<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="" applecontenteditable="true"><br class=""><div><blockquote type="cite" class=""><div class="">On Mar 21, 2017, at 15:26, Xiaodi Wu via swift-evolution &lt;<a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a>&gt; wrote:</div><br class="Apple-interchange-newline"><div class=""><div style="font-family: Helvetica; font-size: 12px; 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;" class="">The kicker is, _it also doesn't work_. Try, for instance:</div><div style="font-family: Helvetica; font-size: 12px; 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;" class=""><br class=""></div><div style="font-family: Helvetica; font-size: 12px; 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;" class="">```</div><div style="font-family: Helvetica; font-size: 12px; 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;" class=""><div style="margin: 0px; font-size: 11px; line-height: normal; font-family: menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures; color: rgb(186, 45, 162);" class="">struct</span><span style="font-variant-ligatures: no-common-ligatures;" class=""><span class="Apple-converted-space">&nbsp;</span>Foo {</span></div><div style="margin: 0px; font-size: 11px; line-height: normal; font-family: menlo; color: rgb(186, 45, 162);" class=""><span style="font-variant-ligatures: no-common-ligatures;" class="">&nbsp;<span class="Apple-converted-space">&nbsp;</span></span><span style="font-variant-ligatures: no-common-ligatures;" class="">private</span><span style="font-variant-ligatures: no-common-ligatures;" class=""><span class="Apple-converted-space">&nbsp;</span></span><span style="font-variant-ligatures: no-common-ligatures;" class="">var</span><span style="font-variant-ligatures: no-common-ligatures;" class=""><span class="Apple-converted-space">&nbsp;</span>bar:<span class="Apple-converted-space">&nbsp;</span></span><span style="font-variant-ligatures: no-common-ligatures; color: rgb(112, 61, 170);" class="">Int</span><span style="font-variant-ligatures: no-common-ligatures;" class=""><span class="Apple-converted-space">&nbsp;</span>{<span class="Apple-converted-space">&nbsp;</span></span><span style="font-variant-ligatures: no-common-ligatures;" class="">return</span><span style="font-variant-ligatures: no-common-ligatures;" class=""><span class="Apple-converted-space">&nbsp;</span></span><span style="font-variant-ligatures: no-common-ligatures; color: rgb(39, 42, 216);" class="">42</span><span style="font-variant-ligatures: no-common-ligatures;" class=""><span class="Apple-converted-space">&nbsp;</span>}</span></div><div style="margin: 0px; font-size: 11px; line-height: normal; font-family: menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures;" class="">}</span></div><div style="margin: 0px; font-size: 11px; line-height: normal; font-family: menlo; min-height: 13px;" class=""><span style="font-variant-ligatures: no-common-ligatures;" class=""></span><br class=""></div><div style="margin: 0px; font-size: 11px; line-height: normal; font-family: menlo; color: rgb(186, 45, 162);" class=""><span style="font-variant-ligatures: no-common-ligatures;" class="">extension</span><span style="font-variant-ligatures: no-common-ligatures;" class=""><span class="Apple-converted-space">&nbsp;</span></span><span style="font-variant-ligatures: no-common-ligatures; color: rgb(79, 129, 135);" class="">Foo</span><span style="font-variant-ligatures: no-common-ligatures;" class=""><span class="Apple-converted-space">&nbsp;</span>{</span></div><div style="margin: 0px; font-size: 11px; line-height: normal; font-family: menlo; color: rgb(186, 45, 162);" class=""><span style="font-variant-ligatures: no-common-ligatures;" class="">&nbsp;<span class="Apple-converted-space">&nbsp;</span></span><span style="font-variant-ligatures: no-common-ligatures;" class="">private</span><span style="font-variant-ligatures: no-common-ligatures;" class=""><span class="Apple-converted-space">&nbsp;</span></span><span style="font-variant-ligatures: no-common-ligatures;" class="">var</span><span style="font-variant-ligatures: no-common-ligatures;" class=""><span class="Apple-converted-space">&nbsp;</span>bar:<span class="Apple-converted-space">&nbsp;</span></span><span style="font-variant-ligatures: no-common-ligatures; color: rgb(112, 61, 170);" class="">Int</span><span style="font-variant-ligatures: no-common-ligatures;" class=""><span class="Apple-converted-space">&nbsp;</span>{<span class="Apple-converted-space">&nbsp;</span></span><span style="font-variant-ligatures: no-common-ligatures;" class="">return</span><span style="font-variant-ligatures: no-common-ligatures;" class=""><span class="Apple-converted-space">&nbsp;</span></span><span style="font-variant-ligatures: no-common-ligatures; color: rgb(39, 42, 216);" class="">43</span><span style="font-variant-ligatures: no-common-ligatures;" class=""><span class="Apple-converted-space">&nbsp;</span>}</span></div><div style="margin: 0px; font-size: 11px; line-height: normal; font-family: menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures;" class="">}</span></div></div><div style="font-family: Helvetica; font-size: 12px; 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;" class="">```</div><div style="font-family: Helvetica; font-size: 12px; 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;" class=""><br class=""></div><div style="font-family: Helvetica; font-size: 12px; 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;" class="">The code above should compile and does not. If I understood correctly the explanation from a core team member on this list, it's unclear if it can be made to work without changing how mangling works, which I believe impacts ABI and is not trivial at all. Thus, (a) even proponents of new `private` disagree on one of two key goals stated for new `private`; (b) that goal was never accomplished, and making it work is not trivial; (c) no one even complained about it, suggesting that it was a low-yield goal in the first place.</div></div></blockquote><div><br class=""></div><div>Without commenting on anything else, it is considered a bug that this does not work under SE-0025, and it <i class="">has</i>&nbsp;been&nbsp;<a href="https://bugs.swift.org/browse/SR-2634" class="">complained about</a>&nbsp;(though not vigorously, since the workaround is trivial), and fixing it would not be an ABI-breaking change (because private functions are not part of a module's ABI).</div><div><br class=""></div><div>Jordan</div></div></body></html>