https://issues.dlang.org/show_bug.cgi?id=24472

          Issue ID: 24472
           Summary: __traits(fullyQualifedName) is undocumented in spec
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: normal
          Priority: P1
         Component: dlang.org
          Assignee: nobody@puremagic.com
          Reporter: nick@geany.org

Added in issue 16495.
The std.traits docs should also mention to prefer this:
https://dlang.org/phobos/std_traits.html#fullyQualifiedName

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