] = func;
}
public void DefSpecial (Builtin builtin, string str,
- int min_arg, int max_arg)
+ int min_arg, int max_arg,
+ params string[] aliases)
{
Name name = str;
- functions[name]
- = new Function.SpecialForm (builtin, name, min_arg, max_arg);
+ Function func = new Function.SpecialForm (builtin, name,
+ min_arg, max_arg);
+ functions[name] = func;
+ foreach (string a in aliases)
+ functions[(Name) a] = func;
}
- private static Name ParseHead (XmlNode node,
- out int min_arg, out int max_arg)
+ public void DefAlias (string alias, string str)
{
- Name name = node.Attributes[Nfname].Value;
- int nargs = 0, noptions = 0, nrest = 0;
- XmlNode n;
-
- for (n = node.FirstChild; n != null; n = n.NextSibling)
- {
- if (n.Name == Noptional || n.Name == Nrest)
- break;
- nargs++;
- }
- if (n != null && n.Name == Noptional)
- for (n = n.NextSibling; n != null; n = n.NextSibling)
- {
- if (n.Name == Nrest)
- break;
- noptions++;
- }
- if (n != null && n.Name == Nrest)
- for (n = n.NextSibling; n != null; n = n.NextSibling)
- nrest++;
- min_arg = nargs;
- max_arg = nargs + noptions + nrest;
- if (nrest == 1)
- max_arg = - max_arg;
- return name;
+ functions[(Name) alias] = functions[(Name) str];
}
internal Function.Lambda RegisterFunction (XmlNode node)
{
- int min_arg, max_arg;
- Name name = ParseHead (node, out min_arg, out max_arg);
- Function.Lambda lambda = new Function.Lambda (name, min_arg, max_arg);
+ Function.Lambda lambda = new Function.Lambda (node, this);
- functions[name] = lambda;
+ functions[lambda.name] = lambda;
return lambda;
}
if (! functions.TryGetValue (name, out func))
func = RegisterFunction (node);
- ((Function.Lambda) func).Setup (node, this);
+ ((Function.Lambda) func).SetBody (node, this);
return func;
}
- public void Defvar (Name name, XmlNode node)
+ public void Defvar (XmlNode node)
{
+ Name name = node.Attributes[0].Value;
Variable vari;
+ node = node.FirstChild;
if (node.Name == Ndescription)
node = node.NextSibling;
if (node != null)
Name type = node.Name;
XmlNodeList range_list = null;
int nranges = 0;
+ string val = node.InnerText;
node = node.NextSibling;
if (node != null)
if (type == Ninteger)
{
- VarInt vi = new VarInt (name, parse_integer (val));
+ Variable.Int vi = new Variable.Int (name, parse_integer (val));
if (range_list != null)
{
- vi.ranges = new VarInt.Range[nranges];
+ vi.ranges = new Variable.Int.Range[nranges];
for (int i = 0; i < nranges; i++)
{
if (n.Name == Nrange)
{
vi.ranges[i].from =
- parse_integer (n.FirstChild.Value);
+ parse_integer (n.FirstChild.InnerText);
vi.ranges[i].to =
- parse_integer (n.LastChild.Value);
+ parse_integer (n.LastChild.InnerText);
}
else
{
- int num = parse_integer (n.Value);
+ int num = parse_integer (n.InnerText);
vi.ranges[i].from = vi.ranges[i].to = num;
}
}
}
else if (type == Nstring)
{
- VarStr vs = new VarStr (name, val);
+ Variable.Str vs = new Variable.Str (name, val);
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;
}
- else if (type == Nboolean)
- {
- vari = new VarBool (name, val == "true");
- }
else
throw new Exception ("Unknown type: " + type);
}
else
- vari = new VarMisc (name, null);
+ vari = new Variable.Misc (name, Zero);
variables[name] = vari;
}
+ internal Variable Defvar (Name name)
+ {
+ Variable vari = new Variable.Misc (name, Zero);
+ variables[name] = vari;
+ return vari;
+ }
+
internal Function GetFunc (Name name)
{
Function func;
Variable vari;
if (! variables.TryGetValue (name, out vari))
- variables[name] = vari = new VarMisc (name, null);
+ variables[name] = vari = new Variable.Misc (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";
