<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 Jun 7, 2016, at 11:11, L Mihalkovic 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=""><div style="margin: 0px; line-height: normal; font-family: Menlo; min-height: 14px;" class="">T1 =======</div><div style="margin: 0px; line-height: normal; font-family: Menlo; color: rgb(187, 44, 162);" class=""><span style="font-variant-ligatures: no-common-ligatures;" class="">import</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> Lib1</span></div><div style="margin: 0px; line-height: normal; font-family: Menlo; color: rgb(187, 44, 162);" class=""><span style="font-variant-ligatures: no-common-ligatures;" class="">var</span><span style="color: rgb(49, 89, 93);" class=""> str = </span><span style="color: rgb(49, 89, 93);" class="">func2</span><span style="color: rgb(49, 89, 93);" class="">()<span class="Apple-tab-span" style="white-space:pre"> </span>// lib1</span></div><div style="margin: 0px; line-height: normal; font-family: Menlo; color: rgb(187, 44, 162);" class=""><span style="font-variant-ligatures: no-common-ligatures; color: #31595d" class=""><div style="margin: 0px; line-height: normal; color: rgb(187, 44, 162);" class=""><span style="font-variant-ligatures: no-common-ligatures;" class=""><br class=""></span></div><div style="margin: 0px; line-height: normal; min-height: 14px;" class="">T2 =======</div><div style="margin: 0px; line-height: normal; color: rgb(187, 44, 162);" class=""><span style="font-variant-ligatures: no-common-ligatures;" class="">import</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> Lib1</span></div><div style="margin: 0px; line-height: normal; color: rgb(187, 44, 162);" class=""><span style="font-variant-ligatures: no-common-ligatures;" class="">import</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> </span><span style="font-variant-ligatures: no-common-ligatures;" class="">func</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> Lib2.</span><span style="font-variant-ligatures: no-common-ligatures; color: rgb(49, 89, 93);" class="">func2</span></div><div style="margin: 0px; line-height: normal; color: rgb(187, 44, 162);" class=""><span style="font-variant-ligatures: no-common-ligatures; color: rgb(49, 89, 93);" class=""><span style="font-variant-ligatures: no-common-ligatures; color: rgb(187, 44, 162);" class="">var</span> str = func2()<span class="Apple-tab-span" style="white-space:pre"> </span>// lib2</span></div><div class=""><span style="font-variant-ligatures: no-common-ligatures; color: rgb(49, 89, 93);" class=""><br class=""></span></div></span></div><div style="margin: 0px; line-height: normal; min-height: 14px;" class=""><font face="Menlo" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""></span></font><div style="font-family: Menlo; margin: 0px; line-height: normal; min-height: 14px;" class="">T3 =======</div><div style="font-family: Menlo;" class=""><div style="margin: 0px; line-height: normal; color: rgb(187, 44, 162);" class=""><span style="font-variant-ligatures: no-common-ligatures;" class="">import</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> Lib1</span></div><div style="margin: 0px; line-height: normal; color: rgb(187, 44, 162);" class=""><span style="font-variant-ligatures: no-common-ligatures;" class="">import</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> </span><span style="font-variant-ligatures: no-common-ligatures;" class="">func</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> Lib2.</span><span style="font-variant-ligatures: no-common-ligatures; color: rgb(49, 89, 93);" class="">func2</span></div><div style="margin: 0px; line-height: normal; color: rgb(187, 44, 162);" class=""><span style="font-variant-ligatures: no-common-ligatures; color: rgb(49, 89, 93);" class=""><span style="font-variant-ligatures: no-common-ligatures; color: rgb(187, 44, 162);" class="">var</span> str = “str”.allCaps()<span class="Apple-tab-span" style="white-space:pre"> </span>// ERROR : ambiguous name</span></div></div><div style="margin: 0px; line-height: normal;" class=""><font color="#31595d" class=""><font face="Menlo" class=""><br class=""></font></font></div><div style="margin: 0px; line-height: normal;" class=""><br class=""></div></div></div><div style="margin: 0px; line-height: normal; font-family: Menlo; min-height: 14px;" class="">Lib1 ===========</div><div style="margin: 0px; line-height: normal; font-family: Menlo; min-height: 14px;" class=""><div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures; color: #bb2ca2" class="">public</span><span style="font-variant-ligatures: no-common-ligatures" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #bb2ca2" class="">func</span><span style="font-variant-ligatures: no-common-ligatures" class=""> func2() -> </span><span style="font-variant-ligatures: no-common-ligatures; color: #703daa" class="">String</span><span style="font-variant-ligatures: no-common-ligatures" class=""> {</span></div><div style="margin: 0px; line-height: normal; color: rgb(187, 44, 162);" class=""><span style="font-variant-ligatures: no-common-ligatures;" class=""> </span><span style="font-variant-ligatures: no-common-ligatures" class="">return</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #d12f1b" class="">"lib1"</span></div><div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">}</span></div><div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">// only