whenOrNull<TResult extends Object?> method

  1. @optionalTypeArgs
TResult? whenOrNull<TResult extends Object?>({
  1. TResult? getKeys(
    1. String projectName,
    2. String boxName
    )?,
  2. TResult? getBoxList(
    1. String projectName
    )?,
  3. TResult? getValue(
    1. String projectName,
    2. String key,
    3. String boxName
    )?,
})

A variant of when that fallback to returning null

It is equivalent to doing:

switch (sealedClass) {
  case Subclass(:final field):
    return ...;
  case _:
    return null;
}

Implementation

@optionalTypeArgs
TResult? whenOrNull<TResult extends Object?>({
  TResult? Function(String projectName, String boxName)? getKeys,
  TResult? Function(String projectName)? getBoxList,
  TResult? Function(String projectName, String key, String boxName)? getValue,
}) {
  final _that = this;
  switch (_that) {
    case HiveGetKeys() when getKeys != null:
      return getKeys(_that.projectName, _that.boxName);
    case HiveGetBoxs() when getBoxList != null:
      return getBoxList(_that.projectName);
    case HiveGetValue() when getValue != null:
      return getValue(_that.projectName, _that.key, _that.boxName);
    case _:
      return null;
  }
}