str += ">";
return str;
}
+
+ 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 delegate object Builtin (Xex[] args, Domain domain);
+ public delegate Term Builtin (Domain domain, Variable vari, Term[] args);
private static Domain basic = new Domain ();
internal static Function Fprogn;
- static Xex ()
+ static Xexpression ()
{
- basic.DefSubr (set_value, "set", 2, 2);
- basic.DefSubr (set_value, "=", 2, 2);
- basic.DefSubr (and, "and", 1, -1);
- basic.DefSubr (and, "&&", 1, -1);
- basic.DefSubr (or, "or", 1, -1);
- basic.DefSubr (or, "||", 1, -1);
- basic.DefSubr (not, "not", 1, 1);
- basic.DefSubr (not, "!", 1, 1);
- basic.DefSubr (add, "add", 2, -1);
- basic.DefSubr (add, "+", 2, -1);
- basic.DefSubr (mul, "mul", 2, -1);
- basic.DefSubr (mul, "*", 2, -1);
- basic.DefSubr (sub, "sub", 1, -1);
- basic.DefSubr (sub, "-", 1, -1);
- basic.DefSubr (div, "div", 2, -1);
- basic.DefSubr (div, "/", 2, -1);
- basic.DefSubr (mod, "mod", 2, 2);
- basic.DefSubr (mod, "%", 2, 2);
- basic.DefSubr (logior, "logior", 2, -1);
- basic.DefSubr (logior, "|", 2, -1);
- basic.DefSubr (logand, "logand", 2, -1);
- basic.DefSubr (logand, "&", 2, -1);
- basic.DefSubr (add_set, "add-set", 2, -1);
- basic.DefSubr (add_set, "+=", 2, -1);
- basic.DefSubr (mul_set, "mul-set", 2, -1);
- basic.DefSubr (mul_set, "*=", 2, -1);
- basic.DefSubr (sub_set, "sub-set", 2, -1);
- basic.DefSubr (sub_set, "-=", 2, -1);
- basic.DefSubr (div_set, "div-set", 2, -1);
- basic.DefSubr (div_set, "/=", 2, -1);
- basic.DefSubr (mod_set, "mod-set", 2, 2);
- basic.DefSubr (mod_set, "%=", 2, 2);
- basic.DefSubr (logior_set, "logior-set", 2, -1);
- basic.DefSubr (logior_set, "|=", 2, -1);
- basic.DefSubr (logand_set, "logand-set", 2, -1);
- basic.DefSubr (logand_set, "&=", 2, -1);
- basic.DefSubr (lsh, "lsh", 2, 2);
- basic.DefSubr (lsh, "<<", 2, 2);
- basic.DefSubr (rsh, "rsh", 2, 2);
- basic.DefSubr (rsh, ">>", 2, 2);
- basic.DefSubr (lsh_set, "lsh-set", 2, 2);
- basic.DefSubr (lsh_set, "<<=", 2, 2);
- basic.DefSubr (rsh_set, "rsh-set", 2, 2);
- basic.DefSubr (rsh_set, ">>=", 2, 2);
- basic.DefSubr (eq, "eq", 2, -1);
- basic.DefSubr (eq, "==", 2, -1);
- basic.DefSubr (noteq, "noteq", 2, 2);
- basic.DefSubr (noteq, "!=", 2, 2);
- basic.DefSubr (less_than, "lt", 2, -1);
- basic.DefSubr (less_than, "<", 2, -1);
- basic.DefSubr (less_eq, "le", 2, -1);
- basic.DefSubr (less_eq, "<=", 2, -1);
- basic.DefSubr (greater_than, "gt", 2, -1);
- basic.DefSubr (greater_than, ">", 2, -1);
- basic.DefSubr (greater_eq, "ge", 2, -1);
- basic.DefSubr (greater_eq, ">=", 2, -1);
- basic.DefSubr (eval_clause, "eval", 1, 1);
- basic.DefSpecial (progn_clause, "progn", 0, -1);
- basic.DefSpecial (progn_clause, "expr", 0, -1);
- basic.DefSpecial (if_clause, "if", 2, -1);
+ basic.DefSubr (set_value, "set", true, 1, 1, "=");
+ basic.DefSubr (not, "not", false, 1, 1, "!");
+ basic.DefSubr (add, "add", true, 1, -1, "+");
+ basic.DefSubr (mul, "mul", true, 1, -1, "*");
+ basic.DefSubr (sub, "sub", true, 1, -1, "-");
+ basic.DefSubr (div, "div", true, 1, -1, "/");
+ basic.DefSubr (mod, "mod", true, 1, 2, "%");
+ basic.DefSubr (logior, "logior", true, 1, -1, "|");
+ basic.DefSubr (logand, "logand", true, 1, -1, "&");
+ basic.DefSubr (lsh, "lsh", true, 1, 2, "<<");
+ basic.DefSubr (rsh, "rsh", true, 1, 2, ">>");
+ basic.DefSubr (eq, "eq", false, 2, -1, "==");
+ basic.DefSubr (noteq, "noteq", false, 2, 2, "!=");
+ basic.DefSubr (less_than, "lt", false, 2, -1, "<");
+ basic.DefSubr (less_eq, "le", false, 2, -1, "<=");
+ basic.DefSubr (greater_than, "gt", false, 2, -1, ">");
+ basic.DefSubr (greater_eq, "ge", false, 2, -1, ">=");
