private CheckerInfo PredicateCheckerInfo(PredicateInfo predicate)
{
CheckerInfo result;
if (checkerInfoTable.TryGetValue(predicate, out result))
return result;
return checkerInfoTable[predicate] = new CheckerInfo();
}
private void MarkDefined(PredicateInfo predicate, KnowledgeBaseRule rule)
{
CheckerInfo predicateCheckerInfo = PredicateCheckerInfo(predicate);
if (predicateCheckerInfo.DefiningRule == null)
{
predicateCheckerInfo.DefiningRule = rule;
}
}
internal PredicateInfo EntryForStoring(PredicateIndicator p)
{
PredicateInfo entry;
if (!db.TryGetValue(p, out entry))
{
db[p] = entry = new PredicateInfo(p.Functor, p.Arity, this);
}
return entry;
}
internal PredicateInfo CheckForPredicateInfo(PredicateIndicator p)
{
PredicateInfo info = CheckForPredicateInfoInThisKB(p);
if (info != null)
return info;
foreach (KnowledgeBase import in imports)
if ((info = import.CheckForPredicateInfo(p)) != null)
return info;
return null;
}
private CheckerInfo PredicateCheckerInfo(PredicateInfo predicate)
{
CheckerInfo result;
if (checkerInfoTable.TryGetValue(predicate, out result))
{
return(result);
}
return(checkerInfoTable[predicate] = new CheckerInfo());
}
internal ByteCompiledRule(PredicateInfo predicate, Structure head, Structure[] ruleBody, string source, int line)
: base(head, ruleBody, false, source, line)
{
this.predicate = predicate;
var c = new Compiler(head, ruleBody, KnowledgeBase);
code = c.Code;
frameSize = c.FrameSize;
Disassemble();
Console.WriteLine();
}
// ReSharper disable once InconsistentNaming
IEnumerable<CutState> ProveFromDB(Symbol functor, object[] args, PrologContext context)
{
PredicateInfo info = GetPredicateInfo(this, new PredicateIndicator(functor, args.Length));
if (info == null)
{
if (ErrorOnUndefined)
throw new UndefinedPredicateException(functor, args.Length);
return PrologPrimitives.FailImplementation;
}
return info.Prove(args, context);
}
private ushort StartCallInstruction(PrologContext context, int framePointer, ref ushort pc, out ushort succeedPC,
out IEnumerator <CutState> iterator)
{
int iteratorRegister = code[pc++];
ushort failPC = GetUShort(ref pc);
succeedPC = GetUShort(ref pc);
iterator = null;
// Make the iterator. How we do this depends on the opcode, so re-fetch it.
switch ((Opcode)code[pc - CallTargetOffset])
{
case Opcode.CallWokenGoals:
{
if (context.GoalsHaveWoken)
{
iterator = context.ProveAllWokenGoals().GetEnumerator();
}
}
break;
case Opcode.Call:
{
// It's a user-defined predicate call
PredicateInfo calledPredicate = GetPredicate(ref pc);
PushCallArgs(context, framePointer, predicate.Arity, ref pc);
iterator = calledPredicate.StackCall(context).GetEnumerator();
}
break;
case Opcode.CallPrimitive:
{
// It's a primitive call
PrologPrimitives.PrimitiveImplementation implementation = GetPrimitive(ref pc);
int arity = code[pc++];
PushCallArgs(context, framePointer, arity, ref pc);
iterator =
PrologPrimitives.StackCall(implementation, arity, context).GetEnumerator();
}
break;
default:
Debug.Assert(false, "Bad call opcode");
break;
}
context.SetStack(framePointer, iteratorRegister, iterator);
return(failPC);
}
internal PredicateInfo CheckForPredicateInfo(PredicateIndicator p)
{
PredicateInfo info = CheckForPredicateInfoInThisKB(p);
if (info != null)
{
return(info);
}
foreach (KnowledgeBase import in imports)
{
if ((info = import.CheckForPredicateInfo(p)) != null)
{
return(info);
}
}
return(null);
}
