/////////////////////////////////////////////////////////////////////////////// | |
// assert_bol_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_ASSERT_BOL_MATCHER_HPP_EAN_10_04_2005 | |
#define BOOST_XPRESSIVE_DETAIL_CORE_MATCHER_ASSERT_BOL_MATCHER_HPP_EAN_10_04_2005 | |
// MS compatible compilers support #pragma once | |
#if defined(_MSC_VER) && (_MSC_VER >= 1020) | |
# pragma once | |
#endif | |
#include <boost/next_prior.hpp> | |
#include <boost/xpressive/detail/detail_fwd.hpp> | |
#include <boost/xpressive/detail/core/quant_style.hpp> | |
#include <boost/xpressive/detail/core/state.hpp> | |
#include <boost/xpressive/detail/core/matcher/assert_line_base.hpp> | |
namespace boost { namespace xpressive { namespace detail | |
{ | |
/////////////////////////////////////////////////////////////////////////////// | |
// assert_bol_matcher | |
// | |
template<typename Traits> | |
struct assert_bol_matcher | |
: assert_line_base<Traits> | |
{ | |
typedef typename Traits::char_type char_type; | |
assert_bol_matcher(Traits const &tr) | |
: assert_line_base<Traits>(tr) | |
{ | |
} | |
template<typename BidiIter, typename Next> | |
bool match(match_state<BidiIter> &state, Next const &next) const | |
{ | |
if(state.bos()) | |
{ | |
if(!state.flags_.match_bol_) | |
{ | |
return false; | |
} | |
} | |
else | |
{ | |
char_type ch = *boost::prior(state.cur_); | |
// If the previous character is not a newline, we're not at the start of a line | |
if(!traits_cast<Traits>(state).isctype(ch, this->newline_)) | |
{ | |
return false; | |
} | |
// There is no line-break between \r and \n | |
else if(ch == this->cr_ && !state.eos() && *state.cur_ == this->nl_) | |
{ | |
return false; | |
} | |
} | |
return next.match(state); | |
} | |
}; | |
}}} | |
#endif |