///////////////////////////////////////////////////////////////////////////////
/// \file regex_algorithms.hpp
/// Contains the regex_match(), regex_search() and regex_replace() algorithms.
//
//  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_ALGORITHMS_HPP_EAN_10_04_2005
#define BOOST_XPRESSIVE_ALGORITHMS_HPP_EAN_10_04_2005

// MS compatible compilers support #pragma once
#if defined(_MSC_VER) && (_MSC_VER >= 1020)
# pragma once
#endif

#include <string>
#include <iterator>
#include <boost/mpl/or.hpp>
#include <boost/range/end.hpp>
#include <boost/range/begin.hpp>
#include <boost/mpl/identity.hpp>
#include <boost/utility/enable_if.hpp>
#include <boost/type_traits/add_const.hpp>
#include <boost/type_traits/is_pointer.hpp>
#include <boost/type_traits/remove_const.hpp>
#include <boost/xpressive/match_results.hpp>
#include <boost/xpressive/detail/detail_fwd.hpp>
#include <boost/xpressive/detail/core/state.hpp>
#include <boost/xpressive/detail/utility/save_restore.hpp>

/// INTERNAL ONLY
///
#define BOOST_XPR_NONDEDUCED_TYPE_(x) typename mpl::identity<x>::type

namespace boost { namespace xpressive
{

///////////////////////////////////////////////////////////////////////////////
// regex_match
///////////////////////////////////////////////////////////////////////////////

namespace detail
{
    ///////////////////////////////////////////////////////////////////////////////
    // regex_match_impl
    template<typename BidiIter>
    inline bool regex_match_impl
    (
        BOOST_XPR_NONDEDUCED_TYPE_(BidiIter) begin
      , BOOST_XPR_NONDEDUCED_TYPE_(BidiIter) end
      , match_results<BidiIter> &what
      , basic_regex<BidiIter> const &re
      , regex_constants::match_flag_type flags = regex_constants::match_default
    )
    {
        typedef detail::core_access<BidiIter> access;
        BOOST_ASSERT(0 != re.regex_id());

        // the state object holds matching state and
        // is passed by reference to all the matchers
        detail::match_state<BidiIter> state(begin, end, what, *access::get_regex_impl(re), flags);
        state.flags_.match_all_ = true;
        state.sub_match(0).begin_ = begin;

        if(access::match(re, state))
        {
            access::set_prefix_suffix(what, begin, end);
            return true;
        }

        // handle partial matches
        else if(state.found_partial_match_ && 0 != (flags & regex_constants::match_partial))
        {
            state.set_partial_match();
            return true;
        }

        access::reset(what);
        return false;
    }
} // namespace detail

/// \brief See if a regex matches a sequence from beginning to end.
///
/// Determines whether there is an exact match between the regular expression \c re,
/// and all of the sequence <tt>[begin, end)</tt>.
///
/// \pre Type \c BidiIter meets the requirements of a Bidirectional Iterator (24.1.4).
/// \pre <tt>[begin,end)</tt> denotes a valid iterator range.
/// \param begin The beginning of the sequence.
/// \param end The end of the sequence.
/// \param what The \c match_results struct into which the sub_matches will be written
/// \param re The regular expression object to use
/// \param flags Optional match flags, used to control how the expression is matched
///        against the sequence. (See \c match_flag_type.)
/// \return \c true if a match is found, \c false otherwise
/// \throw regex_error on stack exhaustion
template<typename BidiIter>
inline bool regex_match
(
    BOOST_XPR_NONDEDUCED_TYPE_(BidiIter) begin
  , BOOST_XPR_NONDEDUCED_TYPE_(BidiIter) end
  , match_results<BidiIter> &what
  , basic_regex<BidiIter> const &re
  , regex_constants::match_flag_type flags = regex_constants::match_default
)
{
    typedef detail::core_access<BidiIter> access;

    if(0 == re.regex_id())
    {
        access::reset(what);
        return false;
    }

    return detail::regex_match_impl(begin, end, what, re, flags);
}

/// \overload
///
template<typename BidiIter>
inline bool regex_match
(
    BOOST_XPR_NONDEDUCED_TYPE_(BidiIter) begin
  , BOOST_XPR_NONDEDUCED_TYPE_(BidiIter) end
  , basic_regex<BidiIter> const &re
  , regex_constants::match_flag_type flags = regex_constants::match_default
)
{
    if(0 == re.regex_id())
    {
        return false;
    }

