Method GetFacts

factstore/factstore.go:760–784

GetFacts implementation that looks up facts from an in-memory map.

(a ast.Atom, fn func(ast.Atom) error)

// GetFacts implementation that looks up facts from an in-memory map.
func (s *MultiIndexedArrayInMemoryStore) GetFacts(a ast.Atom, fn func(ast.Atom) error) error {
	if a.Predicate.Arity == 0 {
		if a, ok := s.constants[a.Predicate]; ok {
			return fn(a)
		}
		return nil
	}
	for i := 0; i < a.Predicate.Arity; i++ {
		// Find a non variable parameter.
		if _, ok := a.Args[i].(ast.Variable); !ok {
			h := a.Args[i].Hash()
			for _, facts := range s.shardsByPredicate[a.Predicate][uint16(i)][h] {
				for _, fact := range facts {
					if Matches(a.Args, fact.Args) {
						if err := fn(*fact); err != nil {
							return err
						}
					}
				}
			}
			return nil
		}
	}
	return s.getFactsOfFirstVariable(a, fn)
}

// Add implements the FactStore interface by adding the fact to the backing map.
func (s *MultiIndexedArrayInMemoryStore) Add(a ast.Atom) bool {