On Fri, 6 Feb 2004, Angus Leeming wrote:
> Andre Poenitz wrote:
>
> > On Thu, Feb 05, 2004 at 05:36:03PM +0000, Angus Leeming wrote:
> >> I've been using Boost.Spirit a lot at work recently and so have
> >> become quite comfortable with Spirit's phoenix library (a better
> >> lambda?)
> >
> > I've been using plain old for loops for ages and have become quite
> > comfortable with them...
> >
> > Andre'
>
> Here's an example of a simple parser written using Boost Spirit to
> read the data set below and assign the values using phoenix's lambda
> facility. It's extremely understandable IMO and has all the error
Um... I don't understand it... OTOH I've never used Boost Spirit,
but that means it's not obvious if you're unfamiliar with that.
Could you give a link for Boost Spirit? (and maybe a few comments?)
This is the data set of course:
> CONCENTRATION
>
> NNODES 5
>
> 1 5.5
> 2 6.5
> 3 5.0
> 4 4.5
> 5 4.0
>
And here's a part of the parser. But I don't understand it, guess I don't
know what for instance 'var' or 'self' mean/do... Is 'expression' a
variable? (what type?)
> vector<double> & field = ...;
> string & field_name = ...;
>
> expression =
> f_str_p(var(self.field_name)) >>
> str_p("NNODES") >>
>
> uint_p[resize(var(field), arg1)] >>
>
> for_p(var(index) = 1,
> var(index) <= size(var(field)),
> var(index)++)
> [
> limit_d(cref(index), cref(index))[uint_p] >>
> real_p[var(field)[var(index)-1] = arg1]
> ];
/Christian
--
Christian Ridderström http://www.md.kth.se/~chr
