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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>–1 for me, I’ll explain in a moment.</p>
<p>To help you find the old topic you can use the <strong>proof-of-concept</strong> Discourse setup from Nate Cook: <a href="http://discourse.natecook.com/t/proposal-variadics-as-attribute/2075/20">http://discourse.natecook.com/t/proposal-variadics-as-attribute/2075/20</a></p>
<p>The link above also reflects Chris Lattners opinion on this topic.</p>
<hr>
<p>I gave the topic a down vote not because I don’t like the proposal, but because I personally see variadics go into the direction of tuples. Especially I’d love to see some more talk about tuples in combination of generic variadics (see here: <a href="https://github.com/apple/swift/blob/master/docs/GenericsManifesto.md#variadic-generics">https://github.com/apple/swift/blob/master/docs/GenericsManifesto.md#variadic-generics</a>).</p>
<p>There is a lot of design overlap. That is the reason why I think we should vision variadics as a whole in its future rather than simply repaint <code>…</code> postfix to a type annotation keyword <code>@variadics</code>. This will only close the doors for some features we might want to add in a future version of Swift.</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_1487160306715163904" 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 15. Februar 2017 um 12:43:49, Haravikk via swift-evolution (<a href="mailto:swift-evolution@swift.org">swift-evolution@swift.org</a>) schrieb:</p> <blockquote type="cite" class="clean_bq"><span><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div></div><div>
<title></title>
<div class="">Immediate followup, but is there something wrong with
the gmane site that we've been using to provide links to mailing
list discussions?</div>
<div class="">I can't seem to get a list of recent topics so I can
find out what the new discussion link should be.</div>
<br class="">
<div>
<blockquote type="cite" class="">
<div class="">On 15 Feb 2017, at 11:38, Haravikk 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="">
<div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">I'm posting this as a new discussion topic for my earlier
proposal of Variadics as an Attribute. I would have reused the old
topic but I have no idea how to do that on a mailing list once the
messages are gone (I don't keep them for long); I'm looking forward
to the possible switch to Discourse!
<div class=""><br class=""></div>
<div class="">The idea behind the proposal is fairly simple; to do
away with the current unique syntax for declaring variadic
functions/methods, while retaining the ability to call methods in
the same way. In other words, instead of declaring a method with an
ellipsis, you would declare it just like any other method, but add
the @variadic attribute, enabling the ability to call it just like
you would call a variadic now.</div>
<div class=""><br class=""></div>
<div class="">Since this isn't strictly a code-breaking change
(existing code can be converted automatically) I'm unsure of when
to issue a new pull request, so I'll stick with a discussion to
hammer out any lingering issues with the proposal for just now.
Here it is:</div>
<div class=""><br class=""></div>
<div class=""><a href="https://github.com/Haravikk/swift-evolution/blob/1d3c09f1c6f3e6dc502ef84538d197a02bed904e/proposals/nnnn-variadics-as-attribute.md" class="">https://github.com/Haravikk/swift-evolution/blob/1d3c09f1c6f3e6dc502ef84538d197a02bed904e/proposals/nnnn-variadics-as-attribute.md</a></div>
<div class=""><br class=""></div>
<div class="">
<h1 style="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(238, 238, 238); color: rgb(51, 51, 51); 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;" class="">Variadics as Attribute</h1>
<h1 style="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(238, 238, 238); color: rgb(51, 51, 51); 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;" class=""></h1>
<ul style="box-sizing: border-box; padding-left: 2em; margin-top: 0px; margin-bottom: 16px; font-size: 16px; font-weight: normal;" class="">
<li style="box-sizing: border-box;" class="">
Proposal: <a href="https://github.com/Haravikk/swift-evolution/blob/master/proposals/nnnn-variadics-as-attribute.md" style="box-sizing: border-box; background-color: transparent; -webkit-text-decoration-skip: objects; color: rgb(64, 120, 192); text-decoration: none;" class="">SE-NNNN</a></li>
<li style="box-sizing: border-box; margin-top: 0.25em;" class="">
Author: <a href="https://github.com/haravikk" style="box-sizing: border-box; background-color: transparent; -webkit-text-decoration-skip: objects; color: rgb(64, 120, 192); text-decoration: none;" class="">Haravikk</a></li>
<li style="box-sizing: border-box; margin-top: 0.25em;" class="">
Status: <span style="box-sizing: border-box; font-weight: 600;" class="">Awaiting
review</span></li>
<li style="box-sizing: border-box; margin-top: 0.25em;" class="">
Review manager: TBD</li>
</ul>
