text: // ----------------------------------------------------------------------------
  // format_implementation.hpp  Implementation of the basic_format class
  // ----------------------------------------------------------------------------
  
  //  Copyright Samuel Krempp 2003. Use, modification, and distribution are
  //  subject to 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)
  
  //  See http://www.boost.org/libs/format for library home page
  
  
  // ----------------------------------------------------------------------------
  
  #ifndef BOOST_FORMAT_IMPLEMENTATION_HPP
  #define BOOST_FORMAT_IMPLEMENTATION_HPP
  
  #include <boost/config.hpp>
  #include <boost/throw_exception.hpp>
  #include <boost/assert.hpp>
  #include <boost/format/format_class.hpp>
  #include <algorithm> // std::swap
  
  namespace boost {
  
  // ---  basic_format implementation -----------------------------------------//
  
      template< class Ch, class Tr, class Alloc>
      basic_format<Ch, Tr, Alloc>:: basic_format(const Ch* s)
          : style_(0), cur_arg_(0), num_args_(0), dumped_(false),
            exceptions_(io::all_error_bits)
      {
          if( s)
              parse( s );
      }
  
  #if !defined(BOOST_NO_STD_LOCALE)
      template< class Ch, class Tr, class Alloc>
      basic_format<Ch, Tr, Alloc>:: basic_format(const Ch* s, const std::locale & loc)
          : style_(0), cur_arg_(0), num_args_(0), dumped_(false),
            exceptions_(io::all_error_bits), loc_(loc)
      {
          if(s) parse( s );
      }
  
      template< class Ch, class Tr, class Alloc>
      basic_format<Ch, Tr, Alloc>:: basic_format(const string_type& s, const std::locale & loc)
          : style_(0), cur_arg_(0), num_args_(0), dumped_(false),
            exceptions_(io::all_error_bits), loc_(loc)
      {
          parse(s);  
      }
  #endif // ! BOOST_NO_STD_LOCALE
      template< class Ch, class Tr, class Alloc>
      io::detail::locale_t basic_format<Ch, Tr, Alloc>:: 
      getloc() const {
          return loc_ ? loc_.get() : io::detail::locale_t(); 
      }
  
      template< class Ch, class Tr, class Alloc>
      basic_format<Ch, Tr, Alloc>:: basic_format(const string_type& s)
          : style_(0), cur_arg_(0), num_args_(0), dumped_(false),
            exceptions_(io::all_error_bits)
      {
          parse(s);  
      }
  
      template< class Ch, class Tr, class Alloc> // just don't copy the buf_ member
      basic_format<Ch, Tr, Alloc>:: basic_format(const basic_format& x)
          : items_(x.items_), bound_(x.bound_), style_(x.style_),
            cur_arg_(x.cur_arg_), num_args_(x.num_args_), dumped_(x.dumped_),
            prefix_(x.prefix_), exceptions_(x.exceptions_), loc_(x.loc_)
      {
      }
  
      template< class Ch, class Tr, class Alloc>  // just don't copy the buf_ member
      basic_format<Ch, Tr, Alloc>& basic_format<Ch, Tr, Alloc>:: 
      operator= (const basic_format& x) {
          if(this == &x)
              return *this;
          (basic_format<Ch, Tr, Alloc>(x)).swap(*this);
          return *this;
      }
      template< class Ch, class Tr, class Alloc>
      void  basic_format<Ch, Tr, Alloc>:: 
      swap (basic_format & x) {
          std::swap(exceptions_, x.exceptions_);
          std::swap(style_, x.style_); 
          std::swap(cur_arg_, x.cur_arg_); 
          std::swap(num_args_, x.num_args_);
          std::swap(dumped_, x.dumped_);
  
          items_.swap(x.items_);
          prefix_.swap(x.prefix_);
          bound_.swap(x.bound_);
      }
  
      template< class Ch, class Tr, class Alloc>
      unsigned char basic_format<Ch,Tr, Alloc>:: exceptions() const {
          return exceptions_; 
      }
  
      template< class Ch, class Tr, class Alloc>
      unsigned char basic_format<Ch,Tr, Alloc>:: exceptions(unsigned char newexcept) { 
          unsigned char swp = exceptions_; 
          exceptions_ = newexcept; 
          return swp; 
      }
  
