mapOrNull<TResult extends Object?> method

  1. @optionalTypeArgs
TResult? mapOrNull<TResult extends Object?>({
  1. TResult? server(
    1. ServerFailure value
    )?,
  2. TResult? cache(
    1. CacheFailure value
    )?,
  3. TResult? unexpected(
    1. UnexpectedFailure 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( ServerFailure value)?  server,TResult? Function( CacheFailure value)?  cache,TResult? Function( UnexpectedFailure value)?  unexpected,}){
final _that = this;
switch (_that) {
case ServerFailure() when server != null:
return server(_that);case CacheFailure() when cache != null:
return cache(_that);case UnexpectedFailure() when unexpected != null:
return unexpected(_that);case _:
  return null;

}
}