https://issues.dlang.org/show_bug.cgi?id=20146

          Issue ID: 20146
           Summary: Allow casting from std.bigint.BigInt to built-in
                    floating point types
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: n8sh.secondary@hotmail.com

Currently only casting to integer types is supported.

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