You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

84 lines
2.3 KiB

///////////////////////////////////////////////////////////////////////////////
// logical_newline_matcher.hpp
//
// Copyright 2008 Eric Niebler. 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 BOOST_XPRESSIVE_DETAIL_CORE_MATCHER_LOGICAL_NEWLINE_MATCHER_HPP_EAN_10_04_2005
#define BOOST_XPRESSIVE_DETAIL_CORE_MATCHER_LOGICAL_NEWLINE_MATCHER_HPP_EAN_10_04_2005
// MS compatible compilers support #pragma once
#if defined(_MSC_VER)
# pragma once
#endif
#include <boost/xpressive/detail/detail_fwd.hpp>
#include <boost/xpressive/detail/core/quant_style.hpp>
#include <boost/xpressive/detail/core/state.hpp>
namespace boost { namespace xpressive { namespace detail
{
//////////////////////////////////////////////////////////////////////////
// logical_newline_matcher
//
template<typename Traits>
struct logical_newline_matcher
: quant_style_variable_width
{
typedef typename Traits::char_type char_type;
typedef typename Traits::char_class_type char_class_type;
logical_newline_matcher(Traits const &tr)
: newline_(lookup_classname(tr, "newline"))
, nl_(tr.widen('\n'))
, cr_(tr.widen('\r'))
{
}
template<typename BidiIter, typename Next>
bool match(match_state<BidiIter> &state, Next const &next) const
{
if(state.eos())
{
return false;
}
char_type ch = *state.cur_;
if(traits_cast<Traits>(state).isctype(ch, this->newline_))
{
++state.cur_;
if(this->cr_ == ch && !state.eos() && this->nl_ == *state.cur_)
{
++state.cur_;
if(next.match(state))
{
return true;
}
--state.cur_;
}
else if(next.match(state))
{
return true;
}
--state.cur_;
}
return false;
}
char_class_type newline() const
{
return this->newline_;
}
private:
char_class_type newline_;
char_type nl_, cr_;
};
}}}
#endif