      template<class Ch, class Tr, class Alloc>
      void basic_format<Ch, Tr, Alloc>:: 
      make_or_reuse_data (std::size_t nbitems) {
  #if !defined(BOOST_NO_STD_LOCALE)
          Ch fill = ( BOOST_USE_FACET(std::ctype<Ch>, getloc()) ). widen(' ');
  #else
          Ch fill = ' ';
  #endif
          if(items_.size() == 0)
              items_.assign( nbitems, format_item_t(fill) );
          else {
              if(nbitems>items_.size())
                  items_.resize(nbitems, format_item_t(fill));
              bound_.resize(0);
              for(std::size_t i=0; i < nbitems; ++i)
                  items_[i].reset(fill); //  strings are resized, instead of reallocated
          }
          prefix_.resize(0);
      }
  
      template< class Ch, class Tr, class Alloc>
      basic_format<Ch,Tr, Alloc>& basic_format<Ch,Tr, Alloc>:: 
      clear () {
          // empty the string buffers (except bound arguments)
          // and make the format object ready for formatting a new set of arguments
  
          BOOST_ASSERT( bound_.size()==0 || num_args_ == static_cast<int>(bound_.size()) );
  
          for(unsigned long i=0; i<items_.size(); ++i) {
              // clear converted strings only if the corresponding argument is not  bound :
              if( bound_.size()==0 || items_[i].argN_<0 || !bound_[ items_[i].argN_ ] )
                  items_[i].res_.resize(0);
          }
          cur_arg_=0; dumped_=false;
          // maybe first arg is bound:
          if(bound_.size() != 0) {
              for(; cur_arg_ < num_args_ && bound_[cur_arg_]; ++cur_arg_)
                  {}
          }
          return *this;
      }
  
      template< class Ch, class Tr, class Alloc>
      basic_format<Ch,Tr, Alloc>& basic_format<Ch,Tr, Alloc>:: 
      clear_binds () {
          // remove all binds, then clear()
          bound_.resize(0);
          clear();
          return *this;
      }
  
      template< class Ch, class Tr, class Alloc>
      basic_format<Ch,Tr, Alloc>& basic_format<Ch,Tr, Alloc>:: 
      clear_bind (int argN) {
          // remove the bind of ONE argument then clear()
          if(argN<1 || argN > num_args_ || bound_.size()==0 || !bound_[argN-1] ) {
              if( exceptions() & io::out_of_range_bit)
                  boost::throw_exception(io::out_of_range(argN, 1, num_args_+1 ) ); 
              else return *this;
          }
          bound_[argN-1]=false;
          clear();
          return *this;
      }
  
      template< class Ch, class Tr, class Alloc>
      int basic_format<Ch,Tr, Alloc>::
      bound_args() const {
          if(bound_.size()==0)
              return 0;
          int n=0;
          for(int i=0; i<num_args_ ; ++i)
              if(bound_[i])
                  ++n;
          return n;
      }
  
      template< class Ch, class Tr, class Alloc>
      int basic_format<Ch,Tr, Alloc>::
      fed_args() const {
          if(bound_.size()==0)
              return cur_arg_;
          int n=0;
          for(int i=0; i<cur_arg_ ; ++i)
              if(!bound_[i])
                  ++n;
          return n;
      }
  
      template< class Ch, class Tr, class Alloc>
      int basic_format<Ch,Tr, Alloc>::
      cur_arg() const {
        return cur_arg_+1; }
  
      template< class Ch, class Tr, class Alloc>
      int basic_format<Ch,Tr, Alloc>::
      remaining_args() const {
          if(bound_.size()==0)
              return num_args_-cur_arg_;
          int n=0;
          for(int i=cur_arg_; i<num_args_ ; ++i)
              if(!bound_[i])
                  ++n;
          return n;
      }
  
      template< class Ch, class Tr, class Alloc>
      typename basic_format<Ch, Tr, Alloc>::string_type 
      basic_format<Ch,Tr, Alloc>:: 
      str () const {
          if(items_.size()==0)
              return prefix_;
          if( cur_arg_ < num_args_)
              if( exceptions() & io::too_few_args_bit )
                  // not enough variables supplied
                  boost::throw_exception(io::too_few_args(cur_arg_, num_args_)); 
  
