https://issues.dlang.org/show_bug.cgi?id=23527

          Issue ID: 23527
           Summary: More detailed error messages from is(...) and
                    _traits(compiles)
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: john.michael.hall@gmail.com

From https://forum.dlang.org/post/ooraoriyrftjrpoygtnk@forum.dlang.org

Returning error messages from failed `is(...)` and `__traits(compiles)` checks
instead of just `false`

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