<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=""><br class=""><div><blockquote type="cite" class=""><div class="">On May 4, 2016, at 9:40 AM, Jordan Rose <<a href="mailto:jordan_rose@apple.com" class="">jordan_rose@apple.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div style="font-family: Helvetica; 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=""><blockquote type="cite" class=""><div class=""><br class="Apple-interchange-newline">On May 4, 2016, at 09:18, Joe Groff via swift-evolution <<a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><blockquote type="cite" class="" style="font-family: Helvetica; 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;"><br class="Apple-interchange-newline">On May 3, 2016, at 9:39 PM, Andrew Trick via swift-evolution <<a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a>> wrote:<br class=""><br class=""><br class=""><blockquote type="cite" class="">On May 3, 2016, at 8:56 PM, Chris Lattner <<a href="mailto:clattner@apple.com" class="">clattner@apple.com</a>> wrote:<br class=""><br class="">Hello Swift community,<br class=""><br class="">The review of "SE-0076: Add overrides taking an UnsafePointer source to non-destructive copying methods on UnsafeMutablePointer" begins now and runs through May 9. The proposal is available here:<br class=""><br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><a href="https://github.com/apple/swift-evolution/blob/master/proposals/0076-copying-to-unsafe-mutable-pointer-with-unsafe-pointer-source.md" class="">https://github.com/apple/swift-evolution/blob/master/proposals/0076-copying-to-unsafe-mutable-pointer-with-unsafe-pointer-source.md</a><br class=""><br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>* What is your evaluation of the proposal?<br class=""></blockquote><br class="">The new methods are needed, but they don’t need to be overloads. I have no idea why the argument type was originally declared Mutable.<br class=""><br class="">func assignBackwardFrom(source: UnsafePointer<Pointee>, count: Int<br class="">)<br class=""><br class="">func assignFrom(source: UnsafePointer<Pointee>, count: Int<br class="">)<br class=""><br class="">func initializeFrom(source: UnsafePointer<Pointee>, count: Int)<br class=""><br class="">FWIW: I made precisely this change a while back on an experimental branch while experimenting with UnsafePointer conversion. I don’t see a problem with it.<br class=""><br class="">Implicit argument conversion from UnsafeMutablePointer<Pointee> to UnsafePointer<Pointee> is normal and extremely obvious.<br class=""></blockquote><br class="" style="font-family: Helvetica; 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;"><span class="" style="font-family: Helvetica; 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; float: none; display: inline !important;">Yeah, Andy's approach seems cleaner than overloading.</span></div></blockquote><br class=""></div><div style="font-family: Helvetica; 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="">:-( …but it’s an implicit conversion. Which we’re trying to expunge from the language. (Sort of.)</div></div></blockquote><br class=""></div><div>I’ve heard exactly the opposite argument recently. Namely that explicit UnsafePointer construction indicates an “unsafe” cast (I personally don’t agree with that argument though).</div><div><br class=""></div><div>Tangential: Which of our current implicit conversions are considered bad? I can’t think of a good alternative, particularly for String/Array to UnsafePointer.</div><div><br class=""></div><div>-Andy</div><br class=""></body></html>