transf<R extends Object> method
Transforms the Outcome's generic type from T to R.
Uses the transformer function noFutures if provided, otherwise
attempts a direct cast.
Implementation
@override
@protected
@pragma('vm:prefer-inline')
Err<R> transf<R extends Object>([@noFutures R Function(T e)? noFutures]) {
return transfErr<R>();
}