<h2 style="box-sizing: border-box; margin-top: 24px; margin-bottom: 16px; line-height: 1.25; padding-bottom: 0.3em; border-bottom-width: 1px; border-bottom-style: solid; border-bottom-color: rgb(238, 238, 238); color: rgb(51, 51, 51); 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);" class=""><a id="user-content-introduction" class="anchor" href="https://github.com/Haravikk/swift-evolution/blob/master/proposals/nnnn-variadics-as-attribute.md#introduction" aria-hidden="true" style="box-sizing: border-box; background-color: transparent; -webkit-text-decoration-skip: objects; color: rgb(64, 120, 192); text-decoration: none; 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>
<h1 style="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(238, 238, 238); color: rgb(51, 51, 51); 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;" class=""></h1>
<p style="box-sizing: border-box; margin-top: 0px; margin-bottom: 16px; font-size: 16px; font-weight: normal;" class="">This proposal seeks to redesign the current, unique
variadic function declaration syntax to use an attribute instead,
with a goal of unifying standard and variadic function
declarations.</p>
<h2 style="box-sizing: border-box; margin-top: 24px; margin-bottom: 16px; line-height: 1.25; padding-bottom: 0.3em; border-bottom-width: 1px; border-bottom-style: solid; border-bottom-color: rgb(238, 238, 238); color: rgb(51, 51, 51); 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);" class=""><a id="user-content-motivation" class="anchor" href="https://github.com/Haravikk/swift-evolution/blob/master/proposals/nnnn-variadics-as-attribute.md#motivation" aria-hidden="true" style="box-sizing: border-box; background-color: transparent; -webkit-text-decoration-skip: objects; color: rgb(64, 120, 192); text-decoration: none; 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>
<h1 style="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(238, 238, 238); color: rgb(51, 51, 51); 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;" class=""></h1>
<p style="box-sizing: border-box; margin-top: 0px; margin-bottom: 16px; font-size: 16px; font-weight: normal;" class="">Variadics are essentially a call-site feature enabling a
function to be called as if it is being provided with multiple
arguments, rather than a single list argument. However instead of
being implemented as some kind of switch, variadics have a unique
declaration syntax that separates them uncessarily from standard
function declarations. Currently this also means that redundancy is
required in order to allow a function to be called both with an
explicit array, and in the variadic style.</p>
<h2 style="box-sizing: border-box; margin-top: 24px; margin-bottom: 16px; line-height: 1.25; padding-bottom: 0.3em; border-bottom-width: 1px; border-bottom-style: solid; border-bottom-color: rgb(238, 238, 238); color: rgb(51, 51, 51); 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);" class=""><a id="user-content-proposed-solution" class="anchor" href="https://github.com/Haravikk/swift-evolution/blob/master/proposals/nnnn-variadics-as-attribute.md#proposed-solution" aria-hidden="true" style="box-sizing: border-box; background-color: transparent; -webkit-text-decoration-skip: objects; color: rgb(64, 120, 192); text-decoration: none; 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>
<h1 style="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(238, 238, 238); color: rgb(51, 51, 51); 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;" class=""></h1>
<p style="box-sizing: border-box; margin-top: 0px; margin-bottom: 16px; font-size: 16px; font-weight: normal;" class="">To unify both regular and variadic function declarations
this proposal seeks to replace the unique trailing elipsis
declaration syntax with a new <code style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 14px; padding: 0.2em 0px; margin: 0px; background-color: rgba(0, 0, 0, 0.0392157); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px;" class="">@variadic</code> attribute on regular function
declarations, enabling optional variadic syntax at the call
site.</p>
<p style="box-sizing: border-box; margin-top: 0px; margin-bottom: 16px; font-size: 16px; font-weight: normal;" class="">In short this proposal would replace:</p>
<pre style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 14px; margin-top: 0px; margin-bottom: 16px; font-weight: normal; line-height: 1.45; word-wrap: normal; padding: 16px; overflow: auto; background-color: rgb(247, 247, 247); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px;" class=""><code style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; padding: 0px; margin: 0px; background-color: transparent; border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; word-break: normal; border: 0px; display: inline; overflow: visible; line-height: inherit; word-wrap: normal;" class="">func someFunc(_ values:Int...) { … }
</code></pre>
<p style="box-sizing: border-box; margin-top: 0px; margin-bottom: 16px; font-size: 16px; font-weight: normal;" class="">With the following:</p>
