mapOrNull<TResult extends Object?> method

  1. @optionalTypeArgs
TResult? mapOrNull<TResult extends Object?>({
  1. TResult? preview(
    1. PaidMediaPreview value
    )?,
  2. TResult? photo(
    1. PaidMediaPhoto value
    )?,
  3. TResult? video(
    1. PaidMediaVideo value
    )?,
})

A variant of map that fallback to returning null.

It is equivalent to doing:

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

Implementation

@optionalTypeArgs
TResult? mapOrNull<TResult extends Object?>({
  TResult? Function(PaidMediaPreview value)? preview,
  TResult? Function(PaidMediaPhoto value)? photo,
  TResult? Function(PaidMediaVideo value)? video,
}) {
  final _that = this;
  switch (_that) {
    case PaidMediaPreview() when preview != null:
      return preview(_that);
    case PaidMediaPhoto() when photo != null:
      return photo(_that);
    case PaidMediaVideo() when video != null:
      return video(_that);
    case _:
      return null;
  }
}