https://issues.dlang.org/show_bug.cgi?id=21841

          Issue ID: 21841
           Summary: std.format: grouping produces strange result with zero
                    precision and %e
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: bugzilla@bernis-buecher.de

assert("%0.0,e"(0.0) == "0e+00");

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