<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 Apr 19, 2016, at 9:44 AM, David Rönnqvist <<a href="mailto:david.ronnqvist@gmail.com" class="">david.ronnqvist@gmail.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="">Would this also affect the syntax for naming closure arguments? For example, would this (taken from "The Swift Programming Language (Swift 2.2)”):</div><div class=""><ol class="code-lines" style="border: 0px; font-size: 14px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; counter-reset: li 0; line-height: 1.6em; list-style: none; font-family: Helvetica, Arial, sans-serif;"><li style="border-width: 0px 0px 0px 18px; border-left-style: solid; border-left-color: transparent; margin: 0px; outline: 0px; padding: 0px 10px 0px 0px; vertical-align: baseline; text-indent: -13px; white-space: pre-wrap; color: rgb(255, 255, 255); content: ' '; list-style-type: none;" class=""><code class="code-voice" style="border: 0px; font-size: 0.85em; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; font-family: Menlo, monospace; word-wrap: break-word;"><span class="vc" style="border: 0px; font-size: 11.899999618530273px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; color: rgb(63, 110, 116);"> reversed</span> = <span class="vc" style="border: 0px; font-size: 11.899999618530273px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; color: rgb(63, 110, 116);">names</span>.<span class="vc" style="border: 0px; font-size: 11.899999618530273px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; color: rgb(63, 110, 116);">sort</span>( { <span class="vc" style="border: 0px; font-size: 11.899999618530273px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; color: rgb(63, 110, 116);">s1</span>, <span class="vc" style="border: 0px; font-size: 11.899999618530273px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; color: rgb(63, 110, 116);">s2</span> <span class="kt" style="border: 0px; font-size: 11.899999618530273px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; color: rgb(170, 51, 145);">in</span> <span class="kt" style="border: 0px; font-size: 11.899999618530273px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; color: rgb(170, 51, 145);">return</span> <span class="vc" style="border: 0px; font-size: 11.899999618530273px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; color: rgb(63, 110, 116);">s1</span> > <span class="vc" style="border: 0px; font-size: 11.899999618530273px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; color: rgb(63, 110, 116);">s2</span> } )</code></li></ol></div><div class="">have to be written like this:</div><div class=""><ol class="code-lines" style="border: 0px; font-size: 14px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; counter-reset: li 0; line-height: 1.6em; list-style: none; font-family: Helvetica, Arial, sans-serif;"><li style="border-width: 0px 0px 0px 18px; border-left-style: solid; border-left-color: transparent; margin: 0px; outline: 0px; padding: 0px 10px 0px 0px; vertical-align: baseline; text-indent: -13px; white-space: pre-wrap; color: rgb(255, 255, 255); content: ' '; list-style-type: none;" class=""><code class="code-voice" style="border: 0px; font-size: 0.85em; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; font-family: Menlo, monospace; word-wrap: break-word;"><span class="vc" style="border: 0px; font-size: 11.899999618530273px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; color: rgb(63, 110, 116);"> reversed</span> = <span class="vc" style="border: 0px; font-size: 11.899999618530273px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; color: rgb(63, 110, 116);">names</span>.<span class="vc" style="border: 0px; font-size: 11.899999618530273px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; color: rgb(63, 110, 116);">sort</span>( { (<span class="vc" style="border: 0px; font-size: 11.899999618530273px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; color: rgb(63, 110, 116);">s1</span>, <span class="vc" style="border: 0px; font-size: 11.899999618530273px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; color: rgb(63, 110, 116);">s2</span>) <span class="kt" style="border: 0px; font-size: 11.899999618530273px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; color: rgb(170, 51, 145);">in</span> <span class="kt" style="border: 0px; font-size: 11.899999618530273px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; color: rgb(170, 51, 145);">return</span> <span class="vc" style="border: 0px; font-size: 11.899999618530273px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; color: rgb(63, 110, 116);">s1</span> > <span class="vc" style="border: 0px; font-size: 11.899999618530273px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline; color: rgb(63, 110, 116);">s2</span> } )</code></li></ol></div><div class="">or is that a different syntax?