[clang-tools-extra] [clang-doc] Add a Mustache Markdown generator (PR #177221)

[Paul Kirth via cfe-commits]

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@@ -358,7 +359,8 @@ serializeCommonAttributes(const Info &I, json::Object &Obj,
                           const std::optional<StringRef> RepositoryUrl,
                           const std::optional<StringRef> RepositoryLinePrefix) {
   insertNonEmpty("Name", I.Name, Obj);
-  Obj["USR"] = toHex(toStringRef(I.USR));
+  if (!(I.USR == GlobalNamespaceID))
+    Obj["USR"] = toHex(toStringRef(I.USR));
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ilovepi wrote:

What's the point of this specialization? Can't any consumer just check the USR against the known sentinel value? I'd think this would make everything else more expensive, since USR isn't guaranteed to exist in the output, and now the schema is customized on if its present or not...

https://github.com/llvm/llvm-project/pull/177221