mapOrNull<TResult extends Object?> method

  1. @optionalTypeArgs
TResult? mapOrNull<TResult extends Object?>({
  1. TResult? initial(
    1. _Initial value
    )?,
  2. TResult? unauthenticated(
    1. _Unauthenticated value
    )?,
  3. TResult? authenticated(
    1. _Authenticated 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( _Initial value)?  initial,TResult? Function( _Unauthenticated value)?  unauthenticated,TResult? Function( _Authenticated value)?  authenticated,}){
final _that = this;
switch (_that) {
case _Initial() when initial != null:
return initial(_that);case _Unauthenticated() when unauthenticated != null:
return unauthenticated(_that);case _Authenticated() when authenticated != null:
return authenticated(_that);case _:
  return null;

}
}