    // BUGBUG this is inefficient
    match_results<BidiIter> what;
    return detail::regex_match_impl(begin, end, what, re, flags);
}

/// \overload
///
template<typename Char>
inline bool regex_match
(
    BOOST_XPR_NONDEDUCED_TYPE_(Char) *begin
  , match_results<Char *> &what
  , basic_regex<Char *> const &re
  , regex_constants::match_flag_type flags = regex_constants::match_default
)
{
    typedef detail::core_access<Char *> access;

    if(0 == re.regex_id())
    {
        access::reset(what);
        return false;
    }

    // BUGBUG this is inefficient
    typedef typename remove_const<Char>::type char_type;
    Char *end = begin + std::char_traits<char_type>::length(begin);
    return detail::regex_match_impl(begin, end, what, re, flags);
}

/// \overload
///
template<typename BidiRange, typename BidiIter>
inline bool regex_match
(
    BidiRange &rng
  , match_results<BidiIter> &what
  , basic_regex<BidiIter> const &re
  , regex_constants::match_flag_type flags = regex_constants::match_default
  , typename disable_if<detail::is_char_ptr<BidiRange> >::type * = 0
)
{
    typedef detail::core_access<BidiIter> access;

    if(0 == re.regex_id())
    {
        access::reset(what);
        return false;
    }

    // Note that the result iterator of the range must be convertible
    // to BidiIter here.
    BidiIter begin = boost::begin(rng), end = boost::end(rng);
    return detail::regex_match_impl(begin, end, what, re, flags);
}

/// \overload
///
template<typename BidiRange, typename BidiIter>
inline bool regex_match
(
    BidiRange const &rng
  , match_results<BidiIter> &what
  , basic_regex<BidiIter> const &re
  , regex_constants::match_flag_type flags = regex_constants::match_default
  , typename disable_if<detail::is_char_ptr<BidiRange> >::type * = 0
)
{
    typedef detail::core_access<BidiIter> access;

    if(0 == re.regex_id())
    {
        access::reset(what);
        return false;
    }

    // Note that the result iterator of the range must be convertible
    // to BidiIter here.
    BidiIter begin = boost::begin(rng), end = boost::end(rng);
    return detail::regex_match_impl(begin, end, what, re, flags);
}

/// \overload
///
template<typename Char>
inline bool regex_match
(
    BOOST_XPR_NONDEDUCED_TYPE_(Char) *begin
  , basic_regex<Char *> const &re
  , regex_constants::match_flag_type flags = regex_constants::match_default
)
{
    if(0 == re.regex_id())
    {
        return false;
    }

    // BUGBUG this is inefficient
    match_results<Char *> what;
    typedef typename remove_const<Char>::type char_type;
    Char *end = begin + std::char_traits<char_type>::length(begin);
    return detail::regex_match_impl(begin, end, what, re, flags);
}

/// \overload
///
template<typename BidiRange, typename BidiIter>
inline bool regex_match
(
    BidiRange &rng
  , basic_regex<BidiIter> const &re
  , regex_constants::match_flag_type flags = regex_constants::match_default
  , typename disable_if<detail::is_char_ptr<BidiRange> >::type * = 0
)
{
    if(0 == re.regex_id())
    {
        return false;
    }

    // BUGBUG this is inefficient
    match_results<BidiIter> what;
    // Note that the result iterator of the range must be convertible
    // to BidiIter here.
    BidiIter begin = boost::begin(rng), end = boost::end(rng);
    return detail::regex_match_impl(begin, end, what, re, flags);
}

/// \overload
///
template<typename BidiRange, typename BidiIter>
inline bool regex_match
(
    BidiRange const &rng
  , basic_regex<BidiIter> const &re
  , regex_constants::match_flag_type flags = regex_constants::match_default
  , typename disable_if<detail::is_char_ptr<BidiRange> >::type * = 0
)
{
    if(0 == re.regex_id())
    {
        return false;
    }

    // BUGBUG this is inefficient
    match_results<BidiIter> what;
    // Note that the result iterator of the range must be convertible
    // to BidiIter here.
    BidiIter begin = boost::begin(rng), end = boost::end(rng);
    return detail::regex_match_impl(begin, end, what, re, flags);
}