<pre style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 14px; margin-top: 0px; margin-bottom: 16px; font-weight: normal; line-height: 1.45; word-wrap: normal; padding: 16px; overflow: auto; background-color: rgb(247, 247, 247); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px;" class=""><code style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; padding: 0px; margin: 0px; background-color: transparent; border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; word-break: normal; border: 0px; display: inline; overflow: visible; line-height: inherit; word-wrap: normal;" class="">func someFunc(_ values:@variadic [Int]) { … }
</code></pre>
<h2 style="box-sizing: border-box; margin-top: 24px; margin-bottom: 16px; line-height: 1.25; padding-bottom: 0.3em; border-bottom-width: 1px; border-bottom-style: solid; border-bottom-color: rgb(238, 238, 238); color: rgb(51, 51, 51); 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);" class=""><a id="user-content-detailed-design" class="anchor" href="https://github.com/Haravikk/swift-evolution/blob/master/proposals/nnnn-variadics-as-attribute.md#detailed-design" aria-hidden="true" style="box-sizing: border-box; background-color: transparent; -webkit-text-decoration-skip: objects; color: rgb(64, 120, 192); text-decoration: none; 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>
<h1 style="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(238, 238, 238); color: rgb(51, 51, 51); 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;" class=""></h1>
<p style="box-sizing: border-box; margin-top: 0px; margin-bottom: 16px; font-size: 16px; font-weight: normal;" class="">The trailing elipsis declaration syntax will be removed,
with a fixit providing a replacement to the new attribute-based
syntax. The new <code style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 14px; padding: 0.2em 0px; margin: 0px; background-color: rgba(0, 0, 0, 0.0392157); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px;" class="">@variadic</code> attribute can be placed on any one
function parameter with a type of <code style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 14px; padding: 0.2em 0px; margin: 0px; background-color: rgba(0, 0, 0, 0.0392157); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px;" class="">Array<Foo></code> (or <code style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 14px; padding: 0.2em 0px; margin: 0px; background-color: rgba(0, 0, 0, 0.0392157); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px;" class="">[Foo]</code>), enabling the optional use of variadic
declaration at the call site.</p>
<p style="box-sizing: border-box; margin-top: 0px; margin-bottom: 16px; font-size: 16px; font-weight: normal;" class="">For example:</p>
<pre style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 14px; margin-top: 0px; margin-bottom: 16px; font-weight: normal; line-height: 1.45; word-wrap: normal; padding: 16px; overflow: auto; background-color: rgb(247, 247, 247); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px;" class=""><code style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; padding: 0px; margin: 0px; background-color: transparent; border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; word-break: normal; border: 0px; display: inline; overflow: visible; line-height: inherit; word-wrap: normal;" class="">func someFunc(_ values:@variadic [Int]) { … }
</code></pre>
<p style="box-sizing: border-box; margin-top: 0px; margin-bottom: 16px; font-size: 16px; font-weight: normal;" class="">Can be called in any of the following forms:</p>
<pre style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 14px; margin-top: 0px; margin-bottom: 16px; font-weight: normal; line-height: 1.45; word-wrap: normal; padding: 16px; overflow: auto; background-color: rgb(247, 247, 247); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px;" class=""><code style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; padding: 0px; margin: 0px; background-color: transparent; border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; word-break: normal; border: 0px; display: inline; overflow: visible; line-height: inherit; word-wrap: normal;" class="">someFunc(1, 2, 3, 4, 5) // Fixed length variadic call
someFunc([1, 2, 3, 4, 5]) // Fixed length array call
someFunc(foo) // Dynamic array call passing the Array variable foo
</code></pre>
<h3 style="box-sizing: border-box; margin-top: 24px; margin-bottom: 16px; font-size: 1.25em; line-height: 1.25; color: rgb(51, 51, 51); 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);" class=""><a id="user-content-advantages" class="anchor" href="https://github.com/Haravikk/swift-evolution/blob/master/proposals/nnnn-variadics-as-attribute.md#advantages" aria-hidden="true" style="box-sizing: border-box; background-color: transparent; -webkit-text-decoration-skip: objects; color: rgb(64, 120, 192); text-decoration: none; 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>Advantages</h3>
<h1 style="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(238, 238, 238); color: rgb(51, 51, 51); 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;" class=""></h1>
<ol style="box-sizing: border-box; padding-left: 2em; margin-top: 0px; margin-bottom: 16px; font-size: 16px; font-weight: normal;" class="">
