boost/spirit/home/qi/directive/expect.hpp
/*=============================================================================
Copyright (c) 2016 Frank Hein, maxence business consulting gmbh
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
==============================================================================*/
#if !defined (SPIRIT_EXPECT_JULY_13_2016)
#define SPIRIT_EXPECT_JULY_13_2016
#if defined(_MSC_VER)
#pragma once
#endif
#include <boost/spirit/home/qi/meta_compiler.hpp>
#include <boost/spirit/home/support/has_semantic_action.hpp>
#include <boost/spirit/home/qi/detail/attributes.hpp>
#include <boost/spirit/home/qi/detail/expectation_failure.hpp>
#include <boost/spirit/home/support/common_terminals.hpp>
#include <boost/spirit/home/support/handles_container.hpp>
#include <boost/spirit/home/support/unused.hpp>
#include <boost/spirit/home/support/info.hpp>
namespace boost { namespace spirit {
///////////////////////////////////////////////////////////////////////////
// Enablers
///////////////////////////////////////////////////////////////////////////
template <>
struct use_directive<qi::domain, tag::expect> // enables expect[p]
: mpl::true_ {};
}}
namespace boost { namespace spirit { namespace qi {
#ifndef BOOST_SPIRIT_NO_PREDEFINED_TERMINALS
using spirit::expect;
#endif
using spirit::expect_type;
template <typename Subject>
struct expect_directive : unary_parser<expect_directive<Subject> >
{
typedef result_of::compile<domain, Subject> subject_type;
template <typename Context, typename Iterator>
struct attribute
{
typedef traits::attribute_of<subject_type, Context, Iterator>
type;
};
expect_directive(Subject const& subject_) : subject(subject_) {}
template <typename Iterator, typename Context
, typename Skipper, typename Attribute>
bool parse(Iterator& first, Iterator const& last
, Context& context, Skipper const& skipper
, Attribute& attr_) const
{
typedef expectation_failure<Iterator> exception;
if (!subject.parse(first, last, context, skipper, attr_))
{
boost::throw_exception(
exception(first, last, subject.what(context)));
#if defined(BOOST_NO_EXCEPTIONS)
return false; // for systems not supporting exceptions
#endif
}
return true;
}
template <typename Context>
info what(Context& context) const
{
return info("expect", subject.what(context));
}
Subject subject;
};
///////////////////////////////////////////////////////////////////////////
// Parser generators: make_xxx function (objects)
///////////////////////////////////////////////////////////////////////////
template <typename Subject, typename Modifiers>
struct make_directive<tag::expect, Subject, Modifiers>
{
typedef expect_directive<Subject> result_type;
result_type operator()
(unused_type, Subject const& subject, unused_type) const
{
return result_type(subject);
}
};
}}}
namespace boost { namespace spirit { namespace traits {
///////////////////////////////////////////////////////////////////////////
template <typename Subject>
struct has_semantic_action<qi::expect_directive<Subject> >
: unary_has_semantic_action<Subject> {};
///////////////////////////////////////////////////////////////////////////
template <typename Subject, typename Attribute
, typename Context, typename Iterator>
struct handles_container<
qi::expect_directive<Subject>, Attribute, Context, Iterator
>
: unary_handles_container<Subject, Attribute, Context, Iterator> {};
}}}
#endif