forEachEntryPrefix method

void forEachEntryPrefix(Uint8List prefix, void visit(Uint8List key, DocView? document))

Visits entries whose key starts with prefix, in key order.

Implementation

void forEachEntryPrefix(
  Uint8List prefix,
  void Function(Uint8List key, DocView? document) visit,
) {
  if (prefix.isEmpty) {
    forEachEntry(visit);
    return;
  }
  // Lower bound: first entry whose key is >= prefix.
  var low = 0;
  var high = _indexCount - 1;
  while (low <= high) {
    final middle = (low + high) >> 1;
    final comparison = _compareEntry(middle, prefix);
    if (comparison < 0) {
      low = middle + 1;
    } else {
      high = middle - 1;
    }
  }
  for (var i = low; i < _indexCount; i++) {
    final entryStart = _entryStart(i);
    final keyLength = VxsLe.u16(buffer, entryStart);
    if (keyLength < prefix.length ||
        !_rangeStartsWith(entryStart + 2, keyLength, prefix)) {
      break;
    }
    _visitEntry(i, visit);
  }
}