<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="">None of those are affected. See the note in the proposal.<div class=""><br class=""></div><div class="">~Robert Widmann</div><div class=""><br class=""><div><blockquote type="cite" class=""><div class="">On May 5, 2017, at 1:16 AM, Adrian Zubarev <<a href="mailto:adrian.zubarev@devandartist.com" class="">adrian.zubarev@devandartist.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="bloop_markdown" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(254, 254, 254);"><p style="margin: 15px 0px; -webkit-margin-before: 0px;" class="">Hi Robert,</p><p style="margin: 15px 0px;" class="">I’m trying to understand the impact of your proposal and the feature you want to remove from the language. Could you describe a little more on how if ever this affects tuple destructuring?<span class="Apple-converted-space"> </span></p><pre style="margin: 15px 0px; font-family: Menlo, Consolas, 'Liberation Mono', Courier, monospace; font-size: 10pt; border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; background-color: rgb(248, 248, 248); color: inherit; border: 1px solid rgb(204, 204, 204); overflow: auto; padding: 4px 8px; word-break: normal; word-wrap: normal;" class=""><code class="swift" style="font-family: Menlo, Consolas, 'Liberation Mono', Courier, monospace; font-size: 10pt; border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; background-color: rgb(248, 248, 248); color: inherit; border: 0px; margin: 0px; padding: 0px; word-break: normal; word-wrap: normal; -webkit-margin-before: 0px;">var (a, b, c) = (0, "", 0)
(a, b) = (42, "Hello Swift")
(a = 42, b = "Hello Swift")
var (x, y) = (0, 42)
(x, y) = (y, x) // swap without a temporary value
</code></pre><div style="margin: 15px 0px;" class=""><br class="webkit-block-placeholder"></div></div><div class="bloop_original_html" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(254, 254, 254);"><div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; margin: 0px;" class=""><br class=""></div><br class=""><div id="bloop_sign_1493961127118854912" class="bloop_sign"><div style="font-family: helvetica, arial; font-size: 13px;" class="">-- <br class="">Adrian Zubarev<br class="">Sent with Airmail</div></div><br class=""><p class="airmail_on" style="margin: 15px 0px;">Am 5. Mai 2017 um 04:15:12, Robert Widmann via swift-evolution (<a href="mailto:swift-evolution@swift.org" style="color: rgb(65, 131, 196); background-color: inherit; text-decoration: none;" class="">swift-evolution@swift.org</a>) schrieb:</p><blockquote type="cite" class="clean_bq" style="margin: 15px 0px;"><span style="margin-top: 0px; margin-bottom: 0px;" class=""><div class="" style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><div class=""></div><div class="">Hi all,<div class=""><br class=""></div><div class="">So sorry that this proposal comes so late in the game, but I feel it’s too important not to bring it to the attention of the community now. Attached is a proposal to deprecate a language feature many of you will probably have never had the chance to use: Tuple Shuffles. I’ve attached a copy of the first draft of the proposal below, but the latest copy can be read on <a href="https://github.com/apple/swift-evolution/pull/705/files" class="" style="color: rgb(65, 131, 196); background-color: inherit; text-decoration: none;">Github</a>.</div><div class=""><br class=""></div><div class="">Thanks!</div><div class=""><br class=""></div><div class="">~Robert Widmann</div><div class=""><br class=""></div><div class=""><h1 class="" style="font-weight: bold; color: rgb(36, 41, 46); font-size: 28pt; box-sizing: border-box; margin-right: 0px; margin-bottom: 16px; margin-left: 0px; line-height: 1.25; padding-bottom: 0.3em; border-bottom-width: 1px; border-bottom-style: solid; border-bottom-color: rgb(234, 236, 239); font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; background-color: rgb(255, 255, 255); margin-top: 0px !important;">Deprecate Tuple Shuffles</h1><ul class="" style="margin: 0px 0px 16px; box-sizing: border-box; padding-left: 2em; color: rgb(36, 41, 46); font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; font-size: 16px; background-color: rgb(255, 255, 255);"><li class="" style="margin: 15px 0px; box-sizing: border-box;">Proposal: <a href="https://github.com/CodaFi/swift-evolution/blob/8eaf320b3c2a117909fc0269c398e89c033a4b9f/proposals/NNNN-filename.md" class="" style="color: rgb(3, 102, 214); background-color: transparent; text-decoration: none; box-sizing: border-box; -webkit-text-decoration-skip: objects;">SE-NNNN</a></li><li class="" style="margin: 0.25em 0px 15px; box-sizing: border-box;">Authors: <a href="https://github.com/codafi" class="" style="color: rgb(3, 102, 214); background-color: transparent; text-decoration: none; box-sizing: border-box; -webkit-text-decoration-skip: objects;">Robert Widmann</a></li><li class="" style="margin: 0.25em 0px 15px; box-sizing: border-box;">Review Manager: TBD</li><li class="" style="margin: 0.25em 0px 15px; box-sizing: border-box;">Status: <span class="" style="box-sizing: border-box; font-weight: 600;">Awaiting review</span></li></ul><h2 class="" style="font-weight: bold; border-bottom-width: 1px; border-bottom-style: solid; border-bottom-color: rgb(234, 236, 239); color: rgb(36, 41, 46); font-size: 24px; box-sizing: border-box; margin-top: 24px; margin-bottom: 16px; line-height: 1.25; padding-bottom: 0.3em; font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; background-color: rgb(255, 255, 255);"><a id="user-content-introduction" class="anchor" href="https://github.com/CodaFi/swift-evolution/blob/8eaf320b3c2a117909fc0269c398e89c033a4b9f/proposals/NNNN-deprecate-tuple-shuffles.md#introduction" aria-hidden="true" style="color: rgb(3, 102, 214); background-color: transparent; text-decoration: none; box-sizing: border-box; -webkit-text-decoration-skip: objects; float: left; padding-right: 4px; margin-left: -20px; line-height: 1;"><svg aria-hidden="true" class="octicon octicon-link" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Introduction</h2><p class="" style="margin: 0px 0px 16px; box-sizing: border-box; color: rgb(36, 41, 46); font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; font-size: 16px; background-color: rgb(255, 255, 255);">This proposal seeks the deprecation of a little-known feature of Swift called a "Tuple Shuffle".</p><h2 class="" style="font-weight: bold; border-bottom-width: 1px; border-bottom-style: solid; border-bottom-color: rgb(234, 236, 239); color: rgb(36, 41, 46); font-size: 24px; box-sizing: border-box; margin-top: 24px; margin-bottom: 16px; line-height: 1.25; padding-bottom: 0.3em; font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; background-color: rgb(255, 255, 255);"><a id="user-content-motivation" class="anchor" href="https://github.com/CodaFi/swift-evolution/blob/8eaf320b3c2a117909fc0269c398e89c033a4b9f/proposals/NNNN-deprecate-tuple-shuffles.md#motivation" aria-hidden="true" style="color: rgb(3, 102, 214); background-color: transparent; text-decoration: none; box-sizing: border-box; -webkit-text-decoration-skip: objects; float: left; padding-right: 4px; margin-left: -20px; line-height: 1;"><svg aria-hidden="true" class="octicon octicon-link" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Motivation</h2><p class="" style="margin: 0px 0px 16px; box-sizing: border-box; color: rgb(36, 41, 46); font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; font-size: 16px; background-color: rgb(255, 255, 255);">A tuple-shuffle is an undocumented feature of Swift in which one can re-order the indices of a tuple by writing a pattern that describes a permutation in a syntax reminiscent of adding type-annotations to a parameter list:</p><div class="highlight highlight-source-swift" style="box-sizing: border-box; margin-bottom: 16px; color: rgb(36, 41, 46); font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; font-size: 16px; background-color: rgb(255, 255, 255);"><pre class="" style="margin: 0px; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 13.600000381469727px; border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; background-color: rgb(246, 248, 250); color: inherit; border: 1px solid rgb(204, 204, 204); overflow: auto; padding: 16px; word-break: normal; word-wrap: normal; box-sizing: border-box; line-height: 1.45;"><span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">let</span> a <span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">=</span> (<span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">x</span>: <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">1</span>, <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">y</span>: <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">2</span>)
<span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">var</span> b<span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">:</span> (<span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">y</span>: <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">Int</span>, <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">x</span>: <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">Int</span>)
b <span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">=</span> a</pre></div><p class="" style="margin: 0px 0px 16px; box-sizing: border-box; color: rgb(36, 41, 46); font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; font-size: 16px; background-color: rgb(255, 255, 255);">It can be used to simultaneously destructure and reorder a tuple:</p><div class="highlight highlight-source-swift" style="box-sizing: border-box; margin-bottom: 16px; color: rgb(36, 41, 46); font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; font-size: 16px; background-color: rgb(255, 255, 255);"><pre class="" style="margin: 0px; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 13.600000381469727px; border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; background-color: rgb(246, 248, 250); color: inherit; border: 1px solid rgb(204, 204, 204); overflow: auto; padding: 16px; word-break: normal; word-wrap: normal; box-sizing: border-box; line-height: 1.45;"><span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">let</span> tuple <span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">=</span> (<span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">first</span>: <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">0</span>, <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">second</span>: (<span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">x</span>: <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">1</span>, <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">y</span>: <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">2</span>))
