<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=""><div><blockquote type="cite" class=""><div class="">On Aug 8, 2017, at 3:24 PM, Daryle Walker via swift-evolution <<a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a>> wrote:</div><div class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class=""><blockquote type="cite" class=""><div class="">On Aug 8, 2017, at 12:35 AM, Félix Cloutier <<a href="mailto:felixcloutier@icloud.com" class="">felixcloutier@icloud.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><meta http-equiv="Content-Type" content="text/html charset=utf-8" class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class="">All this means is that `joined()` does not create an array that contains the new result. It's only as magic as the COW semantics on arrays.</div></div></div></blockquote><div class=""><br class=""></div><div class="">So you’re saying the COW semantics for Array and other standard library types have secret references/pointers that work even for “let”-mode objects, and the Sequence variants the various forms of “joined” need use a Sequence/Collection of those secret references?</div></div></div></div></blockquote><div><br class=""></div>Why would .joined() need some sort of special reference instead of just storing the collection values as normal values?</div><div><br class=""></div><div>John.</div><div><br class=""></div><div><br class=""><blockquote type="cite" class=""><div class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class=""><div class=""><br class=""></div><blockquote type="cite" class=""><div class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class=""><blockquote type="cite" class=""><div class="">Le 7 août 2017 à 21:12, Daryle Walker via swift-evolution <<a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a>> a écrit :</div><br class="Apple-interchange-newline"><div class=""><meta http-equiv="Content-Type" content="text/html charset=utf-8" class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class="">I was looking at random items at <a href="http://swiftdoc.org/" class="">SwiftDoc.org</a>, and noticed the “FlattenBidirectionalCollection” structure. It helps implement some versions of “joined” from Sequence (probably when the Sequence is also a BidirectionalCollection). The directions for the type state that “joined” does not create new storage. Then wouldn’t it have to refer to the source objects by reference? How; especially how does it work without requiring a “&” with “inout” or how it works with “let”-mode objects? Or am I misunderstanding how it works behind the covers?</div><div class=""><br class=""></div><div class="">(If there is a secret sauce to have one object refer to another without “&”/“inout”/“UnsafeWhateverPointer”, I like to know. It may help with implementing an idea. The idea involves extending the language, so “compiler magic” that the user can’t access is OK; I’d just claim to use the same sauce in my proposal.)</div></div></div></blockquote></div></div></div></blockquote></div><br class=""><div class=""><div class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class="">— </div><div class="">Daryle Walker<br class="">Mac, Internet, and Video Game Junkie<br class="">darylew AT mac DOT com </div></div></div><br class=""><div class=""><blockquote type="cite" class=""></blockquote></div></div></div>_______________________________________________<br class="">swift-evolution mailing list<br class=""><a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a><br class="">https://lists.swift.org/mailman/listinfo/swift-evolution<br class=""></div></blockquote></div><br class=""></body></html>