transformAsync method

Future<void> transformAsync(T f(T value), { _I batch = 1 << 16, })

transform, yielding to the event loop every batch elements so the UI stays live.

Checks the slice is still valid before each batch: an arena reset while this was waiting throws StateError here rather than letting it carry on writing into memory that now belongs to the next job.

Implementation

Future<void> transformAsync(
  T Function(T value) f, {
  _I batch = 1 << 16,
}) async {
  if (batch <= 0) throw RangeError.value(batch, 'batch');
  for (var c = 0; c < _chunks.length; c++) {
    var i = 0;
    while (true) {
      _check();
      final List<T> v = _views[c];
      if (i >= v.length) break;
      final _I end = i + batch < v.length ? i + batch : v.length;
      for (; i < end; i++) {
        v[i] = f(v[i]);
      }
      await Future<void>.delayed(.zero);
    }
  }
}