+ basic.DefSubr (append, "append", true, 0, -1);
+ basic.DefSubr (concat, "concat", true, 0, -1);
+ basic.DefSubr (nth, "nth", false, 2, 2);
+ basic.DefSubr (copy, "copy", false, 1, 1);
+ basic.DefSubr (ins, "ins", true, 2, 2);
+ basic.DefSubr (del, "del", true, 2, 2);
+ basic.DefSubr (eval_clause, "eval", false, 1, 1);
+ basic.DefSubr (break_clause, "break", false, 0, 1);
+ basic.DefSubr (return_clause, "return", false, 1, 1);
+ basic.DefSpecial (and, "and", 1, -1, "&&");
+ basic.DefSpecial (or, "or", 1, -1, "||");
+ basic.DefSpecial (progn_clause, "progn", 0, -1, "expr");
+ basic.DefSpecial (if_clause, "if", 2, 3);
basic.DefSpecial (when_clause, "when", 1, -1);
+ basic.DefSpecial (loop_clause, "loop", 1, -1);
basic.DefSpecial (while_clause, "while", 1, -1);
+ basic.DefSpecial (cond_clause, "cond", 1, -1);
+ basic.DefSpecial (foreach_clause, "foreach", 2, -1);
+ basic.DefSpecial (quote_clause, "quote", 1, 1);
+ basic.DefSpecial (type_clause, "type", 1, 1);
Fprogn = basic.GetFunc (Nprogn);
}
- private static bool is_true (object val)
+ private static Term set_value (Domain domain, Variable vari, Term[] args)
{
- return (val is bool ? (bool) val
- : val is int ? (int) val == 0
- : true);
+ vari.Value = args[0];
+ return vari.val;
}
- private static object set_value (Xex[] args, Domain domain)
+ private static Term not (Domain domain, Variable vari, Term[] args)
{
- Variable vari = domain.GetVar (args[0]);
+ return args[0].IsTrue ? Zero : One;
+ }
- vari.Value = args[1].val;
+ private static Term add (Domain domain, Variable vari, Term[] args)
+ {
+ int n = vari == null ? 0 : vari.val.Intval;
+
+ foreach (Term arg in args)
+ n += (int) arg;
+ if (vari == null)
+ return n;
+ vari.val.intval = n;
return vari.val;
}
- private static object and (Xex[] args, Domain domain)
+ private static Term mul (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 *= (int) arg;
+ if (vari == null)
+ return n;
+ vari.val.intval = n;
+ return vari.val;
}
- private static object or (Xex[] args, Domain domain)
+ private static Term sub (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 -= (int) args[i++];
+ if (vari == null)
+ return n;
+ vari.val.intval = n;
+ return vari.val;
}
- private static object not (Xex[] args, Domain domain)
+ private static Term div (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 n;
+ vari.val.intval = n;
+ return vari.val;
}
- private static object add (Xex[] args, Domain domain)
+ private static Term mod (Domain domain, Variable vari, Term[] args)
{
- int n = 0;
- foreach (Xex e in args)
- n += (int) e.val;
- return n;
+ if (vari == null)
+ return (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)
+ private static Term logior (Domain domain, Variable vari, Term[] args)
{
- int n = 1;
- foreach (Xex e in args)
- n *= (int) e.val;
- return n;
+ int n = vari == null ? 0 : vari.val.Intval;
+ foreach (Term arg in args)
+ n |= (int) arg;
+ if (vari == null)
+ return n;
+ vari.val.intval = n;
+ return vari.val;
}
- private static object sub (Xex[] args, Domain domain)
+ private static Term logand (Domain domain, Variable vari, Term[] args)
{
- 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;
+ int n, i;
+
+ if (vari == null)
+ {
+ n = args[0].Intval;
+ i = 1;
+ }
+ else
+ {
+ n = vari.val.Intval;
+ i = 0;
+ }
+ while (i < args.Length)
+ n &= (int) args[i++];
+ if (vari == null)
+ return n;
+ vari.val.intval = n;
+ return vari.val;
}
- private static object div (Xex[] args, Domain domain)
+ private static Term lsh (Domain domain, Variable vari, Term[] args)
{
- int n = (int) args[0].val;
- for (int i = 1; i < args.Length; i++)
- n /= (int) args[i].val;
