map<R> abstract method

Option<R> map<R>(
  1. R mapper(
    1. T value
    )
)

Maps a present value and leaves absent values unchanged.

final doubled = const Some<int>(2).map((value) => value * 2);
final missing = const None<int>().map((value) => value * 2);

Implementation

Option<R> map<R>(R Function(T value) mapper);