<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">[Proposal:&nbsp;<a href="https://github.com/apple/swift-evolution/blob/master/proposals/0181-package-manager-cpp-language-version.md" class="">https://github.com/apple/swift-evolution/blob/master/proposals/0181-package-manager-cpp-language-version.md</a>]<div class=""><br class=""></div><div class="">I don't feel like I have the perspective for broad comments on the use cases for the proposal, but here are some low-level thoughts:</div><div class=""><br class=""></div><div class=""><pre style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 13.600000381469727px; margin-top: 0px; margin-bottom: 0px; font-stretch: normal; line-height: 1.45; word-wrap: normal; padding: 16px; overflow: auto; background-color: rgb(246, 248, 250); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; word-break: normal; color: rgb(36, 41, 46);" class=""><span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">public</span> <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">enum</span> <span class="pl-en" style="box-sizing: border-box; color: rgb(111, 66, 193);">CLanguageStandard</span> {
    <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">case</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 92, 197);">c89</span>
    <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">case</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 92, 197);">c90</span>
    <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">case</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 92, 197);">iso9899_1990</span>
    <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">case</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 92, 197);">iso9899_199409</span>
    <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">case</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 92, 197);">gnu89</span>
    <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">case</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 92, 197);">gnu90</span>
    <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">case</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 92, 197);">c99</span>
    <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">case</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 92, 197);">iso9899_1999</span>
    <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">case</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 92, 197);">gnu99</span>
    <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">case</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 92, 197);">c11</span>
    <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">case</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 92, 197);">iso9899_2011</span>
    <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">case</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 92, 197);">gnu11</span>
}
</pre></div><div class=""><br class=""></div><div class="">I don't think it's worth having every name and every alias here. c89/gnu89, c99/gnu99, and c11/gnu11 covers all of the variants and is what's used most in practice anyway. (IIRC C89 and C90 have some tiny difference from the second standardization, but Clang ignores this difference anyway.)</div><div class=""><br class=""></div><div class=""><pre style="box-sizing: border-box; font-family: SFMono-Regular, Consolas, 'Liberation Mono', Menlo, Courier, monospace; font-size: 13.600000381469727px; margin-top: 0px; margin-bottom: 0px; font-stretch: normal; line-height: 1.45; word-wrap: normal; padding: 16px; overflow: auto; background-color: rgb(246, 248, 250); border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; word-break: normal; color: rgb(36, 41, 46);" class=""><span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">public</span> <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">enum</span> <span class="pl-en" style="box-sizing: border-box; color: rgb(111, 66, 193);">CXXLanguageStandard</span> {
    <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">case</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 92, 197);">cxx98</span>
    <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">case</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 92, 197);">cxx03</span>
    <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">case</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 92, 197);">gnucxx98</span>
    <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">case</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 92, 197);">gnucxx03</span>
    <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">case</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 92, 197);">cxx11</span>
    <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">case</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 92, 197);">gnucxx11</span>
    <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">case</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 92, 197);">cxx14</span>
    <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">case</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 92, 197);">gnucxx14</span>
    <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">case</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 92, 197);">cxx1z</span>
    <span class="pl-k" style="box-sizing: border-box; color: rgb(215, 58, 73);">case</span> <span class="pl-c1" style="box-sizing: border-box; color: rgb(0, 92, 197);">gnucxx1z</span>
}</pre><div class=""><br class=""></div></div><div class="">Similar thoughts here. I also wonder if "gnucxx98" is redundant, given that it's already in a containing enum called "CXXLanguageStandard" (or "CPPLanguageStandard", or even "CPlusPlusLanguageStandard", depending on how that discussion goes). "gnu98" seems sufficient.</div><div class=""><br class=""></div><div class="">I really don't like saying "cxx1z". Can we just say "cxx17" because it's <i class="">really</i>&nbsp;likely we'll get it this year?</div><div class=""><br class=""></div><div class="">If this were a longer-term issue (say, if there were references to "cxx2a") I'd ask what the plan is for aliases in the future. You'd want "cxx2a" and "cxx21" to eventually compare equal, right? But since this will get subsumed by build settings I think it's okay not to worry about that, or any custom standards a vendor or Clang experimenter might try to add.</div><div class=""><br class=""></div><div class="">Jordan</div></body></html>