- return n;
+ if (vari == null)
+ return args[0].Intval << args[1].Intval;
+ vari.val.intval = vari.val.Intval << args[0].Intval;
+ return vari.val;
}
- private static object mod (Xex[] args, Domain domain)
+ private static Term rsh (Domain domain, Variable vari, Term[] args)
{
- return ((int) args[0].val % (int) args[1].val);
+ if (vari == null)
+ return 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)
+ private static Term eq (Domain domain, Variable vari, Term[] args)
{
- int n = 0;
- foreach (Xex e in args)
- n |= (int) e.val;
- return n;
+ Term o = args[0];
+
+ 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;
}
- private static object logand (Xex[] args, Domain domain)
+ private static Term noteq (Domain domain, Variable vari, Term[] args)
{
- int n = (int) args[0].val;
- for (int i = 1; i < args.Length; i++)
- n &= (int) args[i].val;
- return n;
+ return eq (domain, vari, args);
}
- private static object add_set (Xex[] args, Domain domain)
+ private static Term less_than (Domain domain, Variable vari, Term[] args)
{
- Variable vari = domain.GetVar (args[0]);
- int n = (int) vari.val;
+ int n = (int) args[0];
for (int i = 1; i < args.Length; i++)
- n += (int) args[i].val;
- vari.val = n;
- return n;
+ {
+ int n1 = (int) args[i];
+ if (n >= n1)
+ return Zero;
+ n = n1;
+ }
+ return One;
}
- private static object mul_set (Xex[] args, Domain domain)
+ private static Term less_eq (Domain domain, Variable vari, Term[] args)
{
- Variable vari = domain.GetVar (args[0]);
- int n = (int) vari.val;
-
+ int n = (int) args[0];
for (int i = 1; i < args.Length; i++)
- n *= (int) args[i].val;
- vari.val = n;
- return n;
+ {
+ int n1 = (int) args[i];
+ if (n > n1)
+ return Zero;
+ n = n1;
+ }
+ return One;
}
- private static object sub_set (Xex[] args, Domain domain)
+ private static Term greater_than (Domain domain, Variable vari, Term[] args)
{
- Variable vari = domain.GetVar (args[0]);
- int n = (int) vari.val;
-
+ int n = (int) args[0];
for (int i = 1; i < args.Length; i++)
- n -= (int) args[i].val;
- vari.val = n;
- return n;
+ {
+ int n1 = (int) args[i];
+ if (n <= n1)
+ return Zero;
+ n = n1;
+ }
+ return One;
}
- private static object div_set (Xex[] args, Domain domain)
+ private static Term greater_eq (Domain domain, Variable vari, Term[] args)
{
- Variable vari = domain.GetVar (args[0]);
- int n = (int) vari.val;
-
+ int n = (int) args[0];
for (int i = 1; i < args.Length; i++)
- n /= (int) args[i].val;
- vari.val = n;
- return n;
+ {
+ int n1 = (int) args[i];
+ if (n < n1)
+ return Zero;
+ n = n1;
+ }
+ return One;
}
- private static object mod_set (Xex[] args, Domain domain)
+ private static Term append (Domain domain, Variable vari, Term[] args)
{
- Variable vari = domain.GetVar (args[0]);
- int n = (int) vari.val;
+ List<Term> list;
- for (int i = 1; i < args.Length; i++)
- n %= (int) args[i].val;
- vari.val = n;
- return n;
+ if (vari == null)
+ list = new List<Term> ();
+ else
+ list = vari.val.Listval;
+
+ 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;
+ }
+ vari.val.objval = list;
+ return vari.val;
}
- private static object logior_set (Xex[] args, Domain domain)
+ private static Term concat (Domain domain, Variable vari, Term[] args)
{
- Variable vari = domain.GetVar (args[0]);
- int n = (int) vari.val;
+ 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;
+
+ 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;
}
- private static object logand_set (Xex[] args, Domain domain)
+ private static Term nth (Domain domain, Variable vari, Term[] args)
{
- Variable vari = domain.GetVar (args[0]);
- int n = (int) vari.val;
