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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hi Yitzhak<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thank you for pointing me in the right direction. The trick was to call getAsCXXRecordDecl on the type object first and then cast it to ClassTemplateSpecializationDecl .<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>clang::CXXRecordDecl * record = type->getAsCXXRecordDecl(); <o:p></o:p></p><p class=MsoNormal>if (const auto * templateDecl = llvm::dyn_cast<ClassTemplateSpecializationDecl>(record))<o:p></o:p></p><p class=MsoNormal>{<o:p></o:p></p><p class=MsoNormal> const TemplateArgumentList & argList = templateDecl->getTemplateArgs();<o:p></o:p></p><p class=MsoNormal> for (uint i = 0; i < argList.size(); i++)<o:p></o:p></p><p class=MsoNormal> {<o:p></o:p></p><p class=MsoNormal> res.AddTemplateArg(ToSimpleAst(argList.get(i).getAsType()));<o:p></o:p></p><p class=MsoNormal> }<o:p></o:p></p><p class=MsoNormal>}<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><b>From:</b> Yitzhak Mandelbaum <yitzhakm@google.com> <br><b>Sent:</b> Monday, December 21, 2020 16:41<br><b>To:</b> Massa, Gert (DI SW STS R&D SIM ARCH) <gert.massa@siemens.com><br><b>Cc:</b> cfe-dev@lists.llvm.org<br><b>Subject:</b> Re: [cfe-dev] Getting template arguments from a clang::Type object<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal><span style='font-family:"Arial",sans-serif'>You probably want to look at `ClassTemplatesSpecializationDecl`. If you're doing this in the context of AST matchers, then something like the following is probably what you want:<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial",sans-serif'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial",sans-serif'>```<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial",sans-serif'>AST_MATCHER_P(clang::TypeLoc, templateSpecializationTypeLoc,<br> clang::ast_matchers::TypeLocMatcher, InnerMatcher) {<br> auto L = Node.getAs<clang::TemplateSpecializationTypeLoc>();<br> if (L.isNull()) return false;<br> return InnerMatcher.matches(L, Finder, Builder);<br>}<br><br>AST_MATCHER_P(<br> clang::TypeLoc, hasAnyTemplateArgumentLoc,<br> clang::ast_matchers::internal::Matcher<clang::TemplateArgumentLoc>,<br> InnerMatcher) {<br> auto L = Node.getAs<clang::TemplateSpecializationTypeLoc>();<br> if (L.isNull()) return false;<br> for (unsigned Index = 0, N = L.getNumArgs(); Index < N; ++Index) {<br> clang::ast_matchers::internal::BoundNodesTreeBuilder Result(*Builder);<br> if (InnerMatcher.matches(L.getArgLoc(Index), Finder, &Result)) {<br> *Builder = std::move(Result);<br> return true;<br> }<br> }<br> return false;<br>}<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial",sans-serif'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial",sans-serif'>AST_MATCHER_P(clang::TemplateArgumentLoc, refersToTypeLoc,<br> clang::ast_matchers::internal::Matcher<clang::TypeLoc>,<br> InnerMatcher) {<br> return Node.getArgument().getKind() == clang::TemplateArgument::Type &&<br> InnerMatcher.matches(Node.getTypeSourceInfo()->getTypeLoc(), Finder,<br> Builder);<br>}<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial",sans-serif'>```<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial",sans-serif'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial",sans-serif'>These could be used in a matcher, for example, to identify a type which is a template instantiation with any argument that refers to some type of interest (here, identified by `inner_matcher`).<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial",sans-serif'>```<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial",sans-serif'>auto template_instantiation =<br> templateSpecializationTypeLoc(hasAnyTemplateArgumentLoc(<br> templateArgumentLoc(refersToTypeLoc(inner_matcher))));<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial",sans-serif'>```<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial",sans-serif'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Arial",sans-serif'>As for AST guides, I don't know of any good ones, unfortunately. My first place to look is clang-query (especially in <a href="http://godbolt.org">godbolt.org</a>) -- I enter a code snippet and see what the resulting AST looks like. To see the AST for types, try using something like this in <a href="http://godbolt.org">godbolt.org</a>: <a href="https://godbolt.org/z/bTaoTE" target="_blank"><span style='font-size:10.5pt;color:#1A73E8'>https://godbolt.org/z/bTaoTE</span></a>. (Kudos to Richard Smith for this one...).<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On Mon, Dec 21, 2020 at 9:04 AM Massa, Gert via cfe-dev <<a href="mailto:cfe-dev@lists.llvm.org">cfe-dev@lists.llvm.org</a>> wrote:<o:p></o:p></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in'><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Hi All,<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Can anyone tell me how to get the template arguments from a clang::Type object? For example, if I have clang::Type for “std::vector<int>”, how do I get to this “int” type? <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>When looking at the API reference I’m getting a bit lost with all the terminology I’m not yet familiar with, any good resources to that explains the terminology? Especially how templates are represented is still unclear to me.<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Thanks in advanced for your help and a huge thanks to all the LLVM and clang contributes!<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>With Kind Regards,<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Gert Massa<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p></div></div><p class=MsoNormal>_______________________________________________<br>cfe-dev mailing list<br><a href="mailto:cfe-dev@lists.llvm.org" target="_blank">cfe-dev@lists.llvm.org</a><br><a href="https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-dev" target="_blank">https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-dev</a><o:p></o:p></p></blockquote></div></div></body></html>