in lib/src/boollist.dart [133:160]
void fillRange(int start, int end, [bool? fill]) {
RangeError.checkValidRange(start, end, _length);
fill ??= false;
var startWord = start >> _entryShift;
var endWord = (end - 1) >> _entryShift;
var startBit = start & _entrySignBitIndex;
var endBit = (end - 1) & _entrySignBitIndex;
if (startWord < endWord) {
if (fill) {
_data[startWord] |= -1 << startBit;
_data.fillRange(startWord + 1, endWord, -1);
_data[endWord] |= (1 << (endBit + 1)) - 1;
} else {
_data[startWord] &= (1 << startBit) - 1;
_data.fillRange(startWord + 1, endWord, 0);
_data[endWord] &= -1 << (endBit + 1);
}
} else {
if (fill) {
_data[startWord] |= ((1 << (endBit - startBit + 1)) - 1) << startBit;
} else {
_data[startWord] &= ((1 << startBit) - 1) | (-1 << (endBit + 1));
}
}
}