mapOrNull<TResult extends Object?> method

  1. @optionalTypeArgs
TResult? mapOrNull<TResult extends Object?>({
  1. TResult? initial(
    1. _Initial value
    )?,
  2. TResult? loading(
    1. _Loading value
    )?,
  3. TResult? success(
    1. _Success value
    )?,
  4. TResult? error(
    1. _Error 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( _Loading value)?  loading,TResult? Function( _Success value)?  success,TResult? Function( _Error value)?  error,}){
final _that = this;
switch (_that) {
case _Initial() when initial != null:
return initial(_that);case _Loading() when loading != null:
return loading(_that);case _Success() when success != null:
return success(_that);case _Error() when error != null:
return error(_that);case _:
  return null;

}
}