<span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">let</span> (<span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">second</span>: (<span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">x</span>: b, <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">y</span>: c), <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">first</span>: a) <span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">=</span> tuple</pre></div><p class="" style="margin: 0px 0px 16px; box-sizing: border-box; color: rgb(36, 41, 46); font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; font-size: 16px; background-color: rgb(255, 255, 255);">It can also be used to map parameter labels out of order in a call expression:</p><div class="highlight highlight-source-swift" style="box-sizing: border-box; margin-bottom: 16px; color: rgb(36, 41, 46); font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; font-size: 16px; background-color: rgb(255, 255, 255);"><pre class="" style="margin: 0px; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 13.600000381469727px; border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; background-color: rgb(246, 248, 250); color: inherit; border: 1px solid rgb(204, 204, 204); overflow: auto; padding: 16px; word-break: normal; word-wrap: normal; box-sizing: border-box; line-height: 1.45;"><span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">func</span> <span class="pl-en" style="box-sizing: border-box; color: rgb(121, 93, 163);">foo</span>(<span class="pl-smi" style="box-sizing: border-box; color: rgb(51, 51, 51);"><span class="pl-en" style="box-sizing: border-box; color: rgb(121, 93, 163);">_</span></span> : (x : <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">Int</span>, y : <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">Int</span>)) {}
<span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">foo</span>((<span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">y</span>: <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">5</span>, <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">x</span>: <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">10</span>)) <span class="pl-c" style="box-sizing: border-box; color: rgb(150, 152, 150);"><span class="pl-c" style="box-sizing: border-box;">//</span> Valid</span></pre></div><p class="" style="margin: 0px 0px 16px; box-sizing: border-box; color: rgb(36, 41, 46); font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; font-size: 16px; background-color: rgb(255, 255, 255);">Note that a tuple shuffle is distinct from a re-assignment through a tuple pattern. For example, this series of statements will continue to function as before:</p><div class="highlight highlight-source-swift" style="box-sizing: border-box; margin-bottom: 16px; color: rgb(36, 41, 46); font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; font-size: 16px; background-color: rgb(255, 255, 255);"><pre class="" style="margin: 0px; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 13.600000381469727px; border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; background-color: rgb(246, 248, 250); color: inherit; border: 1px solid rgb(204, 204, 204); overflow: auto; padding: 16px; word-break: normal; word-wrap: normal; box-sizing: border-box; line-height: 1.45;"><span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">var</span> x <span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">=</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">5</span>
<span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">var</span> y <span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">=</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">10</span>
<span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">var</span> z <span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">=</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">15</span>