</div><div class=""><br class=""></div><div class="">As a developer focused on _writing_ and _reading_ code like this, I don’t see the real benefits of this change. It only feels natural to me that I would be able to omit the parentheses when there is only one type, but that I would need them to group multiple arguments or to label arguments.</div><div class=""><br class=""></div><div class="">That said, I don’t feel strongly about it and the work of transitioning our code would be minimal. If this change provides other engineering benefits that aren’t noticeable on the surface, then I’m positive to the change for those reasons.</div><div class=""><br class=""></div><div class="">- David</div></div></div></blockquote></div><br class=""><div class="">It would not affect the closure syntax. To paraphrase Chris:</div><div class=""><p style="color: rgb(17, 17, 17); font-family: 'Helvetica Neue', Helvetica, Arial, Verdana, sans-serif; word-wrap: break-word; font-size: 1.1429em; line-height: 1.3125em; margin: 1.3125em 0px;" class="">No. Swift’s syntactic shortcuts in its <span class="searchResult" style="background-color: rgba(255, 252, 141, 0.701961); border-top-left-radius: 6px; border-top-right-radius: 6px; border-bottom-right-radius: 6px; border-bottom-left-radius: 6px; color: rgb(34, 34, 34) !important; background-position: initial initial; background-repeat: initial initial;">closure</span> parameter lists benefit simple functional algorithms. Few people would choose to write fully specified long-form declarations when, for example, reverse-sorting an array of integers:</p><pre style="color: rgb(17, 17, 17); font-size: 16px;" class=""><code class="swift coffeescript hljs" style="display: block; padding: 0.5em; color: rgb(51, 51, 51); background-color: rgb(248, 248, 248); background-position: initial initial; background-repeat: initial initial;">y = x.sorted { <span class="hljs-function"><span class="hljs-params" style="color: rgb(153, 0, 0); font-weight: bold;">(lhs : Int, rhs : Int)</span> -></span> Bool <span class="hljs-keyword" style="font-weight: bold;">in</span> rhs < lhs }</code></pre><p style="color: rgb(17, 17, 17); font-family: 'Helvetica Neue', Helvetica, Arial, Verdana, sans-serif; word-wrap: break-word; font-size: 1.1429em; line-height: 1.3125em; margin: 1.3125em 0px;" class="">Compare the long form with this simpler form:</p><pre style="color: rgb(17, 17, 17); font-size: 16px;" class=""><code class="swift actionscript hljs" style="display: block; padding: 0.5em; color: rgb(51, 51, 51); background-color: rgb(248, 248, 248); background-position: initial initial; background-repeat: initial initial;">y = x.sorted { lhs, rhs <span class="hljs-keyword" style="font-weight: bold;">in</span> rhs < lhs }</code></pre><p style="color: rgb(17, 17, 17); font-family: 'Helvetica Neue', Helvetica, Arial, Verdana, sans-serif; word-wrap: break-word; font-size: 1.1429em; line-height: 1.3125em; margin: 1.3125em 0px;" class="">You can use the even shorter form of <code class="">{ $1 < $0 }</code>. </p><p style="color: rgb(17, 17, 17); font-family: 'Helvetica Neue', Helvetica, Arial, Verdana, sans-serif; word-wrap: break-word; font-size: 1.1429em; line-height: 1.3125em; margin: 1.3125em 0px;" class=""><span class="searchResult" style="font-size: 1.1429em; background-color: rgba(255, 252, 141, 0.701961); border-top-left-radius: 6px; border-top-right-radius: 6px; border-bottom-right-radius: 6px; border-bottom-left-radius: 6px; color: rgb(34, 34, 34) !important;">Closure</span><span style="font-size: 1.1429em;" class="">s offer a structurally distinct class of syntactic sugar:</span><span style="font-size: 1.1429em;" class=""> </span></p><ul style="color: rgb(17, 17, 17); font-family: 'Helvetica Neue', Helvetica, Arial, Verdana, sans-serif; font-size: 16px;" class=""><li style="font-size: 18px;" class="">You may elide parentheses (even with multiple arguments)</li><li style="font-size: 18px;" class="">You may omit the return type</li><li style="font-size: 18px;" class="">You may omit types</li><li style="font-size: 18px;" class="">You may omit the parameter list in its entirety</li></ul><p style="color: rgb(17, 17, 17); font-family: 'Helvetica Neue', Helvetica, Arial, Verdana, sans-serif; word-wrap: break-word; font-size: 1.1429em; line-height: 1.3125em; margin: 1.3125em 0px;" class="">Short of a complete rethink of <span class="searchResult" style="background-color: rgba(255, 252, 141, 0.701961); border-top-left-radius: 6px; border-top-right-radius: 6px; border-bottom-right-radius: 6px; border-bottom-left-radius: 6px; color: rgb(34, 34, 34) !important; background-position: initial initial; background-repeat: initial initial;">closure</span> syntax, requiring parentheses there would not improve the language in any measurable way.</p></div></body></html>