during T3</span></div><div class=""><span style="font-variant-ligatures: no-common-ligatures" class=""><div style="margin: 0px; line-height: normal; color: rgb(187, 44, 162);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">public</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> </span><span style="font-variant-ligatures: no-common-ligatures" class="">extension</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #703daa" class="">String</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> {</span></div><div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #bb2ca2" class="">public</span><span style="font-variant-ligatures: no-common-ligatures" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #bb2ca2" class="">func</span><span style="font-variant-ligatures: no-common-ligatures" class=""> allCaps() -> </span><span style="font-variant-ligatures: no-common-ligatures; color: #703daa" class="">String</span><span style="font-variant-ligatures: no-common-ligatures" class=""> {</span></div><div style="margin: 0px; line-height: normal; color: rgb(112, 61, 170);" class=""><span style="font-variant-ligatures: no-common-ligatures;" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #bb2ca2" class="">return</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #d12f1b" class="">“lib1_</span><span style="font-variant-ligatures: no-common-ligatures; color: #d12f1b" class="">"</span></div><div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> }</span></div><div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">}</span></div><div class=""><span style="font-variant-ligatures: no-common-ligatures" class=""><br class=""></span></div></span></div></div><div class=""><div style="margin: 0px; line-height: normal; font-family: Menlo; min-height: 14px;" class=""><div style="margin: 0px; line-height: normal; min-height: 14px;" class="">Lib2 ===========</div><div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures; color: #bb2ca2" class="">public</span><span style="font-variant-ligatures: no-common-ligatures" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #bb2ca2" class="">func</span><span style="font-variant-ligatures: no-common-ligatures" class=""> func2() -> </span><span style="font-variant-ligatures: no-common-ligatures; color: #703daa" class="">String</span><span style="font-variant-ligatures: no-common-ligatures" class=""> {</span></div><div style="margin: 0px; line-height: normal; color: rgb(187, 44, 162);" class=""><span style="font-variant-ligatures: no-common-ligatures;" class=""> </span><span style="font-variant-ligatures: no-common-ligatures" class="">return</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #d12f1b" class="">"lib2"</span></div><div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">}</span></div><div class=""><span style="font-variant-ligatures: no-common-ligatures" class=""><div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures;" class="">// only during T3</span></div><div class=""><span style="font-variant-ligatures: no-common-ligatures;" class=""></span></div><div style="margin: 0px; line-height: normal; color: rgb(187, 44, 162);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">public</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> </span><span style="font-variant-ligatures: no-common-ligatures" class="">extension</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #703daa" class="">String</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> {</span></div><div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #bb2ca2" class="">public</span><span style="font-variant-ligatures: no-common-ligatures" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #bb2ca2" class="">func</span><span style="font-variant-ligatures: no-common-ligatures" class=""> allCaps() -> </span><span style="font-variant-ligatures: no-common-ligatures; color: #703daa" class="">String</span><span style="font-variant-ligatures: no-common-ligatures" class=""> {</span></div><div style="margin: 0px; line-height: normal; color: rgb(112, 61, 170);" class=""><span style="font-variant-ligatures: no-common-ligatures;" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #bb2ca2" class="">return</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #d12f1b" class="">"lib2_</span><span style="font-variant-ligatures: no-common-ligatures; color: #d12f1b" class="">"</span></div><div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> }</span></div><div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">}</span></div><div class=""><span style="font-variant-ligatures: no-common-ligatures" class=""><br class=""></span></div></span></div></div></div><div class=""><br class=""></div><div class="">T3 shows how differently extensions are treated from all other exportable/importable artifacts: <span style="color: rgb(49, 89, 93); font-family: Menlo;" class="">extensions are NOT sensitive to the scope of imports. they are fully loaded as soon as the loader detects that the module is referenced (they come from their own table inside the module binary).</span></div></div></div></blockquote><br class=""></div><div>I personally consider this a longstanding bug, and would like extension member visibility to follow the same rules as top-level visibility. I don’t think that’s trivial to change, though; the lookup paths are very very different.</div><div><br class=""></div><div>Jordan</div><br class=""></body></html>