          unsigned long i;
          string_type res;
          res.reserve(size());
          res += prefix_;
          for(i=0; i < items_.size(); ++i) {
              const format_item_t& item = items_[i];
              res += item.res_;
              if( item.argN_ == format_item_t::argN_tabulation) { 
                  BOOST_ASSERT( item.pad_scheme_ & format_item_t::tabulation);
                  if( static_cast<size_type>(item.fmtstate_.width_) > res.size() )
                      res.append( static_cast<size_type>(item.fmtstate_.width_) - res.size(),
                                          item.fmtstate_.fill_ );
              }
              res += item.appendix_;
          }
          dumped_=true;
          return res;
      }
      template< class Ch, class Tr, class Alloc>
      typename std::basic_string<Ch, Tr, Alloc>::size_type  basic_format<Ch,Tr, Alloc>:: 
      size () const {
  #ifdef BOOST_MSVC
         // If std::min<unsigned> or std::max<unsigned> are already instantiated
         // at this point then we get a blizzard of warning messages when we call
         // those templates with std::size_t as arguments.  Weird and very annoyning...
  #pragma warning(push)
  #pragma warning(disable:4267)
  #endif
          BOOST_USING_STD_MAX();
          size_type sz = prefix_.size();
          unsigned long i;
          for(i=0; i < items_.size(); ++i) {
              const format_item_t& item = items_[i];
              sz += item.res_.size();
              if( item.argN_ == format_item_t::argN_tabulation)
                  sz = max BOOST_PREVENT_MACRO_SUBSTITUTION (sz,
                                          static_cast<size_type>(item.fmtstate_.width_) );
              sz += item.appendix_.size();
          }
          return sz;
  #ifdef BOOST_MSVC
  #pragma warning(pop)
  #endif
      }
  
  namespace io {
  namespace detail {
  
      template<class Ch, class Tr, class Alloc, class T> 
      basic_format<Ch, Tr, Alloc>&  
      bind_arg_body (basic_format<Ch, Tr, Alloc>& self, int argN, const T& val) {
          // bind one argument to a fixed value
          // this is persistent over clear() calls, thus also over str() and <<
          if(self.dumped_) 
              self.clear(); // needed because we will modify cur_arg_
          if(argN<1 || argN > self.num_args_) {
              if( self.exceptions() & io::out_of_range_bit )
                  boost::throw_exception(io::out_of_range(argN, 1, self.num_args_+1 ) );
              else return self;
          }
          if(self.bound_.size()==0) 
              self.bound_.assign(self.num_args_,false);
          else 
              BOOST_ASSERT( self.num_args_ == static_cast<signed int>(self.bound_.size()) );
          int o_cur_arg = self.cur_arg_;
          self.cur_arg_ = argN-1; // arrays begin at 0
  
          self.bound_[self.cur_arg_]=false; // if already set, we unset and re-sets..
          self.operator%(val); // put val at the right place, because cur_arg is set
      
  
          // Now re-position cur_arg before leaving :
          self.cur_arg_ = o_cur_arg; 
          self.bound_[argN-1]=true;
          if(self.cur_arg_ == argN-1 ) {
              // hum, now this arg is bound, so move to next free arg
              while(self.cur_arg_ < self.num_args_ && self.bound_[self.cur_arg_])   
                  ++self.cur_arg_;
          }
          // In any case, we either have all args, or are on an unbound arg :
          BOOST_ASSERT( self.cur_arg_ >= self.num_args_ || ! self.bound_[self.cur_arg_]);
          return self;
      }
  
      template<class Ch, class Tr, class Alloc, class T> basic_format<Ch, Tr, Alloc>&
      modify_item_body (basic_format<Ch, Tr, Alloc>& self, int itemN, T manipulator) {
          // applies a manipulator to the format_item describing a given directive.
          // this is a permanent change, clear or reset won't cancel that.
          if(itemN<1 || itemN > static_cast<signed int>(self.items_.size() )) {
              if( self.exceptions() & io::out_of_range_bit ) 
                  boost::throw_exception(io::out_of_range(itemN, 1, static_cast<int>(self.items_.size()) ));
              else return self;
          }
          self.items_[itemN-1].fmtstate_. template apply_manip<T> ( manipulator );
          return self;
      }
  
  } // namespace detail
  } // namespace io
  } // namespace boost
  
  
  
  #endif  // BOOST_FORMAT_IMPLEMENTATION_HPP
  