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//  Copyright (c) 2001-2011 Hartmut Kaiser
//  Distributed under the Boost Software License, Version 1.0. (See accompanying 
//  file LICENSE_1_0.txt or copy at

#if !defined(BOOST_SPIRIT_WHAT_MAY_04_2007_0116PM)
#define BOOST_SPIRIT_WHAT_MAY_04_2007_0116PM

#if defined(_MSC_VER)
#pragma once

#include <boost/mpl/assert.hpp>
#include <boost/spirit/home/support/info.hpp>
#include <boost/spirit/home/karma/meta_compiler.hpp>

namespace boost { namespace spirit { namespace karma
    template <typename Expr>
    inline info what(Expr const& xpr)
        // Report invalid expression error as early as possible.
        // If you got an error_invalid_expression
        // error message here, then the expression (expr) is not a
        // valid spirit karma expression.
        BOOST_SPIRIT_ASSERT_MATCH(karma::domain, Expr);
        return compile<karma::domain>(xpr).what(unused);