private static void SourceFromPredicateInfo(PredicateIndicator p, PredicateInfo predicateInfo, ISOPrologWriter writer)
{
foreach (var knowledgeBaseEntry in predicateInfo.Entries)
{
var rule = (KnowledgeBaseRule)knowledgeBaseEntry;
var head = new Structure(p.Functor, rule.HeadArgs);
Structure structure;
if (rule.BodyGoals == null || rule.BodyGoals.Length == 0)
{
structure = head;
}
else
{
structure = new Structure(Symbol.Implication, head, Commafy(rule.BodyGoals));
}
writer.Write(structure);
writer.WriteString(".\n");
}
}
void ReallyCheck()
{
WalkKB(KnowledgeBase.Global);
foreach (var component in UnityEngine.Object.FindObjectsOfType <KB>())
{
WalkKB(component.KnowledgeBase);
}
foreach (var pair in checkerInfoTable)
{
var checkerInfo = pair.Value;
if (!checkerInfo.Referenced)
{
KnowledgeBaseRule rule = checkerInfo.DefiningRule;
PredicateInfo global = KnowledgeBase.Global.CheckForPredicateInfo(new PredicateIndicator(rule.HeadFunctor, rule.HeadArity));
if (global == null || !global.External)
{
rule.PrintWarning("{0}/{1} is never used.", rule.HeadFunctor, rule.HeadArity);
}
}
}
}
private static void SourceFromPredicateInfo(PredicateIndicator p, PredicateInfo predicateInfo, ISOPrologWriter writer)
{
foreach (var knowledgeBaseEntry in predicateInfo.Entries)
{
var rule = (KnowledgeBaseRule)knowledgeBaseEntry;
var head = new Structure(p.Functor, rule.HeadArgs);
Structure structure;
if (rule.BodyGoals == null || rule.BodyGoals.Length == 0)
{
structure = head;
}
else
{
structure = new Structure(Symbol.Implication, head, Commafy(rule.BodyGoals));
}
writer.Write(structure);
writer.WriteString(".\n");
}
}
internal PredicateInfo EntryForStoring(PredicateIndicator p)
{
PredicateInfo entry;
if (!db.TryGetValue(p, out entry))
{
db[p] = entry = new PredicateInfo(p.Functor, p.Arity, this);
}
return entry;
}
private void MarkReferenced(PredicateInfo predicate)
{
PredicateCheckerInfo(predicate).Referenced = true;
}
private void MarkDefined(PredicateInfo predicate, KnowledgeBaseRule rule)
{
CheckerInfo predicateCheckerInfo = PredicateCheckerInfo(predicate);
if (predicateCheckerInfo.DefiningRule == null)
predicateCheckerInfo.DefiningRule = rule;
}
private void MarkReferenced(PredicateInfo predicate)
{
PredicateCheckerInfo(predicate).Referenced = true;
}
/// <summary>
/// Prints the byte code for the rule to System.Console.
/// </summary>
public void Disassemble()
{
ushort pc = 0;
while (pc < code.Length)
{
var opcode = (Opcode)code[pc++];
Console.Write("L{0}: {1} ", pc - 1, opcode.ToString());
switch (opcode)
{
case Opcode.MatchStructure:
{
Symbol functor = GetSymbol(ref pc);
int arity = code[pc++];
int endofMatch = GetUShort(ref pc);
Console.Write("{0}/{1}, L{2}, ", functor.Name, arity, endofMatch);
DisassembleOperand(ref pc);
}
break;
case Opcode.MatchVar:
case Opcode.MatchVarFirst:
{
if (opcode == Opcode.MatchVarFirst)
{
Console.Write("{0}, ", GetSymbol(ref pc));
}
byte register = code[pc++];
Console.Write("{0}, ", FormatRegister(register));
DisassembleOperand(ref pc);
}
break;
case Opcode.MatchLiteral:
{
Console.Write(GetLiteral(ref pc));
Console.Write(", ");
DisassembleOperand(ref pc);
}
break;
case Opcode.BuildStructure:
{
Console.Write(GetSymbol(ref pc));
Console.Write("/{0}, ", code[pc++]);
DisassembleOperand(ref pc);
}
break;
case Opcode.BuildVar:
{
Console.Write(GetSymbol(ref pc));
Console.Write(", ");
DisassembleOperand(ref pc);
}
break;
case Opcode.BuildReg:
{
byte reg = code[pc++];
Console.Write("{0}, ", FormatRegister(reg));