///////////////////////////////////////////////////////////////////////////////
// regex_search
///////////////////////////////////////////////////////////////////////////////

namespace detail
{
    ///////////////////////////////////////////////////////////////////////////////
    // regex_search_impl
    template<typename BidiIter>
    inline bool regex_search_impl
    (
        match_state<BidiIter> &state
      , basic_regex<BidiIter> const &re
      , bool not_initial_null = false
    )
    {
        typedef core_access<BidiIter> access;
        typedef typename iterator_value<BidiIter>::type char_type;
        match_results<BidiIter> &what = *state.context_.results_ptr_;
        BOOST_ASSERT(0 != re.regex_id());

        bool const partial_ok = state.flags_.match_partial_;
        save_restore<bool> not_null(state.flags_.match_not_null_, state.flags_.match_not_null_ || not_initial_null);
        state.flags_.match_prev_avail_ = state.flags_.match_prev_avail_ || !state.bos();

        regex_impl<BidiIter> const &impl = *access::get_regex_impl(re);
        BidiIter const begin = state.cur_, end = state.end_;
        BidiIter &sub0begin = state.sub_match(0).begin_;
        sub0begin = state.cur_;

        // If match_continuous is set, we only need to check for a match at the current position
        if(state.flags_.match_continuous_)
        {
            if(access::match(re, state))
            {
                access::set_prefix_suffix(what, begin, end);
                return true;
            }

            // handle partial matches
            else if(partial_ok && state.found_partial_match_)
            {
                state.set_partial_match();
                return true;
            }
        }

        // If we have a finder, use it to find where a potential match can start
        else if(impl.finder_ && (!partial_ok || impl.finder_->ok_for_partial_matches()))
        {
            finder<BidiIter> const &find = *impl.finder_;
            if(find(state))
            {
                if(state.cur_ != begin)
                {
                    not_null.restore();
                }

                do
                {
                    sub0begin = state.cur_;
                    if(access::match(re, state))
                    {
                        access::set_prefix_suffix(what, begin, end);
                        return true;
                    }

                    // handle partial matches
                    else if(partial_ok && state.found_partial_match_)
                    {
                        state.set_partial_match();
                        return true;
                    }

                    BOOST_ASSERT(state.cur_ == sub0begin);
                    not_null.restore();
                }
                while(state.cur_ != state.end_ && (++state.cur_, find(state)));
            }
        }

        // Otherwise, use brute force search at every position.
        else
        {
            for(;;)
            {
                if(access::match(re, state))
                {
                    access::set_prefix_suffix(what, begin, end);
                    return true;
                }

                // handle partial matches
                else if(partial_ok && state.found_partial_match_)
                {
                    state.set_partial_match();
                    return true;
                }

                else if(end == sub0begin)
                {
                    break;
                }

                BOOST_ASSERT(state.cur_ == sub0begin);
                state.cur_ = ++sub0begin;
                not_null.restore();
            }
        }

        access::reset(what);
        return false;
    }
} // namespace detail


/// \brief Determines whether there is some sub-sequence within <tt>[begin,end)</tt>
/// that matches the regular expression \c re.
///
/// Determines whether there is some sub-sequence within <tt>[begin,end)</tt> that matches
/// the regular expression \c re.
///
/// \pre Type \c BidiIter meets the requirements of a Bidirectional Iterator (24.1.4).
/// \pre <tt>[begin,end)</tt> denotes a valid iterator range.
/// \param begin The beginning of the sequence
/// \param end The end of the sequence
/// \param what The \c match_results struct into which the sub_matches will be written
/// \param re The regular expression object to use
/// \param flags Optional match flags, used to control how the expression is matched against
///        the sequence. (See \c match_flag_type.)
/// \return \c true if a match is found, \c false otherwise
/// \throw regex_error on stack exhaustion
template<typename BidiIter>
inline bool regex_search
(
    BOOST_XPR_NONDEDUCED_TYPE_(BidiIter) begin
  , BOOST_XPR_NONDEDUCED_TYPE_(BidiIter) end
  , match_results<BidiIter> &what
  , basic_regex<BidiIter> const &re
  , regex_constants::match_flag_type flags = regex_constants::match_default
)
{
    typedef detail::core_access<BidiIter> access;

    // a default-constructed regex matches nothing
    if(0 == re.regex_id())
    {
        access::reset(what);
        return false;
    }

    // the state object holds matching state and
    // is passed by reference to all the matchers
    detail::match_state<BidiIter> state(begin, end, what, *access::get_regex_impl(re), flags);
    return detail::regex_search_impl(state, re);
}

