https://issues.dlang.org/show_bug.cgi?id=14399

          Issue ID: 14399
           Summary: std.json cannot parse its own output for nan
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: normal
          Priority: P1
         Component: Phobos
          Assignee: nobody@puremagic.com
          Reporter: murphyslaw480@gmail.com

JSONValue(["val" : float.nan]).toString yeilds `{"val":nan}`.
'nan' is not wrapped in quotes.

However, if you call parseJSON on this string, it fails:
"Found 'a' when expecting 'u'" (I guess its trying to parse 'null').

I would expect std.json to be able to parse the strings it outputs.

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