<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="">Sorry for the last email…I didn’t see your response.<div class=""><br class=""></div><div class="">I realize that disallowing IUOs in parameters (but not as properties) is inconsistent, but IUOs for properties make sense: they must be set during initialization, but sometimes this isn’t possible. IUOs make it possible to use the property just as any other non-Optional one, <b class="">provided the property is set before it is used</b> (see the proposal). This kind of guarantee doesn’t work for function parameters and return values. </div><div class=""><br class=""></div><div class="">As for IUOs for non-audited methods; why can’t they just all use Optional parameters? It should have the same behavior as before, since you can pass in both an Optional as well as a non-Optional even today.</div><div class=""><br class=""><div class="">
<div style="color: rgb(0, 0, 0); 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; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">Saagar Jha<br class=""><br class=""><br class=""></div>
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<br class=""><div><blockquote type="cite" class=""><div class="">On Jul 20, 2016, at 17:13, Chris Lattner <<a href="mailto:clattner@apple.com" class="">clattner@apple.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><blockquote type="cite" class="" style="font-family: SFUIText-Regular; font-size: 12px; 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-size-adjust: auto; -webkit-text-stroke-width: 0px;"><div class=""><br class="Apple-interchange-newline">On Jul 20, 2016, at 12:52 PM, Chris Lattner <<a href="mailto:clattner@apple.com" class="">clattner@apple.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="" style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">On Jul 19, 2016, at 3:46 PM, Saagar Jha <<a href="mailto:saagarjha28@gmail.com" class="">saagarjha28@gmail.com</a>> wrote:<br class=""><div class=""><blockquote type="cite" class=""><br class="Apple-interchange-newline"><div class=""><div class="" style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">I have updated the proposal <a href="https://gist.github.com/saagarjha/f33fecd4576f40133b6469da942ef453" class="">here</a>. Since this is a potentially a source breaking change, I’d like this to be considered for Swift 3; unless anyone has any issues with it, I’m going to push this to swift-evolution.</div></div></blockquote><div class=""><br class=""></div><div class="">Some comments:</div><div class="">- The syntax proposed would be *completely* unlike anything in Swift, and is semantically changing things unrelated to the type.</div><div class="">- This proposal doesn’t work, and overly punishes IUOs.</div><div class=""><br class=""></div><div class="">I recommend that we do not discuss this proposal, as it would not be a good use of community time. Beyond the unworkability of this specific proposal, in my personal opinion, there is nothing wrong with the T! syntax. Making it significantly more verbose would be a very *bad* thing for the intended use cases.</div></div></div></div></blockquote><div style="font-family: SFUIText-Regular; font-size: 12px; 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=""></div><div style="font-family: SFUIText-Regular; font-size: 12px; 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="">Hi Saagar,</div><div style="font-family: SFUIText-Regular; font-size: 12px; 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=""></div><div style="font-family: SFUIText-Regular; font-size: 12px; 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="">I’m sorry for the response above, I apparently misunderstood your early example to read it as putting the force unwrapping concept into the “forceUnwrapping” parameter label.</div><div style="font-family: SFUIText-Regular; font-size: 12px; 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=""></div><div style="font-family: SFUIText-Regular; font-size: 12px; 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="">I now see that your idea is to remove force unwrapping entirely for parameters. I am very concerned about this and think it would not be accepted into Swift. It makes the language less consistent (why can you do it on a property, but not a parameter) and eliminates important use cases for T!: overriding an non-nullability audited method.</div><div style="font-family: SFUIText-Regular; font-size: 12px; 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=""></div><div style="font-family: SFUIText-Regular; font-size: 12px; 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="">-Chris</div></div></blockquote></div><br class=""></div></body></html>