[Qemu-devel] Re: [PATCH 0/6]: QMP: Fix issues in parser/lexer

[Luiz Capitulino]

On Thu, 20 May 2010 10:52:58 -0500
Anthony Liguori <address@hidden> wrote:

> On 05/20/2010 10:18 AM, Paolo Bonzini wrote:
> > On 05/19/2010 11:43 PM, Anthony Liguori wrote:
> >>
> >>> 4. Lexer expects a 'terminal' char to process a token
> >>>
> >>>     Which means clients must send a sort of end of line char, so 
> >>> that we
> >>>     process their input.
> >>>
> >>>     Maybe I'm missing something here, but I thought that the whole
> >>>     point of writing our own parser was to avoid this.
> >>
> >> If the lexer gets:
> >>
> >> "abc"
> >>
> >> It has no way of knowing if that's a token or if we're going to get:
> >>
> >> "abcd"
> >
> > Only } and ] are valid characters at the end of a JSON object, and 
> > neither requires lookahead.
> 
> Having look ahead operate differently for different states really 
> complicates the lexer.  I don't see this as a big problem in practice.

 Would be a nice feature, but it's fine for me too and we'll have to
note that in the QMP's spec.