Re: [Boost-users] [proto] concise error messages

Subject: Re: [Boost-users] [proto] concise error messages
From: Joel de Guzman (joel_at_[hidden])
Date: 2010-01-23 00:35:32

On 1/23/2010 12:45 PM, Eric Niebler wrote:

> template<typename Expr>
> void check_grammar(const Expr&e)
> {
> BOOST_MPL_ASSERT_MSG((proto::matches<Expr, napl_grammar>::value),
> SYNTAX_NOT_CORRECT,
> (void));
> // Dispatch to the correct impl depending on whether we have
> // a valid expression or not.
> check_grammar_impl(e, proto::matches<Expr, napl_grammar>());
> }
>
> That should reduce the noise gcc emits when your users create invalid
> expressions.

Yep. This is essentially what Spirit does. It's not perfect, but
it works.

Regards,
-- 
Joel de Guzman
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