<li style="box-sizing: border-box;" class="">Unifies standard and
variadic function declarations, eliminating a unique syntax that is
arguably unnecessary.</li>
<li style="box-sizing: border-box; margin-top: 0.25em;" class="">
The type of the variadic parameter is absolutely explicit.</li>
<li style="box-sizing: border-box; margin-top: 0.25em;" class="">
Enables calling of a variadic function with dynamic arrays, without
the need for additional special syntax.</li>
<li style="box-sizing: border-box; margin-top: 0.25em;" class="">No
redundant overloads to enable both call styles (one declaration
provides both).</li>
<li style="box-sizing: border-box; margin-top: 0.25em;" class="">
Enables further extension to support more collection types now or
in future (see Proposed Extension below).</li>
<li style="box-sizing: border-box; margin-top: 0.25em;" class="">
Moves the variadic feature declaration from syntax into the
attributes list, which should aid discoverability (and simplify
syntax very slightly).</li>
<li style="box-sizing: border-box; margin-top: 0.25em;" class="">
The attribute is more explicit about what it does (provides a name
that can be searched).</li>
</ol>
<h3 style="box-sizing: border-box; margin-top: 24px; margin-bottom: 16px; font-size: 1.25em; line-height: 1.25; color: rgb(51, 51, 51); 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);" class=""><a id="user-content-ambiguity" class="anchor" href="https://github.com/Haravikk/swift-evolution/blob/master/proposals/nnnn-variadics-as-attribute.md#ambiguity" aria-hidden="true" style="box-sizing: border-box; background-color: transparent; -webkit-text-decoration-skip: objects; color: rgb(64, 120, 192); text-decoration: none; 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>Ambiguity</h3>
<h1 style="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(238, 238, 238); color: rgb(51, 51, 51); 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;" class=""></h1>
<p style="box-sizing: border-box; margin-top: 0px; margin-bottom: 16px; font-size: 16px; font-weight: normal;" class="">One technical issue with this change is the introduction
of ambiguity as follows:</p>
<pre style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 14px; margin-top: 0px; margin-bottom: 16px; font-weight: normal; line-height: 1.45; word-wrap: normal; padding: 16px; overflow: auto; background-color: rgb(247, 247, 247); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px;" class=""><code style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; padding: 0px; margin: 0px; background-color: transparent; border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; word-break: normal; border: 0px; display: inline; overflow: visible; line-height: inherit; word-wrap: normal;" class="">someFunc(_ values:@variadic [Any]) { … }
someFunc([1]) // Is this an array call of [1] or a variadic call of [[1]]?
someFunc(foo) // If foo is an array, is this an array call of foo, or a variadic call of [foo]?
</code></pre>
<p style="box-sizing: border-box; margin-top: 0px; margin-bottom: 16px; font-size: 16px; font-weight: normal;" class="">However, this issue is only exhibited when the type of
variadic is <code style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 14px; padding: 0.2em 0px; margin: 0px; background-color: rgba(0, 0, 0, 0.0392157); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px;" class="">Any</code> (or another type that can represent both
an array of elements and the elements themselves) and only when
there is possibly only a single argument.</p>
<p style="box-sizing: border-box; margin-top: 0px; margin-bottom: 16px; font-size: 16px; font-weight: normal;" class="">The proposed solution to this is to reuse the
new <code style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 14px; padding: 0.2em 0px; margin: 0px; background-color: rgba(0, 0, 0, 0.0392157); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px;" class="">@variadic</code> attribute, plus a <code style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 14px; padding: 0.2em 0px; margin: 0px; background-color: rgba(0, 0, 0, 0.0392157); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px;" class="">@nonVariadic</code> attribute*, enabling
disambiguation like so:</p>
<pre style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 14px; margin-top: 0px; margin-bottom: 16px; font-weight: normal; line-height: 1.45; word-wrap: normal; padding: 16px; overflow: auto; background-color: rgb(247, 247, 247); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px;" class=""><code style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; padding: 0px; margin: 0px; background-color: transparent; border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; word-break: normal; border: 0px; display: inline; overflow: visible; line-height: inherit; word-wrap: normal;" class="">someFunc(@variadic [1]) // Unambiguously a variadic call of [[1]]
someFunc(@nonVariadic [1]) // Unambiguously an array call of [1]
someFunc(@variadic foo) // Unambiguously a variadic call of [foo]
