C++ ios_base::width方法代码示例

num_put<Pt::Char, ostreambuf_iterator<Pt::Char> >::iter_type
num_put<Pt::Char, ostreambuf_iterator<Pt::Char> >::do_put(iter_type s, ios_base& f, char_type fill, bool val) const
{
    if( 0 == (f.flags() & ios_base::boolalpha) )
        return do_put(s, f, fill, static_cast<long>(val));
    
    typedef Pt::Char char_type;
    const numpunct<char_type>& np = use_facet< numpunct<char_type> >( f.getloc() );
 
    Pt::String str = val ? np.truename() : np.falsename();
 
    streamsize width = f.width(0);
   
    if( str.size() >= static_cast<std::size_t>(width) )
    {
        return std::copy(str.begin(), str.end(), s);
    }

    streamsize pad = width - str.size();
    ios_base::fmtflags dir = f.flags() & ios_base::adjustfield;

    if (dir == ios_base::left) 
    {
       std::copy(str.begin(), str.end(), s);
       std::fill_n(s, pad, fill);
       return s;
    }

    // right/internal padding 
    std::fill_n(s, pad, fill);
    return std::copy(str.begin(), str.end(), s);
}

num_put<Pt::Char, ostreambuf_iterator<Pt::Char> >::iter_type
num_put<Pt::Char, ostreambuf_iterator<Pt::Char> >::do_put(iter_type s, ios_base& f, char_type fill, const void* ptr) const
{
    std::size_t val = reinterpret_cast<std::size_t>(ptr);
    putHex(s, val, f.flags(), f.width(0), fill);
    return s;
}

num_put<Pt::Char, ostreambuf_iterator<Pt::Char> >::iter_type
num_put<Pt::Char, ostreambuf_iterator<Pt::Char> >::do_put(iter_type s, ios_base& f, char_type fill, unsigned long long val) const
{
	// TODO: grouping
    //const numpunct<char>& np = use_facet<numpunct<char> >(f.getloc());
    //const string& grouping = np.grouping();
    
    switch (f.flags() & ios_base::basefield) 
    {
        case ios_base::oct:
            putOctal(s, val, f.flags(), f.width(0), fill);
            break;
        case ios_base::hex:
            putHex(s, val, f.flags(), f.width(0), fill);
            break;
        default:
            putDecimal(s, val, f.flags(), f.width(0), fill);
            break;
    }

    return s;
}

_OutputIter  _STLP_CALL
__put_float(__iostring &__str, _OutputIter __oi,
            ios_base& __f, char __fill,
            char __decimal_point, char __sep, 
            size_t __group_pos, const string& __grouping) {
  if ((__group_pos < __str.size()) && (__str[__group_pos] == '.')) {
    __str[__group_pos] = __decimal_point;
  }

  if (!__grouping.empty()) {
    __insert_grouping(__str, __group_pos,
                      __grouping, __sep, '+', '-', 0);
  }

  return __copy_float_and_fill(__CONST_CAST(char*, __str.data()), 
                               __CONST_CAST(char*, __str.data()) + __str.size(), __oi,
                               __f.flags(), __f.width(0), __fill, '+', '-');
}

num_put<Pt::Char, ostreambuf_iterator<Pt::Char> >::iter_type
num_put<Pt::Char, ostreambuf_iterator<Pt::Char> >::do_put(iter_type s, ios_base& f, char_type fill, long double val) const
{
    putFloat(s, val, f.flags(), f.width(0), fill, f.precision());
    return s;
}

_OutputIter _S_do_put(_OutputIter __s, bool  __intl, ios_base&  __str,
                      _CharT __fill, const _Str& __digits, bool __check_digits,
                      _Str_Type * /*__dummy*/) {
  typedef _CharT char_type;
  typedef _Str_Type string_type;
  typedef ctype<char_type>             _Ctype;
  typedef moneypunct<char_type, false> _Punct;
  typedef moneypunct<char_type, true>  _Punct_intl;

  locale __loc = __str.getloc();
  const _Ctype&      __c_type     = use_facet<_Ctype>(__loc) ;
  const _Punct&      __punct      = use_facet<_Punct>(__loc) ;
  const _Punct_intl& __punct_intl = use_facet<_Punct_intl>(__loc) ;

  // some special characters
  char_type __minus = __c_type.widen('-');
  char_type __plus  = __c_type.widen('+');
  char_type __space = __c_type.widen(' ');
  char_type __zero  = __c_type.widen('0');
  char_type __point = __intl ? __punct_intl.decimal_point()
                             : __punct.decimal_point();

  char_type __sep = __intl ? __punct_intl.thousands_sep()
                           : __punct.thousands_sep();

  string __grouping = __intl ? __punct_intl.grouping()
                             : __punct.grouping();

  int __frac_digits      = __intl ? __punct_intl.frac_digits() 
                                  : __punct.frac_digits();

  string_type __curr_sym = __intl ? __punct_intl.curr_symbol() 
                                  : __punct.curr_symbol();

  // if there are no digits we are going to return __s.  If there
  // are digits, but not enough to fill the frac_digits, we are
  // going to add zeros.  I don't know whether this is right or
  // not.
  if (__digits.empty()) 
    return __s;

  typename string_type::const_iterator __digits_first = __digits.begin();
  typename string_type::const_iterator __digits_last  = __digits.end();

  bool __is_negative = *__digits_first == __minus;
  if (__is_negative)
    ++__digits_first;

  string_type __sign = __intl ? __is_negative ? __punct_intl.negative_sign()
                                              : __punct_intl.positive_sign()
                              : __is_negative ? __punct.negative_sign()
                                              : __punct.positive_sign();
  if (__check_digits) {
    typename string_type::const_iterator __cp = __digits_first;
    while (__cp != __digits_last && __c_type.is(ctype_base::digit, *__cp))
      ++__cp;
    if (__cp == __digits_first)
      return __s;
    __digits_last = __cp;
  }

  // If grouping is required, we make a copy of __digits and
  // insert the grouping.

  _STLP_BASIC_IOSTRING(char_type) __new_digits;
  if (!__grouping.empty()) {
    __new_digits.assign(__digits_first, __digits_last);
    __insert_grouping(__new_digits,
                      __new_digits.size() - __frac_digits,
                      __grouping,
                      __sep, __plus, __minus, 0);
    __digits_first = __new_digits.begin(); // <<--
    __digits_last  = __new_digits.end();   // <<--
  }

  // Determine the amount of padding required, if any.  
  streamsize __width = __str.width();

#if defined(_STLP_DEBUG) && (defined(__HP_aCC) && (__HP_aCC <= 1))
  size_t __value_length = operator -(__digits_last, __digits_first);
#else
  size_t __value_length = __digits_last - __digits_first;
#endif

  size_t __length = __value_length + __sign.size();

  if (__frac_digits != 0)
    ++__length;

  bool __generate_curr = (__str.flags() & ios_base::showbase) !=0;
  if (__generate_curr)
    __length += __curr_sym.size();
  money_base::pattern __format = __intl ? (__is_negative ? __punct_intl.neg_format()
                                                         : __punct_intl.pos_format())
                                        : (__is_negative ? __punct.neg_format()
                                                         : __punct.pos_format());
  {
    //For the moment the following is commented for decoding reason.
    //No reason to add a space last if the money symbol do not have to be display
    //if (__format.field[3] == (char) money_base::symbol && !__generate_curr) {
//.........这里部分代码省略.........