https://issues.dlang.org/show_bug.cgi?id=23940

          Issue ID: 23940
           Summary: std.getopt does not assert with options that only
                    differ in case with config.caseInsensitive
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: dlang-bugzilla@thecybershadow.net

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