private static InstantiationPath ExtendPathUpwardsWithInstantiations(InstantiationPath path, IEnumerable <Tuple <Quantifier, Term> > instantiations, Node node)
{
if (!instantiations.Any())
{
return(path);
}
var instantiation = instantiations.First();
var nodeInst = (Instantiation)node.UserData;
if (instantiation.Item1 != nodeInst.Quant || instantiation.Item2 != nodeInst.bindingInfo.fullPattern)
{
return(path);
}
var extendedPath = new InstantiationPath(path);
extendedPath.prepend(nodeInst);
var bestPath = extendedPath;
var remainingInstantiations = instantiations.Skip(1);
foreach (var predecessor in node.InEdges)
{
var candidatePath = ExtendPathUpwardsWithInstantiations(extendedPath, remainingInstantiations, predecessor.SourceNode);
if (candidatePath.Length() > bestPath.Length())
{
bestPath = candidatePath;
}
}
return(bestPath);
}
private static IEnumerable <InstantiationPath> AllUpPaths(InstantiationPath basePath, Node node, int nodesToGo)
{
if (nodesToGo <= 0 || !node.InEdges.Any())
{
return(Enumerable.Repeat(basePath, 1));
}
return(node.InEdges.SelectMany(e => {
var copy = new InstantiationPath(basePath);
copy.prepend((Instantiation)e.SourceNode.UserData);
return AllUpPaths(copy, e.SourceNode, nodesToGo - 1);
}));
}