/// \overload
///
template<typename BidiIter>
inline bool regex_search
(
    BOOST_XPR_NONDEDUCED_TYPE_(BidiIter) begin
  , BOOST_XPR_NONDEDUCED_TYPE_(BidiIter) end
  , basic_regex<BidiIter> const &re
  , regex_constants::match_flag_type flags = regex_constants::match_default
)
{
    typedef detail::core_access<BidiIter> access;

    // a default-constructed regex matches nothing
    if(0 == re.regex_id())
    {
        return false;
    }

    // BUGBUG this is inefficient
    match_results<BidiIter> what;
    // the state object holds matching state and
    // is passed by reference to all the matchers
    detail::match_state<BidiIter> state(begin, end, what, *access::get_regex_impl(re), flags);
    return detail::regex_search_impl(state, re);
}

/// \overload
///
template<typename Char>
inline bool regex_search
(
    BOOST_XPR_NONDEDUCED_TYPE_(Char) *begin
  , match_results<Char *> &what
  , basic_regex<Char *> const &re
  , regex_constants::match_flag_type flags = regex_constants::match_default
)
{
    typedef detail::core_access<Char *> access;

    // a default-constructed regex matches nothing
    if(0 == re.regex_id())
    {
        access::reset(what);
        return false;
    }

    // BUGBUG this is inefficient
    typedef typename remove_const<Char>::type char_type;
    Char *end = begin + std::char_traits<char_type>::length(begin);
    // the state object holds matching state and
    // is passed by reference to all the matchers
    detail::match_state<Char *> state(begin, end, what, *access::get_regex_impl(re), flags);
    return detail::regex_search_impl(state, re);
}

/// \overload
///
template<typename BidiRange, typename BidiIter>
inline bool regex_search
(
    BidiRange &rng
  , match_results<BidiIter> &what
  , basic_regex<BidiIter> const &re
  , regex_constants::match_flag_type flags = regex_constants::match_default
  , typename disable_if<detail::is_char_ptr<BidiRange> >::type * = 0
)
{
    typedef detail::core_access<BidiIter> access;

    // a default-constructed regex matches nothing
    if(0 == re.regex_id())
    {
        access::reset(what);
        return false;
    }

    // Note that the result iterator of the range must be convertible
    // to BidiIter here.
    BidiIter begin = boost::begin(rng), end = boost::end(rng);
    // the state object holds matching state and
    // is passed by reference to all the matchers
    detail::match_state<BidiIter> state(begin, end, what, *access::get_regex_impl(re), flags);
    return detail::regex_search_impl(state, re);
}

/// \overload
///
template<typename BidiRange, typename BidiIter>
inline bool regex_search
(
    BidiRange const &rng
  , match_results<BidiIter> &what
  , basic_regex<BidiIter> const &re
  , regex_constants::match_flag_type flags = regex_constants::match_default
  , typename disable_if<detail::is_char_ptr<BidiRange> >::type * = 0
)
{
    typedef detail::core_access<BidiIter> access;

    // a default-constructed regex matches nothing
    if(0 == re.regex_id())
    {
        access::reset(what);
        return false;
    }

    // Note that the result iterator of the range must be convertible
    // to BidiIter here.
    BidiIter begin = boost::begin(rng), end = boost::end(rng);
    // the state object holds matching state and
    // is passed by reference to all the matchers
    detail::match_state<BidiIter> state(begin, end, what, *access::get_regex_impl(re), flags);
    return detail::regex_search_impl(state, re);
}

/// \overload
///
template<typename Char>
inline bool regex_search
(
    BOOST_XPR_NONDEDUCED_TYPE_(Char) *begin
  , basic_regex<Char *> const &re
  , regex_constants::match_flag_type flags = regex_constants::match_default
)
{
    typedef detail::core_access<Char *> access;

    // a default-constructed regex matches nothing
    if(0 == re.regex_id())
    {
        return false;
    }

    // BUGBUG this is inefficient
    match_results<Char *> what;
    // BUGBUG this is inefficient
    typedef typename remove_const<Char>::type char_type;
    Char *end = begin + std::char_traits<char_type>::length(begin);
    // the state object holds matching state and
    // is passed by reference to all the matchers
    detail::match_state<Char *> state(begin, end, what, *access::get_regex_impl(re), flags);
    return detail::regex_search_impl(state, re);
}