+ Term result;
- for (int i = 1; i < args.Length; i++)
- n &= (int) args[i].val;
- vari.val = n;
- return n;
+ 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 (Xex[] args, Domain domain)
+ private static Term copy (Domain domain, Variable vari, Term[] args)
{
- return (int) args[0].val << (int) args[1].val;
+ Term result;
+
+ result.intval = 0;
+ result.objval = new List<Term> (args[0].Listval);
+ return result;
}
- private static object lsh_set (Xex[] args, Domain domain)
+ private static Term ins (Domain domain, Variable vari, Term[] args)
{
- Variable vari = domain.GetVar (args[0]);
- int n = (int) vari.val;
-
- n <<= (int) args[1].val;
- vari.val = n;
- return n;
+ 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 (Xex[] args, Domain domain)
+ private static Term del (Domain domain, Variable vari, Term[] args)
{
- return (int) args[0].val >> (int) args[1].val;
+ 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;
}
- private static object rsh_set (Xex[] args, Domain domain)
+ private static Term and (Domain domain, Variable vari, Term[] args)
{
- Variable vari = domain.GetVar (args[0]);
- int n = (int) vari.val;
-
- n >>= (int) args[1].val;
- vari.val = n;
- return n;
+ foreach (Term arg in args)
+ if (! arg.Eval (domain).IsTrue)
+ return Zero;
+ return One;
}
- private static object eq (Xex[] args, Domain domain)
+ private static Term or (Domain domain, Variable vari, Term[] args)
{
- int n = (int) args[0].val;
-
- for (int i = 1; i < args.Length; i++)
- if (n != (int) args[i].val)
- return false;
- return true;
+ foreach (Term arg in args)
+ if (arg.Eval (domain).IsTrue)
+ return One;
+ return Zero;
}
- private static object noteq (Xex[] args, Domain domain)
+ private static Term eval_clause (Domain domain, Variable vari, Term[] args)
{
- return ((int) args[0].val != (int) args[1].val);
+ return (args[0].Eval (domain));
}
- private static object less_than (Xex[] args, Domain domain)
+ private static Term progn_clause (Domain domain, Variable vari, Term[] args)
{
- int n = (int) args[0].val;
+ Term result = One;
- for (int i = 1; i < args.Length; i++)
- {
- int n1 = (int) args[i].val;
- if (n >= n1)
- return false;
- n = n1;
- }
- return true;
+ foreach (Term arg in args)
+ result = arg.Eval (domain);
+ return result;
}
- private static object less_eq (Xex[] args, Domain domain)
+ private static Term if_clause (Domain domain, Variable vari, Term[] args)
{
- 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;
+ if (args[0].Eval (domain).IsTrue)
+ return args[1].Eval (domain);
+ if (args.Length == 2)
+ return Zero;
+ return args[2].Eval (domain);
}
- private static object greater_than (Xex[] args, Domain domain)
+ private static Term when_clause (Domain domain, Variable vari, Term[] args)
{
- int n = (int) args[0].val;
+ if (! args[0].Eval (domain).IsTrue)
+ return Zero;
+ Term result = One;
for (int i = 1; i < args.Length; i++)
- {
- int n1 = (int) args[i].val;
- if (n <= n1)
- return false;
- n = n1;
- }
- return true;
+ result = args[i].Eval (domain);
+ return result;
}
- private static object greater_eq (Xex[] args, Domain domain)
+ private static Term return_clause (Domain domain, Variable vari, Term[] args)
{
- 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;
- }
+ domain.ThrowReturn ();
+ return args.Length == 0 ? Zero : args[0];
+ }
- private static object eval_clause (Xex[] args, Domain domain)
+ private static Term break_clause (Domain domain, Variable vari, Term[] args)
{
- return ((Xex) args[0].val).Eval (domain);
- }
+ domain.ThrowBreak ();
+ return args.Length == 0 ? Zero : args[0];
+ }
