[Boost-users] [Proto] Building a mpl::vector from an expression

Subject: [Boost-users] [Proto] Building a mpl::vector from an expression
From: christophe henry (henry_christophe_at_[hidden])
Date: 2009-08-18 15:32:53

Hi,

 

I am trying to build a mpl::vector from an expression like

(string(),ClassA(),ClassB())

To get a mpl::vector<string,ClassA,ClassB>

 

With string, ClassA and ClassB being not enough under control to protoify them with a proto::extends.

 

I naively tried the following grammar

 

struct BuildFlags

: proto::or_<

proto::when <

proto::terminal<proto::_>,

boost::mpl::vector<proto::_child>()

>,

proto::when <

proto::comma<BuildFlags,BuildFlags >,

boost::mpl::push_back<

BuildFlags(proto::_left),proto::_right>() 

>

>

{};

 

Or some typeof variants of it, with no more success and I start wondering if I got on a rocky way leading me to unavoidable doom.

Is there a way to do this or I should give up the idea?

 

Thanks,

 

Christophe

_________________________________________________________________
Share your memories online with anyone you want.
http://www.microsoft.com/middleeast/windows/windowslive/products/photos-share.aspx?tab=1