non-standard json output

[Brian Schott]

On Tuesday, 4 June 2013 at 20:59:55 UTC, Anthony Goins wrote:
> Is this a bug?
>
> "file" : "/home/anthony/projects/dcomposer/src/printui.d",
>
> A line from DMD 2.063 json output.
>
> "file" : "\/usr\/include\/d\/gsv\/SourceBuffer.d",
>
> A line from an older DMD version. Forward slashes escaped 
> according to json standard.
>
> Hesitant to file a bug report because by the time I see 
> something it's probably already well known and fixed.

Where does the standard say that forward slashes have to be 
escaped? It shows in the syntax diagram that you CAN escape it, 
but there is no requirement to do so as it is a unicode character 
other than '"' or '\'