- private static object progn_clause (Xex[] args, Domain domain)
+ private static Term loop_clause (Domain domain, Variable vari, Term[] args)
{
- object result = true;
-
- foreach (Xex e in args)
- result = e.Eval (domain);
+ Term result = Zero;
+ try {
+ domain.Catch (Nbreak);
+ while (! domain.Catched)
+ foreach (Term arg in args)
+ {
+ result = arg.Eval (domain);
+ if (domain.Catched)
+ break;
+ }
+ } finally {
+ domain.Uncatch ();
+ }
return result;
}
- private static object if_clause (Xex[] args, Domain domain)
+ private static Term while_clause (Domain domain, Variable vari, Term[] args)
{
- object result;
+ Term result = Zero;
+ try {
+ domain.Catch (Nbreak);
+ while (! domain.Catched && args[0].Eval (domain).IsTrue)
+ for (int i = 1; i < args.Length; i++)
+ {
+ result = args[i].Eval (domain);
+ if (domain.Catched)
+ break;
+ }
+ } finally {
+ domain.Uncatch ();
+ }
+ return result;
+ }
- if (is_true (args[0].Eval (domain)))
- result = args[1].Eval (domain);
- else
+ private static Term cond_clause (Domain domain, Variable vari, Term[] args)
+ {
+ foreach (Term arg in args)
{
- result = false;
- for (int i = 2; i < args.Length; i++)
- result = args[i].Eval (domain);
+ 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 result;
+ return Zero;
}
- private static object when_clause (Xex[] args, Domain domain)
+ private static Term foreach_clause (Domain domain, Variable vari,
+ Term[] args)
{
- if (! is_true (args[0].Eval (domain)))
- return false;
+ List<Term> list = args[0].Eval (domain).Listval;
+ Bindings current = domain.bindings;
+ Term result = Zero;
- object result = true;
- for (int i = 1; i < args.Length; i++)
- result = args[i].Eval (domain);
+ try {
+ domain.Catch (Nbreak);
+ foreach (Term term in list)
+ {
+ domain.Bind (vari, term);
+ try {
+ for (int i = 1; i < args.Length; i++)
+ {
+ result = args[i].Eval (domain);
+ if (domain.Catched)
+ break;
+ }
+ } finally {
+ domain.UnboundTo (current);
+ }
+ if (domain.Catched)
+ break;
+ }
+ } finally {
+ domain.Uncatch ();
+ }
return result;
}
- private static object while_clause (Xex[] args, Domain domain)
+ private static Term quote_clause (Domain domain, Variable vari, Term[] args)
{
- while (is_true (args[0].Eval (domain)))
- for (int i = 1; i < args.Length; i++)
- args[i].Eval (domain);
- return false;
+ return new Term (args[0]);
}
- // FUNCALL: function != null
- // VARREF: function == null, args[0] = DIRECT-SYMBOL
- // DIRECT: function == null, args == null
-
- private object val;
- public abstract object Eval (Domain domain);
- public object Val { get { return val; } }
+ private static Term type_clause (Domain domain, Variable vari, Term[] args)
+ {
+ if (args[0].IsInt)
+ return TermInt;
+ if (args[0].IsStr)
+ return TermStr;
+ if (args[0].IsName)
+ return TermName;
+ if (args[0].IsList)
+ return TermList;
+ return TermTerm;
+ }
- private class Funcall : Xex
+ public struct Term
{
- internal Function func;
- internal Xex[] args;
+ public int intval;
+ public object objval;
+
+ public Term (int i) { intval = i; objval = null; }
+ public Term (Name 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 = 0; objval = term; }
+
+ public Term (XmlNode node, Domain domain)
+ {
+ Name name = node.Name;
+
+ if (name == Ninteger)
+ {
+ intval = parse_integer (node.InnerText);
+ objval = null;
+ }
+ else
+ {
+ intval = 0;
+ if (name == Nsymbol)
+ objval = (Name) node.InnerText;
+ else if (name == Nstring)
+ objval = node.InnerText.Clone ();
+ else if (name == Nvarref)
+ objval = domain.GetVar ((Name) node.Attributes[0].Value);
+ else if (name == Nlist)
+ {
+ List<Term> list = new List<Term> ();
