public async Task ManyHouseCats()
{
var tom = Literal.NewAtom();
var heathcliff = Literal.NewAtom();
var sylvester = Literal.NewAtom();
var houseCat = Literal.NewFunctor(1);
var any = Literal.NewVariable();
var knowledge = KnowledgeBase.New()
.Assert(Clause.Always(houseCat.With(tom)))
.Assert(Clause.Always(houseCat.With(heathcliff)))
.Assert(Clause.Always(houseCat.With(sylvester)));
// Get all the cats
var solver = new SimpleDispatchingSolver();
await solver.LoadFromKnowledgeBase(knowledge);
var allResults = new List<ILiteral>();
for (var result = solver.Query(houseCat.With(any)); result != null && result.Success; result = await result.Next())
{
allResults.Add(result.Bindings.GetValueForVariable(any));
}
Assert.IsTrue(allResults.Contains(tom));
Assert.IsTrue(allResults.Contains(heathcliff));
Assert.IsTrue(allResults.Contains(sylvester));
Assert.AreEqual(3, allResults.Count);
}
public async Task SimpleChainQuery()
{
var knowledge = KnowledgeBase.New();
var houseCat = Literal.NewFunctor(1);
var feline = Literal.NewFunctor(1);
var small = Literal.NewFunctor(1);
var meows = Literal.NewFunctor(1);
var tom = Literal.NewAtom();
var jerry = Literal.NewAtom();
var X = Literal.NewVariable();
var Y = Literal.NewVariable();
// houseCat(X) :- small(X), feline(X)
var houseCatsAreSmallFelines = Clause.If(feline.With(X), small.With(X)).Then(houseCat.With(X));
var felinesMeow = Clause.If(meows.With(Y)).Then(feline.With(Y));
var tomIsSmall = Clause.Always(small.With(tom));
var jerryIsSmall = Clause.Always(small.With(jerry));
var tomMeows = Clause.Always(meows.With(tom));
knowledge = knowledge
.Assert(houseCatsAreSmallFelines)
.Assert(tomIsSmall)
.Assert(felinesMeow)
.Assert(jerryIsSmall)
.Assert(tomMeows);
var solver = new SimpleDispatchingSolver();
await solver.LoadFromKnowledgeBase(knowledge);
// Tom is a housecat
var result = solver.Query(houseCat.With(tom));
Assert.IsTrue(result.Success);
Assert.IsFalse((await result.Next()).Success);
// Jerry is not a housecat
result = solver.Query(houseCat.With(jerry));
Assert.IsFalse(result.Success);
}
public async Task MultiChainQuery()
{
var knowledge = KnowledgeBase.New();
var houseCat = Literal.NewFunctor(1);
var feline = Literal.NewFunctor(1);
var small = Literal.NewFunctor(1);
var meows = Literal.NewFunctor(1);
var tom = Literal.NewAtom();
var heathcliff = Literal.NewAtom();
var sylvester = Literal.NewAtom();
var X = Literal.NewVariable();
var Y = Literal.NewVariable();
// houseCat(X) :- small(X), feline(X)
var houseCatsAreSmallFelines = Clause.If(feline.With(X), small.With(X)).Then(houseCat.With(X));
var felinesMeow = Clause.If(meows.With(Y)).Then(feline.With(Y));
var tomIsSmall = Clause.Always(small.With(tom));
var heathcliffIsSmall = Clause.Always(small.With(heathcliff));
var sylvesterIsSmall = Clause.Always(small.With(sylvester));
var tomMeows = Clause.Always(meows.With(tom));
var heathcliffIsFeline = Clause.Always(feline.With(heathcliff));
var sylvesterMeows = Clause.Always(meows.With(sylvester));
knowledge = knowledge
.Assert(houseCatsAreSmallFelines)
.Assert(tomIsSmall)
.Assert(felinesMeow)
.Assert(tomMeows)
.Assert(heathcliffIsSmall)
.Assert(heathcliffIsFeline)
.Assert(sylvesterIsSmall)
.Assert(sylvesterMeows);
var solver = new SimpleDispatchingSolver();
await solver.LoadFromKnowledgeBase(knowledge);
// Get all the cats
var start = DateTime.Now;
for (var x = 0; x < 10000; ++x)
{
var allResults = new List<ILiteral>();
var any = Literal.NewVariable();
for (var result = solver.Query(houseCat.With(any)); result != null && result.Success; result = await result.Next())
{
allResults.Add(result.Bindings.GetValueForVariable(any));
}
Assert.IsTrue(allResults.Contains(tom));
Assert.IsTrue(allResults.Contains(heathcliff));
Assert.IsTrue(allResults.Contains(sylvester));
Assert.AreEqual(3, allResults.Count);
}
Console.WriteLine("10000 solutions in {0}s", (DateTime.Now - start).TotalSeconds);
}
/// <summary>
/// Creates a goal solver that works against the specified knowledge base
/// </summary>
public static async Task<ISolver> NewSolver(this IKnowledgeBase knowledge)
{
var result = new SimpleDispatchingSolver();
await result.LoadFromKnowledgeBase(knowledge);
return result;
}