Re: [boost] [spirit] How to detect Spirit.Qi expressions?

Subject: Re: [boost] [spirit] How to detect Spirit.Qi expressions?
From: Andrey Semashev (andrey.semashev_at_[hidden])
Date: 2014-03-30 09:25:52

On Sunday 30 March 2014 21:15:29 TONGARI J wrote:
> 2014-03-30 20:52 GMT+08:00 Andrey Semashev <andrey.semashev_at_[hidden]>:
> > Hi,
> > 
> > Is there a way to detect at compile time that a certain type is a
> > Boost.Spirit.Qi parser? That includes template expressions and grammars.
> > Basically, I want to detect if qi::parse(b, e, expr) would be a sensible
> > thing
> > to do.
> > 
> > I tried this:
> >   boost::is_same<
> >   
> >     typename proto::domain_of< ExpressionT >::type,
> >     spirit::qi::domain
> > 
> > But domain_of returns default_domain for Boost.Spirit.Qi template
> > expressions.
> 
> Try this:
> boost::spirit::traits::matches< Domain, Expr >

Thanks, this seems to work. Is it documented anywhere? Can I use it without 
safely?