+ for (node = node.FirstChild; node != null;
+ node = node.NextSibling)
+ list.Add (new Term (node, domain));
+ objval = list;
+ }
+ else
+ {
+ Function func;
+ Variable vari = null;
+ Term[] args;
+
+ if (name == Nfuncall)
+ name = node.Attributes[0].Value;
+ else if (node.Attributes[Nvname] != null)
+ vari = domain.GetVar (node.Attributes[Nvname].Value);
+ func = domain.GetFunc (name);
+ XmlNodeList nlist = node.ChildNodes;
+ int nargs = nlist.Count;
+
+ if (nargs < func.min_arg
+ || (func.max_arg >= 0 && nargs > func.max_arg))
+ throw new Exception ("Invalid number of arguments to: "
+ + name + " " + nargs);
+ args = new Term[nargs];
+ for (int i = 0; i < nlist.Count; i++)
+ args[i] = new Term (nlist[i], domain);
+ objval = new Funcall (func, vari, args);
+ }
+ }
+ }
- public Funcall (Function func, Xex[] args)
+ private class Funcall
+ {
+ internal Function func;
+ internal Variable vari;
+ internal Term[] args;
+
+ public Funcall (Function func, Variable vari, Term[] args)
{
this.func = func;
+ this.vari = vari;
this.args = args;
}
- public override object Eval (Domain domain)
- {
- val = func.Call (args, domain);
- return val;
+ public 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;
+ }
+
+ 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 override string ToString ()
- {
- string str = "(" + func.name;
- if (args != null)
- foreach (Xex e in args)
- str += " " + e.ToString ();
- return (str + ")");
+ public int Intval {
+ get {
+ if (objval != null)
+ throw new Exception ("term is not integer: " + this);
+ return intval;
+ }
}
- }
- private class Varref : Xex
- {
- internal Variable vari;
+ public string Strval {
+ get {
+ if (! IsStr)
+ throw new Exception ("term is not string: " + this);
+ return (string) objval;
+ }
+ }
- public Varref (Variable vari)
- {
- this.vari = vari;
+ 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);
+ }
+ }
+ public bool IsInt { get { return (objval == null); } }
+ public bool IsStr { get { return (objval is string); } }
+ public bool IsName { get { return (objval is Name); } }
+ public bool IsList { get { return (objval is List<Term>); } }
- public override object Eval (Domain domain)
+ public Term Eval (Domain domain)
{
- val = vari.val;
- return val;
+ if (objval == null || objval is Name || objval is string)
+ return this;
+ if (objval is List<Term>)
+ return new Term ((List<Term>) objval);
+ if (objval is Funcall)
+ return ((Funcall) objval).Eval (domain);
+ if (objval is Variable)
+ return ((Variable) objval).val;
+ if (objval is Term)
+ return (Term) objval;
+ throw new Exception ("invalid Term object: " + objval);
}
- public override string ToString ()
+ public static explicit operator int (Term term)
{
- return "$" + vari.name + "/" + vari.val;
+ if (term.objval != null)
+ throw new Exception ("Not an integer term: " + term);
+ return term.intval;
}
- }
- private class Const : Xex
- {
- public Const (object val)
- {
- this.val = val;
- }
+ public static explicit operator Name (Term term)
+ {
+ return (Name) term.objval;
+ }
- public override object Eval (Domain domain)
+ public static implicit operator Term (int i)
{
- return val;
+ return new Term (i);
}
public override string ToString ()
{
- return val.ToString ();
+ string str;
+
+ if (objval == null)
+ str = "<integer>" + intval + "</integer>";
+ else if (objval is Name)
+ 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 Term Zero = new Term (0);
+ static Term One = new Term (1);
+ static Term TermInt = new Term (Ninteger);
+ static Term TermStr = new Term (Nstring);
+ static Term TermName = new Term (Nsymbol);
+ static Term TermList = new Term (Nlist);
