mapOrNull<TResult extends Object?> method

@optionalTypeArgs TResult? mapOrNull<TResult extends Object?>({ TResult? text(InputTextMessageContent value)?, TResult? location(InputLocationMessageContent value)?, TResult? venue(InputVenueMessageContent value)?, TResult? contact(InputContactMessageContent value)?, TResult? invoice(InputInvoiceMessageContent 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(InputTextMessageContent value)? text,
  TResult? Function(InputLocationMessageContent value)? location,
  TResult? Function(InputVenueMessageContent value)? venue,
  TResult? Function(InputContactMessageContent value)? contact,
  TResult? Function(InputInvoiceMessageContent value)? invoice,
}) {
  final _that = this;
  switch (_that) {
    case InputTextMessageContent() when text != null:
      return text(_that);
    case InputLocationMessageContent() when location != null:
      return location(_that);
    case InputVenueMessageContent() when venue != null:
      return venue(_that);
    case InputContactMessageContent() when contact != null:
      return contact(_that);
    case InputInvoiceMessageContent() when invoice != null:
      return invoice(_that);
    case _:
      return null;
  }
}