# SE-0268: Refine didSet Semantics **URL:** \ **Category:** Proposal Reviews\ **Created:** [October 21, 2019, 4:23pm UTC](https://forums.swift.org/t/se-0268-refine-didset-semantics/30049 "2019-10-21T16:23:38Z")\ **Posts on this page:** 1\ **Showing post:** 42
**Author:** ![ben-cohen](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/ben-cohen/32/296_2.png) [@ben-cohen](https://forums.swift.org/u/ben-cohen)\ **Post date:** [December 6, 2019, 12:18am UTC](https://forums.swift.org/t/se-0268-refine-didset-semantics/30049/42 "2019-12-06T00:18:54Z")
## Review #2 The core team discussed the review feedback, which was overall very positive, and believes in principle this is a good change to accept. During the review, some concern was expressed around how the mere use of `oldValue` in the body of the code would change the behavior. The core team suggested a slight amendment – that any code currently making use of an implicit `oldValue` receive a warning with a fixit adding it as an explicit argument. The new proposal is going out for a short re-review and that thread can be found [here](https://forums.swift.org/t/se-0268-review-2-review-didset-semantics/31396). --- _[View the full topic](https://forums.swift.org/t/se-0268-refine-didset-semantics/30049)._