Cumbersome to conditionally pass Value.absent()

[fgblomqvist]

If I have an optional parameter int? foo that I want to pass to a certain model field foo (let's say, an integer field with a default value), it gets quite wordy:

ThingCompanion.insert(
    ...
    foo: foo == null ? const Value.absent() : Value(startingBalance)
)

Is there a better way to do this? I feel like it's a quite common scenario.

[simolus3]

Thank you for starting this discussion. I've added Value.ofNullable which is similar, except that it checks that T is non-nullable as well:

Value<int>.ofNullable(null) -> absent
Value<int>.offNullable(12) -> present
Value<int?>.ofNullable(null) -> invalid (assertion error)! the null value could be both absent and present
Value<int?>.ofNullable(12) -> present

Until that is released, you can use your own function for that:

Value<T> valueOf<T>(T? value) {
  assert(value != null || null is! T);
  return value != null ? Value(value) : const Value<Never>.absent()`
}

[fgblomqvist]

Nice, looks good! Thanks 😄