private IEnumerable <Stream> Query(Parser.Binding binding)
{
Relation relation = this.relations[binding.key];
Pair[] vars = TokenToPairs(binding.tokens);
Stream stream = new Stream();
foreach (Stream walkStream in relation.Query(vars).Walk(stream))
{
yield return(walkStream);
}
}
private void RemoveExclusions(Exclusion exclusion, Parser.Binding binding)
{
// Remove any claims that would conflict with the input claim (given by binding)
// via the given exclusion.
Relation relation = this.GetRelation(exclusion.relationKey);
Pair[] vars = new Pair[binding.tokens.Length];
for (int i = 0; i < vars.Length; i++)
{
if (exclusion.boundVars[i])
{
vars[i] = Pair.Value(binding.tokens[i].value);
}
else
{
vars[i] = Pair.Fresh();
}
}
if (!exclusion.rule.IsTrue(vars))
{
return;
}
List <string[]> varsToRemove = new List <string[]>();
foreach (Stream stream in relation.Query(vars, false).Walk(new Stream()))
{
string[] v = new string[vars.Length];
for (int i = 0; i < v.Length; i++)
{
v[i] = stream.Walk(vars[i]).key;
}
varsToRemove.Add(v);
}
foreach (string[] factToRemove in varsToRemove)
{
relation.RemoveFact(factToRemove);
}
}
public void AddCondition(Relation condition, Pair[] vars)
{
this.conditions.Add(condition.Query(this.SaltVars(vars)));
this.relations.Add(condition);
}