/// \overload
///
template<typename BidiRange, typename BidiIter>
inline bool regex_search
(
    BidiRange &rng
  , basic_regex<BidiIter> const &re
  , regex_constants::match_flag_type flags = regex_constants::match_default
  , typename disable_if<detail::is_char_ptr<BidiRange> >::type * = 0
)
{
    typedef detail::core_access<BidiIter> access;

    // a default-constructed regex matches nothing
    if(0 == re.regex_id())
    {
        return false;
    }

    // BUGBUG this is inefficient
    match_results<BidiIter> what;
    // Note that the result iterator of the range must be convertible
    // to BidiIter here.
    BidiIter begin = boost::begin(rng), end = boost::end(rng);
    // the state object holds matching state and
    // is passed by reference to all the matchers
    detail::match_state<BidiIter> state(begin, end, what, *access::get_regex_impl(re), flags);
    return detail::regex_search_impl(state, re);
}

/// \overload
///
template<typename BidiRange, typename BidiIter>
inline bool regex_search
(
    BidiRange const &rng
  , basic_regex<BidiIter> const &re
  , regex_constants::match_flag_type flags = regex_constants::match_default
  , typename disable_if<detail::is_char_ptr<BidiRange> >::type * = 0
)
{
    typedef detail::core_access<BidiIter> access;

    // a default-constructed regex matches nothing
    if(0 == re.regex_id())
    {
        return false;
    }

    // BUGBUG this is inefficient
    match_results<BidiIter> what;
    // Note that the result iterator of the range must be convertible
    // to BidiIter here.
    BidiIter begin = boost::begin(rng), end = boost::end(rng);
    // the state object holds matching state and
    // is passed by reference to all the matchers
    detail::match_state<BidiIter> state(begin, end, what, *access::get_regex_impl(re), flags);
    return detail::regex_search_impl(state, re);
}


///////////////////////////////////////////////////////////////////////////////
// regex_replace
///////////////////////////////////////////////////////////////////////////////

namespace detail
{
    ///////////////////////////////////////////////////////////////////////////////
    // regex_replace_impl
    template<typename OutIter, typename BidiIter, typename Formatter>
    inline OutIter regex_replace_impl
    (
        OutIter out
      , BidiIter begin
      , BidiIter end
      , basic_regex<BidiIter> const &re
      , Formatter const &format
      , regex_constants::match_flag_type flags = regex_constants::match_default
    )
    {
        using namespace regex_constants;
        typedef detail::core_access<BidiIter> access;
        BOOST_ASSERT(0 != re.regex_id());

        BidiIter cur = begin;
        match_results<BidiIter> what;
        detail::match_state<BidiIter> state(begin, end, what, *access::get_regex_impl(re), flags);
        bool const yes_copy = (0 == (flags & format_no_copy));

        if(detail::regex_search_impl(state, re))
        {
            if(yes_copy)
            {
                out = std::copy(cur, what[0].first, out);
            }

            out = what.format(out, format, flags);
            cur = state.cur_ = state.next_search_ = what[0].second;

            if(0 == (flags & format_first_only))
            {
                bool not_null = (0 == what.length());
                state.reset(what, *access::get_regex_impl(re));
                while(detail::regex_search_impl(state, re, not_null))
                {
                    if(yes_copy)
                    {
                        out = std::copy(cur, what[0].first, out);
                    }

                    access::set_prefix_suffix(what, begin, end);
                    out = what.format(out, format, flags);
                    cur = state.cur_ = state.next_search_ = what[0].second;
                    not_null = (0 == what.length());
                    state.reset(what, *access::get_regex_impl(re));
                }
            }
        }

