containsAll method
Returns a Set of dStringnt id of those documents that contain all the
keywords
.
Implementation
Set<String> containsAll(Iterable<String> keywords) {
final byTerm = getKeywordsPostings(keywords);
Set<String> intersection = byTerm.docIds;
for (final docPostings in byTerm.values) {
intersection = intersection.intersection(docPostings.keys.toSet());
}
return intersection;
}