<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">Is there a bug tracking the remaining part of the implementation?<div class="">Shouldn’t the proposal still be under “Not yet implemented” as its not completely implemented?</div><div class=""><br class=""></div><div class="">David.<br class=""><div class=""><br class=""><div><blockquote type="cite" class=""><div class="">On 21 Jun 2016, at 22:22, Joe Groff <<a href="mailto:jgroff@apple.com" class="">jgroff@apple.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><blockquote type="cite" style="font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><br class="Apple-interchange-newline">On Jun 21, 2016, at 1:06 PM, David Hart via swift-evolution <<a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a>> wrote:<br class=""><br class="">Just saw this article about IUO in Swift 3.0:<br class=""><br class=""><a href="https://www.bignerdranch.com/blog/wwdc-2016-increased-safety-in-swift-3/" class="">https://www.bignerdranch.com/blog/wwdc-2016-increased-safety-in-swift-3/</a><br class=""><br class="">I was surprised that the IUO type still exists. From what I understood, SE-0054 gives a clear example that:<br class=""><br class="">func f() -> Int! { return 3 }<span class="Apple-converted-space"> </span><br class="">// f: () -> Int?, has IUO attribute<br class="">// ...<br class=""><br class="">let x3: Int! = f()<span class="Apple-converted-space"> </span><br class="">// succeeds; x3: Int? = .some(3), has IUO attribute<br class="">// ...<br class=""><br class="">func g() -> Int! { return nil }<span class="Apple-converted-space"> </span><br class="">// f: () -> Int?, has IUO attribute<br class="">// ...<br class=""><br class="">let y3: Int! = g() // succeeds; y3: Int? = .none, has IUO attribute<br class=""><br class="">x3 and y3 should be a of type Int? but trying those out in Xcode 8’s beta 1 playground show that they are still of type Int!. Did I miss something?<br class=""></blockquote><br style="font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><span style="font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;" class="">SE-0054 hasn't been fully implemented yet. The stricter implicit promotions are mostly there, but the IUO type still exists.</span><br style="font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><br style="font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><span style="font-family: Helvetica; font-size: 14px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;" class="">-Joe</span></div></blockquote></div><br class=""></div></div></body></html>