(z, y, x) <span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">=</span> (x, z, y)</pre></div><p class="" style="margin: 0px 0px 16px; box-sizing: border-box; color: rgb(36, 41, 46); font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; font-size: 16px; background-color: rgb(255, 255, 255);">Their inclusion in the language complicates every part of the compiler stack, uses a <a href="https://twitter.com/CodaFi_/status/860246169854894081" class="" style="color: rgb(3, 102, 214); background-color: transparent; text-decoration: none; box-sizing: border-box; -webkit-text-decoration-skip: objects;">syntax that can be confused for type annotations</a>, contradicts the goals of earlier SE's (see <a href="https://github.com/apple/swift-evolution/blob/9cf2685293108ea3efcbebb7ee6a8618b83d4a90/proposals/0060-defaulted-parameter-order.md" class="" style="color: rgb(3, 102, 214); background-color: transparent; text-decoration: none; box-sizing: border-box; -webkit-text-decoration-skip: objects;">SE-0060</a>), and makes non-sensical patterns possible in surprising places.</p><p class="" style="margin: 0px 0px 16px; box-sizing: border-box; color: rgb(36, 41, 46); font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; font-size: 16px; background-color: rgb(255, 255, 255);">Take switch-statements, for example:</p><div class="highlight highlight-source-swift" style="box-sizing: border-box; margin-bottom: 16px; color: rgb(36, 41, 46); font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; font-size: 16px; background-color: rgb(255, 255, 255);"><pre class="" style="margin: 0px; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 13.600000381469727px; border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; background-color: rgb(246, 248, 250); color: inherit; border: 1px solid rgb(204, 204, 204); overflow: auto; padding: 16px; word-break: normal; word-wrap: normal; box-sizing: border-box; line-height: 1.45;"><span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">switch</span> ((<span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">0</span>, <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">0</span>), <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">0</span>){
<span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">case</span> (<span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">_</span> : <span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">let</span> (y, z), <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 134, 179);">_</span> : <span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">let</span> s)<span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">:</span> () <span class="pl-c" style="box-sizing: border-box; color: rgb(150, 152, 150);"><span class="pl-c" style="box-sizing: border-box;">//</span> We are forbidden from giving these patterns names other than "_" </span>
<span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">default</span><span class="pl-k" style="box-sizing: border-box; color: rgb(167, 29, 93);">:</span> ()
}</pre></div><p class="" style="margin: 0px 0px 16px; box-sizing: border-box; color: rgb(36, 41, 46); font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; font-size: 16px; background-color: rgb(255, 255, 255);">This proposal seeks to deprecate them in Swift 3 compatibility mode and enforce that deprecation as a hard error in Swift 4 to facilitate their eventual removal from the language.</p><h2 class="" style="font-weight: bold; border-bottom-width: 1px; border-bottom-style: solid; border-bottom-color: rgb(234, 236, 239); color: rgb(36, 41, 46); font-size: 24px; box-sizing: border-box; margin-top: 24px; margin-bottom: 16px; line-height: 1.25; padding-bottom: 0.3em; font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; background-color: rgb(255, 255, 255);"><a id="user-content-proposed-solution" class="anchor" href="https://github.com/CodaFi/swift-evolution/blob/8eaf320b3c2a117909fc0269c398e89c033a4b9f/proposals/NNNN-deprecate-tuple-shuffles.md#proposed-solution" aria-hidden="true" style="color: rgb(3, 102, 214); background-color: transparent; text-decoration: none; box-sizing: border-box; -webkit-text-decoration-skip: objects; float: left; padding-right: 4px; margin-left: -20px; line-height: 1;"><svg aria-hidden="true" class="octicon octicon-link" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Proposed solution</h2><p class="" style="margin: 0px 0px 16px; box-sizing: border-box; color: rgb(36, 41, 46); font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; font-size: 16px; background-color: rgb(255, 255, 255);">Construction of Tuple Shuffle Expressions will become a warning in Swift 3 compatibility mode and will be a hard-error in Swift 4.