</code></pre>
<p style="box-sizing: border-box; margin-top: 0px; margin-bottom: 16px; font-size: 16px; font-weight: normal;" class="">In the variadic case it could also be possible to use a
trailing comma for disambiguation like so:</p>
<pre style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 14px; margin-top: 0px; margin-bottom: 16px; font-weight: normal; line-height: 1.45; word-wrap: normal; padding: 16px; overflow: auto; background-color: rgb(247, 247, 247); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px;" class=""><code style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; padding: 0px; margin: 0px; background-color: transparent; border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; word-break: normal; border: 0px; display: inline; overflow: visible; line-height: inherit; word-wrap: normal;" class="">someFunc([1],) // Unambiguously a varaidic call of [[1]]
someFunc(foo,) // Unambiguously a variadic call of [foo]
</code></pre>
<p style="box-sizing: border-box; margin-top: 0px; margin-bottom: 16px; font-size: 16px; font-weight: normal;" class="">*These attributes could instead be compiler directives if
that is more appropriate.</p>
<h2 style="box-sizing: border-box; margin-top: 24px; margin-bottom: 16px; line-height: 1.25; padding-bottom: 0.3em; border-bottom-width: 1px; border-bottom-style: solid; border-bottom-color: rgb(238, 238, 238); color: rgb(51, 51, 51); 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);" class=""><a id="user-content-impact-on-existing-code" class="anchor" href="https://github.com/Haravikk/swift-evolution/blob/master/proposals/nnnn-variadics-as-attribute.md#impact-on-existing-code" aria-hidden="true" style="box-sizing: border-box; background-color: transparent; -webkit-text-decoration-skip: objects; color: rgb(64, 120, 192); text-decoration: none; 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>
<h1 style="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(238, 238, 238); color: rgb(51, 51, 51); 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;" class=""></h1>
<p style="box-sizing: border-box; margin-top: 0px; margin-bottom: 16px; font-size: 16px; font-weight: normal;" class="">All existing variadic function function declarations will
be invalidated, either being replaced or producing a fixit to
perform conversion like so:</p>
<pre style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 14px; margin-top: 0px; margin-bottom: 16px; font-weight: normal; line-height: 1.45; word-wrap: normal; padding: 16px; overflow: auto; background-color: rgb(247, 247, 247); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px;" class=""><code style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; padding: 0px; margin: 0px; background-color: transparent; border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; word-break: normal; border: 0px; display: inline; overflow: visible; line-height: inherit; word-wrap: normal;" class="">func someFunc(_ values:Int...) // Before
func someFunc(_ values:@variadic [Int]) // After
</code></pre>
<h2 style="box-sizing: border-box; margin-top: 24px; margin-bottom: 16px; line-height: 1.25; padding-bottom: 0.3em; border-bottom-width: 1px; border-bottom-style: solid; border-bottom-color: rgb(238, 238, 238); color: rgb(51, 51, 51); 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);" class=""><a id="user-content-proposed-extension" class="anchor" href="https://github.com/Haravikk/swift-evolution/blob/master/proposals/nnnn-variadics-as-attribute.md#proposed-extension" aria-hidden="true" style="box-sizing: border-box; background-color: transparent; -webkit-text-decoration-skip: objects; color: rgb(64, 120, 192); text-decoration: none; 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 Extension</h2>
<h1 style="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(238, 238, 238); color: rgb(51, 51, 51); 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;" class=""></h1>
<p style="box-sizing: border-box; margin-top: 0px; margin-bottom: 16px; font-size: 16px; font-weight: normal;" class="">One other advantage of the use of an attribute is the
possibility of allowing variadic enabled functions to accept a
wider range of parameter types. For example, the above examples
could be implemented instead like so:</p>
<pre style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 14px; margin-top: 0px; margin-bottom: 16px; font-weight: normal; line-height: 1.45; word-wrap: normal; padding: 16px; overflow: auto; background-color: rgb(247, 247, 247); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px;" class=""><code style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; padding: 0px; margin: 0px; background-color: transparent; border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; word-break: normal; border: 0px; display: inline; overflow: visible; line-height: inherit; word-wrap: normal;" class="">func someFunc(_ values:@variadic MyArrayLiteralConvertible<Int>) { … } // Type conforming to ArrayLiteralConvertible
func someFunc<I:IteratorProtocol where I.Element == Int>(_ values:@variadic I) { … } // Implementation supports all single and multi-pass types
