Sprout/sprout/weed/parser/directive/replace.hpp
2014-01-08 16:48:12 +09:00

112 lines
3.3 KiB
C++

/*=============================================================================
Copyright (c) 2011-2014 Bolero MURAKAMI
https://github.com/bolero-MURAKAMI/Sprout
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)
=============================================================================*/
#ifndef SPROUT_WEED_PARSER_DIRECTIVE_REPLACE_HPP
#define SPROUT_WEED_PARSER_DIRECTIVE_REPLACE_HPP
#include <cstddef>
#include <sprout/config.hpp>
#include <sprout/type_traits/identity.hpp>
#include <sprout/weed/unused.hpp>
#include <sprout/weed/parser_result.hpp>
#include <sprout/weed/expr/make_terminal_or_expr.hpp>
#include <sprout/weed/expr/eval.hpp>
#include <sprout/weed/parser/parser_base.hpp>
#include <sprout/weed/traits/expr/terminal_or_expr_of.hpp>
#include <sprout/weed/traits/parser/attribute_of.hpp>
namespace sprout {
namespace weed {
//
// replace_p
//
template<typename Parser, typename T>
struct replace_p
: public sprout::weed::parser_base
{
public:
typedef T value_type;
template<typename Context, typename Iterator>
struct attribute
: public sprout::identity<value_type>
{};
template<typename Context, typename Iterator>
struct result
: public sprout::identity<sprout::weed::parser_result<Iterator, typename attribute<Context, Iterator>::type> >
{};
private:
typedef typename sprout::weed::traits::terminal_or_expr_of<Parser>::type expr_type;
private:
expr_type expr_;
value_type value_;
private:
template<typename Context, typename Iterator, typename Result>
SPROUT_CONSTEXPR typename result<Context, Iterator>::type call(
Iterator first,
Result const& res
) const
{
typedef typename result<Context, Iterator>::type result_type;
return res.success()
? result_type(true, res.current(), value_)
: result_type(false, first, value_)
;
}
public:
replace_p() = default;
SPROUT_CONSTEXPR replace_p(
Parser const& p,
value_type const& value
)
: expr_(sprout::weed::make_terminal_or_expr(p))
, value_(value)
{}
template<typename Context, typename Iterator>
SPROUT_CONSTEXPR typename result<Context, Iterator>::type operator()(
Iterator first, Iterator,
Context const& ctx
) const
{
return call<Context>(first, sprout::weed::eval(expr_, ctx));
}
};
//
// replace_d
//
template<typename T>
struct replace_d {
public:
typedef T value_type;
private:
value_type value_;
public:
explicit SPROUT_CONSTEXPR replace_d(value_type const& value)
: value_(value)
{}
template<typename Parser>
SPROUT_CONSTEXPR sprout::weed::replace_p<Parser, value_type> operator[](Parser const& p) const {
return sprout::weed::replace_p<Parser, value_type>(p, value_);
}
};
//
// replace_g
//
struct replace_g {
public:
template<typename T>
SPROUT_CONSTEXPR sprout::weed::replace_d<T> operator()(T const& value) const {
return sprout::weed::replace_d<T>(value);
}
};
//
// replace
//
SPROUT_CONSTEXPR sprout::weed::replace_g replace = sprout::weed::replace_g();
} // namespace weed
} // namespace sprout
#endif // #ifndef SPROUT_WEED_PARSER_DIRECTIVE_REPLACE_HPP