mapOrNull<TResult extends Object?> method

  1. @optionalTypeArgs
TResult? mapOrNull<TResult extends Object?>({
  1. TResult? forceReply(
    1. ForceReply value
    )?,
  2. TResult? inlineKeyboard(
    1. InlineKeyboardMarkup value
    )?,
  3. TResult? keyboard(
    1. ReplyKeyboardMarkup value
    )?,
  4. TResult? keyboardRemove(
    1. ReplyKeyboardRemove 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(ForceReply value)? forceReply,
  TResult? Function(InlineKeyboardMarkup value)? inlineKeyboard,
  TResult? Function(ReplyKeyboardMarkup value)? keyboard,
  TResult? Function(ReplyKeyboardRemove value)? keyboardRemove,
}) {
  final _that = this;
  switch (_that) {
    case ForceReply() when forceReply != null:
      return forceReply(_that);
    case InlineKeyboardMarkup() when inlineKeyboard != null:
      return inlineKeyboard(_that);
    case ReplyKeyboardMarkup() when keyboard != null:
      return keyboard(_that);
    case ReplyKeyboardRemove() when keyboardRemove != null:
      return keyboardRemove(_that);
    case _:
      return null;
  }
}