        if(yes_copy)
        {
            out = std::copy(cur, end, out);
        }

        return out;
    }
} // namespace detail

/// \brief Build an output sequence given an input sequence, a regex, and a format string or
/// a formatter object, function, or expression.
///
/// Constructs a \c regex_iterator object: <tt>regex_iterator\< BidiIter \> i(begin, end, re, flags)</tt>,
/// and uses \c i to enumerate through all of the matches m of type <tt>match_results\< BidiIter \></tt> that
/// occur within the sequence <tt>[begin, end)</tt>. If no such matches are found and <tt>!(flags \& format_no_copy)</tt>
/// then calls <tt>std::copy(begin, end, out)</tt>. Otherwise, for each match found, if <tt>!(flags \& format_no_copy)</tt>
/// calls <tt>std::copy(m.prefix().first, m.prefix().second, out)</tt>, and then calls <tt>m.format(out, format, flags)</tt>.
/// Finally if <tt>!(flags \& format_no_copy)</tt> calls <tt>std::copy(last_m.suffix().first, last_m.suffix().second, out)</tt>
/// where \c last_m is a copy of the last match found.
///
/// If <tt>flags \& format_first_only</tt> is non-zero then only the first match found is replaced.
///
/// \pre Type \c BidiIter meets the requirements of a Bidirectional Iterator (24.1.4).
/// \pre Type \c OutIter meets the requirements of an Output Iterator (24.1.2).
/// \pre Type \c Formatter models \c ForwardRange, <tt>Callable\<match_results\<BidiIter\> \></tt>,
///      <tt>Callable\<match_results\<BidiIter\>, OutIter\></tt>, or
///      <tt>Callable\<match_results\<BidiIter\>, OutIter, regex_constants::match_flag_type\></tt>;
///      or else it is a null-terminated format string, or an expression template
///      representing a formatter lambda expression.
/// \pre <tt>[begin,end)</tt> denotes a valid iterator range.
/// \param out An output iterator into which the output sequence is written.
/// \param begin The beginning of the input sequence.
/// \param end The end of the input sequence.
/// \param re The regular expression object to use.
/// \param format The format string used to format the replacement sequence,
///        or a formatter function, function object, or expression.
/// \param flags Optional match flags, used to control how the expression is matched against
///        the sequence. (See \c match_flag_type.)
/// \return The value of the output iterator after the output sequence has been written to it.
/// \throw regex_error on stack exhaustion or invalid format string.
template<typename OutIter, typename BidiIter, typename Formatter>
inline OutIter regex_replace
(
    OutIter out
  , BOOST_XPR_NONDEDUCED_TYPE_(BidiIter) begin
  , BOOST_XPR_NONDEDUCED_TYPE_(BidiIter) end
  , basic_regex<BidiIter> const &re
  , Formatter const &format
  , regex_constants::match_flag_type flags = regex_constants::match_default
  , typename disable_if<detail::is_char_ptr<Formatter> >::type * = 0
)
{
    // Default-constructed regexes match nothing
    if(0 == re.regex_id())
    {
        if((0 == (flags & regex_constants::format_no_copy)))
        {
            out = std::copy(begin, end, out);
        }

        return out;
    }

    return detail::regex_replace_impl(out, begin, end, re, format, flags);
}

/// \overload
///
template<typename OutIter, typename BidiIter>
inline OutIter regex_replace
(
    OutIter out
  , BOOST_XPR_NONDEDUCED_TYPE_(BidiIter) begin
  , BOOST_XPR_NONDEDUCED_TYPE_(BidiIter) end
  , basic_regex<BidiIter> const &re
  , typename iterator_value<BidiIter>::type const *format
  , regex_constants::match_flag_type flags = regex_constants::match_default
)
{
    // Default-constructed regexes match nothing
    if(0 == re.regex_id())
    {
        if((0 == (flags & regex_constants::format_no_copy)))
        {
            out = std::copy(begin, end, out);
        }

        return out;
    }

    return detail::regex_replace_impl(out, begin, end, re, format, flags);
}

/// \overload
///
template<typename BidiContainer, typename BidiIter, typename Formatter>
inline BidiContainer regex_replace
(
    BidiContainer &str
  , basic_regex<BidiIter> const &re
  , Formatter const &format
  , regex_constants::match_flag_type flags = regex_constants::match_default
  , typename disable_if<mpl::or_<detail::is_char_ptr<BidiContainer>, detail::is_char_ptr<Formatter> > >::type * = 0
)
{
    BidiContainer result;
    // Note that the result iterator of the range must be convertible
    // to BidiIter here.
    BidiIter begin = boost::begin(str), end = boost::end(str);

    // Default-constructed regexes match nothing
    if(0 == re.regex_id())
    {
        if((0 == (flags & regex_constants::format_no_copy)))
        {
            std::copy(begin, end, std::back_inserter(result));
        }

        return result;
    }

    detail::regex_replace_impl(std::back_inserter(result), begin, end, re, format, flags);
    return result;
}

