mapOrNull<TResult extends Object?> method

  1. @optionalTypeArgs
TResult? mapOrNull<TResult extends Object?>({
  1. TResult? success(
    1. _Success value
    )?,
  2. TResult? failure(
    1. _Failure value
    )?,
  3. TResult? info(
    1. _Info value
    )?,
  4. TResult? warning(
    1. _Warning 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( _Success value)?  success,TResult? Function( _Failure value)?  failure,TResult? Function( _Info value)?  info,TResult? Function( _Warning value)?  warning,}){
final _that = this;
switch (_that) {
case _Success() when success != null:
return success(_that);case _Failure() when failure != null:
return failure(_that);case _Info() when info != null:
return info(_that);case _Warning() when warning != null:
return warning(_that);case _:
  return null;

}
}