https://issues.dlang.org/show_bug.cgi?id=21820

          Issue ID: 21820
           Summary: std.format: formatting zero should never lead to empty
                    string
           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(format!"%#.0o"(0) == "0");

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