/// \overload
///
template<typename BidiContainer, typename BidiIter, typename Formatter>
inline BidiContainer regex_replace
(
    BidiContainer const &str
  , basic_regex<BidiIter> const &re
  , Formatter const &format
  , regex_constants::match_flag_type flags = regex_constants::match_default
  , typename disable_if<mpl::or_<detail::is_char_ptr<BidiContainer>, detail::is_char_ptr<Formatter> > >::type * = 0
)
{
    BidiContainer result;
    // Note that the result iterator of the range must be convertible
    // to BidiIter here.
    BidiIter begin = boost::begin(str), end = boost::end(str);

    // Default-constructed regexes match nothing
    if(0 == re.regex_id())
    {
        if((0 == (flags & regex_constants::format_no_copy)))
        {
            std::copy(begin, end, std::back_inserter(result));
        }

        return result;
    }

    detail::regex_replace_impl(std::back_inserter(result), begin, end, re, format, flags);
    return result;
}

/// \overload
///
template<typename Char, typename Formatter>
inline std::basic_string<typename remove_const<Char>::type> regex_replace
(
    BOOST_XPR_NONDEDUCED_TYPE_(Char) *str
  , basic_regex<Char *> const &re
  , Formatter const &format
  , regex_constants::match_flag_type flags = regex_constants::match_default
  , typename disable_if<detail::is_char_ptr<Formatter> >::type * = 0
)
{
    typedef typename remove_const<Char>::type char_type;
    std::basic_string<char_type> result;

    // Default-constructed regexes match nothing
    if(0 == re.regex_id())
    {
        if((0 == (flags & regex_constants::format_no_copy)))
        {
            result = str;
        }

        return result;
    }

    Char *end = str + std::char_traits<char_type>::length(str);
    detail::regex_replace_impl(std::back_inserter(result), str, end, re, format, flags);
    return result;
}

/// \overload
///
template<typename BidiContainer, typename BidiIter>
inline BidiContainer regex_replace
(
    BidiContainer &str
  , basic_regex<BidiIter> const &re
  , typename iterator_value<BidiIter>::type const *format
  , regex_constants::match_flag_type flags = regex_constants::match_default
  , typename disable_if<detail::is_char_ptr<BidiContainer> >::type * = 0
)
{
    BidiContainer result;
    // Note that the result iterator of the range must be convertible
    // to BidiIter here.
    BidiIter begin = boost::begin(str), end = boost::end(str);

    // Default-constructed regexes match nothing
    if(0 == re.regex_id())
    {
        if((0 == (flags & regex_constants::format_no_copy)))
        {
            std::copy(begin, end, std::back_inserter(result));
        }

        return result;
    }

    detail::regex_replace_impl(std::back_inserter(result), begin, end, re, format, flags);
    return result;
}

/// \overload
///
template<typename BidiContainer, typename BidiIter>
inline BidiContainer regex_replace
(
    BidiContainer const &str
  , basic_regex<BidiIter> const &re
  , typename iterator_value<BidiIter>::type const *format
  , regex_constants::match_flag_type flags = regex_constants::match_default
  , typename disable_if<detail::is_char_ptr<BidiContainer> >::type * = 0
)
{
    BidiContainer result;
    // Note that the result iterator of the range must be convertible
    // to BidiIter here.
    BidiIter begin = boost::begin(str), end = boost::end(str);

    // Default-constructed regexes match nothing
    if(0 == re.regex_id())
    {
        if((0 == (flags & regex_constants::format_no_copy)))
        {
            std::copy(begin, end, std::back_inserter(result));
        }

        return result;
    }

    detail::regex_replace_impl(std::back_inserter(result), begin, end, re, format, flags);
    return result;
}

/// \overload
///
template<typename Char>
inline std::basic_string<typename remove_const<Char>::type> regex_replace
(
    BOOST_XPR_NONDEDUCED_TYPE_(Char) *str
  , basic_regex<Char *> const &re
  , typename add_const<Char>::type *format
  , regex_constants::match_flag_type flags = regex_constants::match_default
)
{
    typedef typename remove_const<Char>::type char_type;
    std::basic_string<char_type> result;

    // Default-constructed regexes match nothing
    if(0 == re.regex_id())
    {
        if((0 == (flags & regex_constants::format_no_copy)))
        {
            result = str;
        }

        return result;
    }

    Char *end = str + std::char_traits<char_type>::length(str);
    detail::regex_replace_impl(std::back_inserter(result), str, end, re, format, flags);
    return result;
}

}} // namespace boost::xpressive

#endif