func someFunc<S:Sequence where S.Iterator.Element == Int>(_ values:@variadic S) { … } // Implementation supports all (probably) multi-pass types
func someFunc<C:Collection where C.Iterator.Element == Int>(_ values:@variadic C) { … } // Implementation supports all guaranteed multi-pass, indexable types with known size
</code></pre>
<p style="box-sizing: border-box; margin-top: 0px; margin-bottom: 16px; font-size: 16px; font-weight: normal;" class="">When a specific type is defined it must conform
to <code style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 14px; padding: 0.2em 0px; margin: 0px; background-color: rgba(0, 0, 0, 0.0392157); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px;" class="">ArrayLiteralConvertible</code> to enable variadic
calls, while generic conformances must be capable of being
satisfied by an <code style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 14px; padding: 0.2em 0px; margin: 0px; background-color: rgba(0, 0, 0, 0.0392157); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px;" class="">Array</code> when called in variadic style. For
example, the latter three examples would all receive
an <code style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 14px; padding: 0.2em 0px; margin: 0px; background-color: rgba(0, 0, 0, 0.0392157); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px;" class="">[Int]</code> when called in variadic style, but can
accept any suitable iterator, sequence or collection when called
dynamically. In other words, when a function is called in variadic
style it is always passed an <code style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 14px; padding: 0.2em 0px; margin: 0px; background-color: rgba(0, 0, 0, 0.0392157); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px;" class="">Array</code>unless its type is <code style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 14px; padding: 0.2em 0px; margin: 0px; background-color: rgba(0, 0, 0, 0.0392157); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px;" class="">ArrayLiteralConvertible</code>, so its supported type(s)
must support this.</p>
<p style="box-sizing: border-box; margin-top: 0px; margin-bottom: 16px; font-size: 16px; font-weight: normal;" class="">This extension has been moved into its own section as it
is not critical to the proposal, however it does represent an
advantage of the attribute based approach, and would be desirable
to have if implementing it is sufficiently easy for it to be done
at the same time.</p>
<h2 style="box-sizing: border-box; margin-top: 24px; margin-bottom: 16px; line-height: 1.25; padding-bottom: 0.3em; border-bottom-width: 1px; border-bottom-style: solid; border-bottom-color: rgb(238, 238, 238); color: rgb(51, 51, 51); 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);" class=""><a id="user-content-alternatives-considered" class="anchor" href="https://github.com/Haravikk/swift-evolution/blob/master/proposals/nnnn-variadics-as-attribute.md#alternatives-considered" aria-hidden="true" style="box-sizing: border-box; background-color: transparent; -webkit-text-decoration-skip: objects; color: rgb(64, 120, 192); text-decoration: none; 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">
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</svg></a>Alternatives considered</h2>
<h1 style="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(238, 238, 238); color: rgb(51, 51, 51); 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;" class=""></h1>
<p style="box-sizing: border-box; margin-top: 0px; margin-bottom: 16px; font-size: 16px; font-weight: normal;" class="">One alternative often mentioned is simply enabling the
existing variadic declarations to be called with an array. However,
this has the same issue with ambiguity to resolve, and leaves
variadics as their own category of function, rather than unifying
them with ordinary functions.</p>
<p style="box-sizing: border-box; margin-top: 0px; margin-bottom: 16px; font-size: 16px; font-weight: normal;" class="">It is possible to both add the <code style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 14px; padding: 0.2em 0px; margin: 0px; background-color: rgba(0, 0, 0, 0.0392157); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px;" class="">@variadic</code> attribute and retain the current
syntax as a shorthand, however if the proposed extension is
implemented this would discourage consideration of the best
collection type to use, and in general it would remove one
advantage in removing this extraneous syntax.</p>
<div style="box-sizing: border-box; margin-top: 0px; font-size: 16px; font-weight: normal; margin-bottom: 0px !important;" class="">The nuclear option is to remove variadics entirely; this
is the preference of some (myself included) as it eliminates the
inherent ambiguity of variadics in general, forcing explicit use of
arrays and other types with no need for limitations, however there
is sufficient support for variadics now that they exist that this
option is unlikely to succeed.</div>
</div>
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