</p><h2 class="" style="font-weight: bold; border-bottom-width: 1px; border-bottom-style: solid; border-bottom-color: rgb(234, 236, 239); color: rgb(36, 41, 46); font-size: 24px; box-sizing: border-box; margin-top: 24px; margin-bottom: 16px; line-height: 1.25; padding-bottom: 0.3em; font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; background-color: rgb(255, 255, 255);"><a id="user-content-detailed-design" class="anchor" href="https://github.com/CodaFi/swift-evolution/blob/8eaf320b3c2a117909fc0269c398e89c033a4b9f/proposals/NNNN-deprecate-tuple-shuffles.md#detailed-design" aria-hidden="true" style="color: rgb(3, 102, 214); background-color: transparent; text-decoration: none; box-sizing: border-box; -webkit-text-decoration-skip: objects; float: left; padding-right: 4px; margin-left: -20px; line-height: 1;"><svg aria-hidden="true" class="octicon octicon-link" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Detailed design</h2><p class="" style="margin: 0px 0px 16px; box-sizing: border-box; color: rgb(36, 41, 46); font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; font-size: 16px; background-color: rgb(255, 255, 255);">In addition to the necessary diagnostics, the grammar will be ammended to simplify the following productions:</p><div class="highlight highlight-source-diff" style="box-sizing: border-box; margin-bottom: 16px; color: rgb(36, 41, 46); font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; font-size: 16px; background-color: rgb(255, 255, 255);"><pre class="" style="margin: 0px; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 13.600000381469727px; border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; background-color: rgb(246, 248, 250); color: inherit; border: 1px solid rgb(204, 204, 204); overflow: auto; padding: 16px; word-break: normal; word-wrap: normal; box-sizing: border-box; line-height: 1.45;">tuple-pattern → (tuple-pattern-element-list <opt>)
tuple-pattern-element-list → tuple-pattern-element | tuple-pattern-element , tuple-pattern-element-list
<span class="pl-md" style="box-sizing: border-box; color: rgb(189, 44, 0); background-color: rgb(255, 236, 236);"><span class="pl-md" style="box-sizing: border-box;">-</span> tuple-pattern-element → pattern | identifier:pattern</span>
<span class="pl-mi1" style="box-sizing: border-box; color: rgb(85, 165, 50); background-color: rgb(234, 255, 234);"><span class="pl-mi1" style="box-sizing: border-box;">+</span> tuple-pattern-element → pattern</span></pre></div><h2 class="" style="font-weight: bold; border-bottom-width: 1px; border-bottom-style: solid; border-bottom-color: rgb(234, 236, 239); color: rgb(36, 41, 46); font-size: 24px; box-sizing: border-box; margin-top: 24px; margin-bottom: 16px; line-height: 1.25; padding-bottom: 0.3em; font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; background-color: rgb(255, 255, 255);"><a id="user-content-impact-on-existing-code" class="anchor" href="https://github.com/CodaFi/swift-evolution/blob/8eaf320b3c2a117909fc0269c398e89c033a4b9f/proposals/NNNN-deprecate-tuple-shuffles.md#impact-on-existing-code" aria-hidden="true" style="color: rgb(3, 102, 214); background-color: transparent; text-decoration: none; box-sizing: border-box; -webkit-text-decoration-skip: objects; float: left; padding-right: 4px; margin-left: -20px; line-height: 1;"><svg aria-hidden="true" class="octicon octicon-link" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Impact on Existing Code</h2><p class="" style="margin: 0px 0px 16px; box-sizing: border-box; color: rgb(36, 41, 46); font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; font-size: 16px; background-color: rgb(255, 255, 255);">Because very little code is intentionally using Tuple Shuffles, impact on existing code will be negligible but not non-zero.</p><h2 class="" style="font-weight: bold; border-bottom-width: 1px; border-bottom-style: solid; border-bottom-color: rgb(234, 236, 239); color: rgb(36, 41, 46); font-size: 24px; box-sizing: border-box; margin-top: 24px; margin-bottom: 16px; line-height: 1.25; padding-bottom: 0.3em; font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; background-color: rgb(255, 255, 255);"><a id="user-content-alternatives-considered" class="anchor" href="https://github.com/CodaFi/swift-evolution/blob/8eaf320b3c2a117909fc0269c398e89c033a4b9f/proposals/NNNN-deprecate-tuple-shuffles.md#alternatives-considered" aria-hidden="true" style="color: rgb(3, 102, 214); background-color: transparent; text-decoration: none; box-sizing: border-box; -webkit-text-decoration-skip: objects; float: left; padding-right: 4px; margin-left: -20px; line-height: 1;"><svg aria-hidden="true" class="octicon octicon-link" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Alternatives considered</h2><div class="" style="box-sizing: border-box; margin-top: 0px; color: rgb(36, 41, 46); font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol'; font-size: 16px; background-color: rgb(255, 255, 255); margin-bottom: 0px !important;">Continue to keep the architecture in place to facilitate this feature.</div></div>_______________________________________________<br class="">swift-evolution mailing list<br class=""><a href="mailto:swift-evolution@swift.org" style="color: rgb(65, 131, 196); background-color: inherit; text-decoration: none;" class="">swift-evolution@swift.org</a><br class=""><a href="https://lists.swift.org/mailman/listinfo/swift-evolution" style="color: rgb(65, 131, 196); background-color: inherit; text-decoration: none;" class="">https://lists.swift.org/mailman/listinfo/swift-evolution</a><br class=""></div></div></span></blockquote></div><div class="bloop_markdown" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(254, 254, 254);"></div></div></blockquote></div><br class=""></div></body></html>