DisassembleOperand(ref pc);
}
break;
case Opcode.BuildLiteral:
{
Console.Write(GetLiteral(ref pc));
DisassembleOperand(ref pc);
}
break;
case Opcode.Call:
case Opcode.CallPrimitive:
case Opcode.CallWokenGoals:
{
Console.Write("{0}", FormatRegister(code[pc++]));
Console.Write(", {0}", FormatLabel(GetUShort(ref pc)));
Console.Write(", {0}", FormatLabel(GetUShort(ref pc)));
if (opcode != Opcode.CallWokenGoals)
{
int arity;
if (opcode == Opcode.Call)
{
PredicateInfo p = GetPredicate(ref pc);
Console.Write(", {0}/{1}", p.Name, p.Arity);
arity = p.Arity;
}
else
{
PrologPrimitives.PrimitiveImplementation impl = GetPrimitive(ref pc);
arity = code[pc++];
Console.Write(", {0}/{1}", PrologPrimitives.PrimitiveName(impl), arity);
}
while (arity-- > 0)
{
Console.Write(", ");
int arg = code[pc++];
if (arg < 0x80)
{
Console.Write("{0}", FormatRegister(arg)); // It's a register
}
else
{
// It's a literal
arg = ((arg & 0x7f) << 8) + code[pc++];
Console.Write(GlobalLiteralTable[arg]);
}
}
}
}
break;
default:
throw new Exception("Unknown opcode " + opcode);
}
Console.WriteLine();
}
}
internal IEnumerable <CutState> FindClauses(Structure head, object body)
{
PredicateInfo i = CheckForPredicateInfo(head.PredicateIndicator);
return((i == null)?CutStateSequencer.Fail():i.FindClauses(head, body));
}
private PredicateInfo GetPredicate(ref ushort pc)
{
PredicateInfo pred = PredicateTable[GetUShort(ref pc)];
return(pred);
}
/// <summary>
/// Add a term (fact or rule) to the KB.
/// </summary>
public void Assert(Structure structure, bool atEnd, bool checkSingletons)
{
if (structure == null)
{
throw new ArgumentNullException("structure", "Term to add to KB may not be null.");
}
//structure = structure.Expand();
if (structure == null)
{
throw new ArgumentNullException("structure");
}
Structure head = structure.IsFunctor(Symbol.Implication, 2)
? Term.Structurify(structure.Argument(0),
"Head of :- must be a valid proposition or predicate.")
: structure;
if (head.IsFunctor(Symbol.ColonColon, 2))
{
var argument = head.Argument(0);
var kb = argument as KnowledgeBase;
if (kb == null)
{
var o = argument as GameObject;
if (o != null)
{
kb = o.KnowledgeBase();
}
else
{
var c = argument as Component;
if (c != null)
{
kb = c.KnowledgeBase();
}
else
{
throw new ArgumentTypeException(
"assert",
"knowledgebase",
argument,
typeof(KnowledgeBase));
}
}
}
if (structure.IsFunctor(Symbol.Implication, 2))
{
kb.Assert(
new Structure(Symbol.Implication, head.Argument(1), structure.Argument(1)),
atEnd,
checkSingletons);
}
else
{
kb.Assert(structure.Argument(1), atEnd, checkSingletons);
}
}
else
{
if (PrologPrimitives.Implementations.ContainsKey(head.Functor))
{
throw new PrologException(
new Structure(
"error",
new Structure(
"permission_error",
Symbol.Intern("modify"),
Symbol.Intern("static_procedure"),
Term.PredicateIndicatorExpression(head))));
}
KnowledgeBaseRule assertion = KnowledgeBaseRule.FromTerm(
structure,
checkSingletons,
Prolog.CurrentSourceFile,
Prolog.CurrentSourceLineNumber);
PredicateInfo info = EntryForStoring(head.PredicateIndicator);
PredicateInfo parentInfo;
if (!info.Shadow && this.Parent != null &&
(parentInfo = this.Parent.CheckForPredicateInfoInThisKB(head.PredicateIndicator)) != null &&
!parentInfo.External)
{
throw new PrologException(
new Structure(
"error",
new Structure(
"permission_error",
Symbol.Intern("shadow"),
Term.PredicateIndicatorExpression(head))));
}
info.Assert(assertion, atEnd);
}
}