[Qemu-devel] Re: [PATCH 2/6] json-lexer: Handle missing escapes

[Luiz Capitulino]

On Thu, 20 May 2010 13:52:08 -0500
Anthony Liguori <address@hidden> wrote:

> On 05/20/2010 01:47 PM, Luiz Capitulino wrote:
> > On Thu, 20 May 2010 11:55:00 -0500
> > Anthony Liguori<address@hidden>  wrote:
> >
> >    
> >> On 05/20/2010 11:27 AM, Luiz Capitulino wrote:
> >>      
> >>> On Thu, 20 May 2010 10:50:41 -0500
> >>> Anthony Liguori<address@hidden>   wrote:
> >>>
> >>>
> >>>        
> >>>> On 05/20/2010 10:16 AM, Paolo Bonzini wrote:
> >>>>
> >>>>          
> >>>>> On 05/20/2010 03:44 PM, Luiz Capitulino wrote:
> >>>>>
> >>>>>            
> >>>>>>     I think there's another issue in the handling of strings.
> >>>>>>
> >>>>>>     The spec says that valid unescaped chars are in the following 
> >>>>>> range:
> >>>>>>
> >>>>>>        unescaped = %x20-21 / %x23-5B / %x5D-10FFFF
> >>>>>>
> >>>>>>              
> >>>> That's a spec bug IMHO.  Tab is %x09.  Surely you can include tabs in
> >>>> strings.  Any parser that didn't accept that would be broken.
> >>>>
> >>>>          
> >>>    Honestly, I had the impression this should be encoded as: %x5C %x74, 
> >>> but
> >>> if you're right, wouldn't this be true for other sequences as well?
> >>>
> >>>        
> >> I don't think most reasonable clients are going to quote tabs as '\t'.
> >>      
> >   That would be a bug, wouldn't it?
> >    
> 
> Tabs are valid in JavaScript strings and I don't think it's reasonable 
> to expect that a valid JavaScript string is not a valid JSON string.

 IMO, we should do what the spec says and what bug free clients expect,
what we consider reasonable or unreasonable is a different matter.

 I would be with you if the spec was proved wrong, specially if reference
implementations out there didn't follow it either, but everything I found
so far shows this is not the case.

 Another example:

   http://www.json.org/json2.js

 Search for 'character substitutions'.