Re: [boost] interest in 'tagged variant'? Useful in non-string spirit parsing.

From: Joel de Guzman (joel_at_[hidden])
Date: 2007-12-17 17:29:25

Larry Evans wrote:

> A new version has been uploaded to vault which uses fusion::pair.
> To facilitate this, a new fusion/support/intkey_val_pair_map.hpp
> file containing like-named template was created.
> What's interesting about this is that it seems that if
> instead of boost::variant, fusion::map were used with the
> intkey_val_pair_map as arg(maybe mpl::unpacked), then you'd
> have a tuple with possibly "named"(or enumed) instead of
> less meaningful unsigned indexes (i.e. args to get<>).
> OTOH, if, instead of fusion::pair, mpl::pair were used, and then
> the intkey_...map passed to mpl::map, then you have the mpl
> map with "named" indices.
> 
> I'm looking for a generalization that can simplify the coding
> of all the classes by defining a minimum number of templates
> that can be combined to get the most general results.
> Does that make sense?

Hi Larry, Pardon the delay in replying. Yeah, this makes
perfect sense. Are there docs yet? Would you be interested in
having it hosted in spirit2/support ?

Regards,
-- 
Joel de Guzman
http://www.boost-consulting.com
http://spirit.sf.net