whenOrNull<TResult extends Object?> method

  1. @optionalTypeArgs
TResult? whenOrNull<TResult extends Object?>({
  1. TResult? initial()?,
  2. TResult? unauthenticated()?,
  3. TResult? authenticated(
    1. User user
    )?,
})

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()?  initial,TResult? Function()?  unauthenticated,TResult? Function( User user)?  authenticated,}) {final _that = this;
switch (_that) {
case _Initial() when initial != null:
return initial();case _Unauthenticated() when unauthenticated != null:
return unauthenticated();case _Authenticated() when authenticated != null:
return authenticated(_that.user);case _:
  return null;

}
}