<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="">Hi Erica,<div class=""><br class=""></div><div class="">I disagree that trailing commas can lead to unsafe code. What if I'm coding the initialization of an array or dictionary, I'm interrupted, and I forget to go back and finish it. There's a trailing command left dangling in the initialization code. Today, the compiler warns me, I go back and have an "aha moment', fix the code, and everyone is happy. If we allow trailing commands, the compiler never warns me, I'm left with unfinished initialization code, it builds anyways, and I have a bad day.</div><div class=""><br class=""></div><div class="">Cheers,</div><div class="">-Patrick</div><div class=""><br class=""><div><blockquote type="cite" class=""><div class="">On Mar 10, 2016, at 3:27 PM, Erica Sadun 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=""><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=""><blockquote type="cite" class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class=""><div class=""><blockquote type="cite" class=""><div class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class=""><blockquote type="cite" class=""><div class="">On 10 Mar 2016, at 17:28, Radosław Pietruszewski <<a href="mailto:radexpl@gmail.com" class="">radexpl@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="">Trailing comma is not nonsensical, there is a specific purpose in allowing it (unlike your examples), and there’s precedent in Swift already.</div><div class=""><br class=""></div></div></div></blockquote></div></div></div></blockquote></div></div></div></blockquote><br class=""></div><div class="">Trailing commas enable easier re-ordering of arguments, simplify growing or compacting argument lists, and do no harm.</div><div class=""><br class=""></div><div class="">Their use in arrays and dictionaries are conventional enough that experienced programmers will not be surprised by their</div><div class="">presence. No one will force their use and one's internal style guide (and linters) can direct whether any individual group</div><div class="">adopts or ignores the addition.</div><div class=""><br class=""></div><div class="">For those of us who prefer trailing commas, it will be both a convenience and an asset. For those against, there's no harm</div><div class="">done. I find it unlikely that trailing commas will naturally lead to any unsafe code or produce a net negative effect on the</div><div class="">language or the code-base it supports.</div><div class=""><br class=""></div><div class="">-- Erica</div><div class=""><br class=""></div><br class=""></div>_______________________________________________<br class="">swift-evolution mailing list<br class=""><a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a><br class="">https://lists.swift.org/mailman/listinfo/swift-evolution<br class=""></div></blockquote></div><br class=""></div></body></html>