putAllAndUpdateExistingMapped<TMapped> abstract method

Future<void> putAllAndUpdateExistingMapped<TMapped>(
  1. Map<TKey, TMapped> newValues,
  2. TVal mutateExisting(
    1. TKey key,
    2. TVal? mutateMe,
    3. TMapped newValue
    )
)

Same as putAllAndUpdateExisting but mutateExisting can receive a null existing value

Implementation

Future<void> putAllAndUpdateExistingMapped<TMapped>(
  Map<TKey, TMapped> newValues,
  TVal Function(TKey key, TVal? mutateMe, TMapped newValue) mutateExisting,
);