/// <summary>
/// Gets the locators of this locators subterms
/// </summary>
public override Locator this[int index]
{
get
{
Contract.Assert(index >= 0 && index < Arity);
bool gotLock = false;
try
{
argsLock.Enter(ref gotLock);
if (args != null)
{
return(args[index]);
}
args = new NodeTermLocator[locatorTerm.Symbol.Arity];
FuncTerm ftnode;
if (locatorNode.NodeKind == NodeKind.FuncTerm &&
(ftnode = (FuncTerm)locatorNode).Args.Count == locatorTerm.Symbol.Arity)
{
int i = 0;
foreach (var a in ftnode.Args)
{
args[i] = new NodeTermLocator(a, locatorTerm.Args[i]);
++i;
}
}
else
{
for (int i = 0; i < locatorTerm.Args.Length; ++i)
{
args[i] = new NodeTermLocator(locatorNode, locatorTerm.Args[i]);
}
}
return(args[index]);
}
finally
{
if (gotLock)
{
argsLock.Exit();
}
}
}
}
/// <summary>
/// Computes a set of locators
/// </summary>
/// <returns></returns>
public LinkedList <Locator> ComputeLocators()
{
if (CoreRule == null)
{
//// Then this is a fact.
ModelFactLocator loc;
var locs = new LinkedList <Locator>();
//// Not implemented for renamed fact sets. Return some locator associated with some fact set.
if (factSets.Count > 1 ||
!factSets.ContainsKey(string.Empty) ||
!factSets[string.Empty].TryGetLocator(Conclusion, out loc))
{
using (var it = factSets.GetEnumerator())
{
it.MoveNext();
locs.AddLast(new NodeTermLocator(
it.Current.Value.Model.Node,
Conclusion));
}
}
else
{
locs.AddLast(loc);
}
return(locs);
}
else if (premises.Count == 0)
{
var locs = new LinkedList <Locator>();
locs.AddLast(new NodeTermLocator(
CoreRule.Node,
Conclusion));
return(locs);
}
else
{
Contract.Assert(CoreRule.Kind == CoreRule.RuleKind.Regular);
FactSet sourceFacts;
if (factSets.TryFindValue(string.Empty, out sourceFacts) && sourceFacts.Rules.IsSubRuleCopy(CoreRule))
{
Contract.Assert(premises.Count == 1);
var inputProof = premises.First().Value.Item2;
return(MkSubRuleLocators(
CoreRule.Node,
inputProof.Conclusion,
Conclusion,
inputProof.ComputeLocators()));
}
//// Terms in the body for which locations are known.
var bodyTerm2Locs = new Map <Term, LinkedList <Locator> >(Term.Compare);
//// The bindings of body variables implied by the binding variable and its pattern.
var bodyVar2Bindings = new Map <Term, Term>(Term.Compare);
//// Records to the set of variable bindings in this pass.
var newVarBindings = new Stack <Term>();
foreach (var kv in premises)
{
MkBodyLocators(
kv.Value.Item2.ComputeLocators(),
kv.Value.Item2.Conclusion,
kv.Key,
kv.Value.Item1,
bodyTerm2Locs,
bodyVar2Bindings,
newVarBindings);
}
if (CoreRule.AdditionalVarDefs != null)
{
Set <Term> eqs;
while (newVarBindings.Count > 0)
{
var x = newVarBindings.Pop();
if (!CoreRule.AdditionalVarDefs.TryFindValue(x, out eqs) || eqs.Count == 0)
{
continue;
}
var xlocs = bodyTerm2Locs[x];
var xbinding = bodyVar2Bindings[x];
foreach (var eq in eqs)
{
MkBodyLocators(
xlocs,
xbinding,
x,
eq,
bodyTerm2Locs,
bodyVar2Bindings,
newVarBindings);
}
}
}
//// The bindings of variables or variable selectors implied by the conclusion and the head.
//// A variable in the head may have multiple bindings due to renamings.
var head2Bindings = new Map <Term, Set <Term> >(Term.Compare);
MkHeadBindings(Conclusion, CoreRule.Head, head2Bindings, bodyTerm2Locs, bodyVar2Bindings);
return(MkRuleLocators(
NodeTermLocator.ChooseRepresentativeNode(CoreRule.Node, Conclusion),
CoreRule.Head,
head2Bindings,
bodyTerm2Locs));
}
}
