https://issues.dlang.org/show_bug.cgi?id=19124

          Issue ID: 19124
           Summary: Investigate using RYU to convert floats to strings
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: b2.temp@gmx.com

Relying in the c standard library to do that is sometimes an issue. It's been encountered several time, e.g in std.json because snn.lib give different results that the gnu c library. It would also allow to get it to!string, format working at CTFE for float and double.

Reference : https://github.com/ulfjack/ryu

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