updateT method

Map<K, V> updateT(
  1. K key,
  2. V update(
    1. V value
    ), {
  3. V ifAbsent()?,
  4. bool isUpdate = true,
})

update map 并返回 新map

Implementation

Map<K, V> updateT(K key, V Function(V value) update,
    {V Function()? ifAbsent, bool isUpdate = true}) {
  if (isUpdate) this.update(key, update, ifAbsent: ifAbsent);
  return this;
}