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.send { color:#77bb77; }
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.error { color:#AA0000; }</style></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><div class="bloop_markdown"><p>I’m not arguing to remove all labels in Swift. Labels are great, this is a fact for sure. The point I was trying to make is that labels in tuples how either a meaning or not at all.</p>
<pre><code class="swift">// This is a shortcut for the tuple type `(x: Int, y: Int)`
let foo = (x: 0, y: 0)
// In this case the labels are only used for description,
// they do not server any benefit here are most likely redundant
let (x: x, y: y) = foo
</code></pre>
<p>Labels elsewhere are a different story and I do support the cosmetic addition Chris Lattner sketched out here: <a href="https://lists.swift.org/pipermail/swift-evolution-announce/2016-July/000233.html">https://lists.swift.org/pipermail/swift-evolution-announce/2016-July/000233.html</a></p>
<p>However this is about closures and not tuples, I don’t think this would anyhow affect the removal of labels in tuple destructuring.</p>
<p>Plus I don’t see this to create an inconsistent in Swift, because as I already said, labels in tuple destructuring are useless.</p>
<p></p></div><div class="bloop_original_html"><style>body{font-family:Helvetica,Arial;font-size:13px}</style><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px; color: rgba(0,0,0,1.0); margin: 0px; line-height: auto;"><br></div> <br> <div id="bloop_sign_1493968921029430016" class="bloop_sign"><div style="font-family:helvetica,arial;font-size:13px">-- <br>Adrian Zubarev<br>Sent with Airmail</div></div> <br><p class="airmail_on">Am 5. Mai 2017 um 09:20:49, Xiaodi Wu (<a href="mailto:xiaodi.wu@gmail.com">xiaodi.wu@gmail.com</a>) schrieb:</p> <blockquote type="cite" class="clean_bq"><span><div><div></div><div>
<title></title>
<div dir="ltr">On Fri, May 5, 2017 at 2:04 AM, Adrian Zubarev
<span dir="ltr"><<a href="mailto:adrian.zubarev@devandartist.com" target="_blank">adrian.zubarev@devandartist.com</a>></span>
wrote:<br>
<div class="gmail_extra">
<div class="gmail_quote">
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div style="word-wrap:break-word">
<div class="m_-5961184854423040877bloop_markdown">
<p>Personally I don’t see the latter as an issue, at least not in
that particular example of yours, because you can always look up
the type of your labeled tuple.</p>
</div>
</div>
</blockquote>
<div>That's an argument that can be made for nearly all labels in
the language, is it not? Function argument labels could be entirely
removed, by your argument, since parameter names are completely
visible in the documentation and you can always just look it up.
Consider the rationale behind revising SE-0111 expressly to allow
"cosmetic" labels. As I said, many languages don't have labels, but
Swift does.</div>
<div><br></div>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div style="word-wrap:break-word">
<div class="m_-5961184854423040877bloop_markdown">
<hr>
<p>Is there any benefit gained from labels in tuple destructuring?
<code>let (x: x, y: y)</code> is redundant to my eyes. If we ban
reordering now, than I don’t see choosing different names in tuple
destructuring as a strong argument of allowing labels there
<code>let (x: a, y: b)</code>. They’re literally the same as one
would write comments inside the destructured tuple <code>let (/* my
x */ x, /* my y*/ y)</code>.</p>
</div>
</div>
</blockquote>
<div>If you look in the C++ parts of the Swift compiler, that's the
style for arguments in function calls where in Swift we use
argument labels. Same idea. Your argument would remove most if not
all labels from the language.</div>
<div><br></div>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div style="word-wrap:break-word">
<div class="m_-5961184854423040877bloop_markdown"></div>
<div class="m_-5961184854423040877bloop_original_html">
<div id="m_-5961184854423040877bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px;color:rgba(0,0,0,1.0);margin:0px;line-height:auto">
<span class=""><br></span></div>
<span class=""><br></span>
<div id="m_-5961184854423040877bloop_sign_1493967085779695872" class="m_-5961184854423040877bloop_sign">
<div style="font-family:helvetica,arial;font-size:13px">
<span class="">-- <br>
Adrian Zubarev<br>
Sent with Airmail</span></div>
</div>
<span class=""><br></span>
<p class="m_-5961184854423040877airmail_on"><span class="">Am 5.
Mai 2017 um 08:36:20, Xiaodi Wu via swift-evolution (<a href="mailto:swift-evolution@swift.org" target="_blank">swift-evolution@swift.org</a>) schrieb:</span></p>
<blockquote type="cite" class="m_-5961184854423040877clean_bq">
<div>
<div style="color:rgb(0,0,0);font-family:helvetica;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">
<span class="">```</span></div>
<div style="color:rgb(0,0,0);font-family:helvetica;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">
<span class="">let tuple = (x: 1, y: 2)</span></div>
<div style="color:rgb(0,0,0);font-family:helvetica;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">
<span class=""><br></span></div>
<div style="color:rgb(0,0,0);font-family:helvetica;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">
<span class="">// I, silly human, mistakenly think the elements in
the tuple are</span></div>
<div style="color:rgb(0,0,0);font-family:helvetica;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">
<span class="">// `y` first, then `x`. I'm a confused human. Now I
write:</span></div>
<div style="color:rgb(0,0,0);font-family:helvetica;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">
<span class=""><br></span></div>
<div style="color:rgb(0,0,0);font-family:helvetica;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">
<span class="">let (y: y, x: x) = tuple<br></span></div>
<div style="color:rgb(0,0,0);font-family:helvetica;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">
<span class="">// Currently, does the right thing, even though I'm
confused.</span></div>
<div style="color:rgb(0,0,0);font-family:helvetica;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">
<span class=""><br></span></div>
<div style="color:rgb(0,0,0);font-family:helvetica;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">
<span class="">let (y: y, x: x) = tuple</span></div>
<div style="color:rgb(0,0,0);font-family:helvetica;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">
<span class="">// Without tuple reordering, this produces an error,
which corrects my confusion.</span></div>
<div style="color:rgb(0,0,0);font-family:helvetica;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">
<span class=""><br></span></div>
<div style="color:rgb(0,0,0);font-family:helvetica;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">
<div><span class="">let (y, x) = tuple</span></div>
<div><span class="">// Oops. I'm out of luck.</span></div>
</div>
<div style="color:rgb(0,0,0);font-family:helvetica;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">
<span class="">```</span></div>
</div>
</blockquote>
</div>
<div class="m_-5961184854423040877bloop_markdown"></div>
</div>
</blockquote>
</div>
<br></div>
</div>
</div></div></span></blockquote></div><div class="bloop_markdown"><p></p></div></body></html>