+ static Term TermTerm = new Term ((Name) "term");
+
internal static int parse_integer (string str)
{
int len = str.Length;
return negative ? - i : i;
}
- private static int pre_parse (XmlNodeList nlist, Domain domain)
- {
- int len = 0;
- foreach (XmlNode node in nlist)
- {
- if (node.Name == Ndefun)
- domain.RegisterFunction (node);
- else if (node.Name == Ndefvar)
- domain.Defvar ((Name) node.Attributes[0].Value, node.FirstChild);
- else
- len++;
- }
- return len;
- }
-
- private static void post_parse (XmlNodeList nlist, Xex[] args,
- Domain domain)
- {
- for (int i = 0, j = 0; i < nlist.Count; i++)
- {
- XmlNode node = nlist[i];
+ private Term[] terms;
- if (node.Name == Ndefun)
- domain.Defun (node);
- else if (node.Name != Ndefvar)
- args[j++] = New (node, domain);
- }
- }
-
- public static Xex New (string url, Domain domain)
+ public Xexpression (string url, Domain domain)
{
XmlDocument doc = new XmlDocument (Name.Table);
XmlNode node;
reader.Read ();
} while (reader.NodeType != XmlNodeType.None
&& (reader.NodeType != XmlNodeType.Element
- || Nexpr != reader.Name));
+ || reader.Name != Nexpr));
if (reader.NodeType == XmlNodeType.None)
throw new Exception ("Node <expr> not found");
node = doc.ReadNode (reader);
}
- return New (node, domain);
+ int nterms = 0;
+ for (XmlNode n = node.FirstChild; n != null; n = n.NextSibling)
+ if (n.NodeType == XmlNodeType.Element)
+ {
+ if (n.Name == Ndefun)
+ domain.RegisterFunction (n);
+ else if (n.Name == Ndefvar)
+ domain.Defvar (n);
+ else
+ nterms++;
+ }
+
+ terms = new Term[nterms];
+ int i = 0;
+ for (XmlNode n = node.FirstChild; n != null; n = n.NextSibling)
+ if (n.NodeType == XmlNodeType.Element)
+ {
+ if (n.Name == Ndefun)
+ domain.Defun (n);
+ else if (n.Name != Ndefvar)
+ terms[i++]= new Term (n, domain);
+ }
}
- // EXPR = SYMBOL | MTEXT | INTEGER | FUNCALL | PROGN
- // FUNCALL = '(' SYMBOL EXPR* ')'
- // PROGN = '(' EXPR * ')'
- public static Xex New (XmlNode node, Domain domain)
+ public Term Eval (Domain domain)
{
- Name name = node.Name;
- Xex xex;
- if (name == Nvariable)
- {
- Variable vari = domain.GetVar ((Name) node.Attributes[0].Value);
- xex = new Xex.Varref (vari);
- }
- else if (name == Ninteger)
- xex = new Xex.Const (parse_integer (node.InnerText));
- else if (name == Nstring)
- xex = new Xex.Const (node.InnerText);
- else if (name == Nsymbol)
- xex = new Xex.Const ((Name) node.InnerText);
- else if (name == Nboolean)
- xex = new Xex.Const (node.InnerText == "true");
- else if (name == Nlist)
- {
- List<Xex> list = new List<Xex> ();
- for (XmlNode n = node.FirstChild; n != null; n = n.NextSibling)
- list.Add (New (n, domain));
- xex = new Xex.Const (list);
- }
- else
- {
- if (name == Nfuncall)
- name = node.Attributes[0].Value;
- Function func = domain.GetFunc (name);
-
- XmlNodeList nlist = node.ChildNodes;
- int nargs = nlist.Count;
-
- if (nargs < func.min_arg
- || (func.max_arg >= 0 && nargs > func.max_arg))
- throw new Exception ("Invalid number of arguments to: "
- + name + " " + nargs);
- nargs = pre_parse (nlist, domain);
- Xex[] args = new Xex[nargs];
- post_parse (nlist, args, domain);
- xex = new Xex.Funcall (func, args);
- }
- return xex;
+ Term result = Zero;
+
+ domain.depth = 0;
+ try {
+ domain.Catch (Nreturn);
+ foreach (Term term in terms)
+ {
+ result = term.Eval (domain);
+ if (domain.Catched)
+ break;
+ }
+ } finally {
+ domain.Uncatch ();
+ }
+ return result;
+ }
+
+ public override string ToString ()
+ {
+ string str = "";
+ for (int i = 0; i < terms.Length; i++)
+ str += terms[i];
+ return str;
}
}
}
projects / m17n / m17n-lib-cs.git / blobdiff