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                       Standard C++ Library
             Copyright 1998, Rogue Wave Software, Inc.


NAME
     moneypunct, moneypunct_byname

      - Monetary punctuation facets.



SYNOPSIS
     #include <locale>
     class money_base;
     template <class charT, bool International = false>
     class moneypunct;



DESCRIPTION
     The moneypunct_facets include formatting specifications  and
     punctuation  character  for  monetary values. The moneypunct
     facet   is    used    with    the    "C"    locale,    while
     the_moneypunct_byname facet is used with named locales.

     The facet is  used  by  money_put_for  outputting  formatted
     representations  of  monetary  values  and  by_money_get for
     reading these strings back in.

     money_base includes a structure, pattern, that specifies the
     order of syntactic elements in a monetary value and enumera-
     tion values representing those elements. The pattern  struct
     includes  a simple array of characters, field. Each index in
     field is taken up by an  enumeration  value  indicating  the
     location  of a syntactic element. The enumeration values are
     described below:

     FORMAT FLAG    MEANING


     none           No grouping separator

     space          Use space for grouping separator

     symbol         Currency symbol

     sign           Sign of monetary value

     value          The monetary value itself

     The do_pos_format  and  do_neg_format  member  functions  of
     moneypunct both return the pattern type. See the description
     of these functions for further elaboration.



INTERFACE
     class money_base {
     public:
      enum part { none, space, symbol, sign, value };
      struct pattern { char field[4]; };
     };

     template <class charT, bool International = false>
     class moneypunct : public locale::facet, public money_base {
     public:
      typedef charT char_type;
      typedef basic_string<charT> string_type;
      explicit moneypunct(size_t = 0);
      charT        decimal_point() const;
      charT        thousands_sep() const;
      string       grouping()      const;
      string_type  curr_symbol()   const;
      string_type  positive_sign() const;
      string_type  negative_sign() const;
      int          frac_digits()   const;
      pattern      pos_format()    const;
      pattern      neg_format()    const;
      static locale::id id;
      static const bool intl = International;
     protected:
       ~moneypunct();  // virtual
      virtual charT        do_decimal_point() const;
      virtual charT        do_thousands_sep() const;
      virtual string       do_grouping()      const;
      virtual string_type  do_curr_symbol()   const;
      virtual string_type  do_positive_sign() const;
      virtual string_type  do_negative_sign() const;
      virtual int          do_frac_digits()   const;
      virtual pattern      do_pos_format()    const;
      virtual pattern      do_neg_format()    const;
     };

     template <class charT, bool Intl = false>
     class moneypunct_byname : public moneypunct<charT, Intl> {
     public:
      explicit moneypunct_byname(const char*, size_t = 0);
     protected:
       ~moneypunct_byname();  // virtual
      virtual charT        do_decimal_point() const;
      virtual charT        do_thousands_sep() const;
      virtual string       do_grouping()      const;
      virtual string_type  do_curr_symbol()   const;
      virtual string_type  do_positive_sign() const;
      virtual string_type  do_negative_sign() const;
      virtual int          do_frac_digits()   const;
      virtual pattern      do_pos_format()    const;
      virtual pattern      do_neg_format()    const;
     };



TYPES
     char_type


        Type of character the facet is instantiated on.



     string_type


        Type of character string returned by member functions.



CONSTRUCTORS
     explicit moneypunct(size_t refs = 0)


        Constructs a moneypunct facet. If the refs argument is 0,
        then  destruction  of  the  object  is  delegated  to the
        locale, or locales, containing it. This allows  the  user
        to  ignore lifetime management issues. On the other hand,
        if refs is 1, then the object must be explicitly deleted;
        the  locale  does not do so. In this case, the object can
        be maintained across the lifetime of multiple locales.



     explicit moneypunct_byname(const char* name,
                                 size_t refs = 0);


        Constructs a  moneypunct_byname  facet.  Uses  the  named
        locale  specified by the name argument. The refs argument
        serves the same purpose as it  does  for  the  moneypunct
        constructor.

DESTRUCTORS
     ~moneypunct();  // virtual and protected


        Destroys the facet.



STATIC MEMBERS
     static locale::id id;


        Unique identifier for this type of facet.



     static const bool intl = Intl;


        true for international representation, false otherwise.



PUBLIC MEMBER FUNCTIONS
     The public members of the  moneypunct  and_moneypunct_byname
     facets  include an interface to protected members. Each pub-
     lic member xxx has a corresponding virtual protected  member
     do_xxx.  All  work  is delegated to these protected members.
     For instance, the long version of the  public  decimal_point
     function simply calls its protected cousin do_decimal_point.


     string_type  curr_symbol()   const;
     charT        decimal_point() const;
     int          frac_digits()   const;
     string       grouping()      const;
     pattern      neg_format()    const;
     string_type  negative_sign() const;
     pattern      pos_format()    const;
     string_type  positive_sign() const;
     charT        thousands_sep() const;


        Each  public  member  function  xxx  simply   calls   the
        corresponding protected do_xxx function.



PROTECTED MEMBER FUNCTIONS
     virtual string_type
     do_curr_symbol()   const;


        Returns a string to use as the currency symbol.



     virtual charT
     do_decimal_point() const;


        Returns the radix separator to use if  fractional  digits
        are allowed (see do_frac_digits).



     virtual int
     do_frac_digits()   const;


        Returns the number of digits in the  fractional  part  of
        the monetary representation.



     virtual string
     do_grouping()      const;


        Returns a string in which each character is  used  as  an
        integer value to represent the number of digits in a par-
        ticular grouping, starting with the  rightmost  group.  A
        group  is  simply  the digits between adjacent thousands'
        separators. Each group at a position larger than the size
        of  the string gets the same value as the last element in
        the string. If a value is less than or equal to zero,  or
        equal  to CHAR_MAX, then the size of that group is unlim-
        ited.   moneypunct returns an empty string, indicating no
        grouping.



     virtual string_type
     do_negative_sign() const;


        A string to use as the negative sign. The first character
        of this string is placed in the position indicated by the
        format pattern (see do_neg_format); the rest of the char-
        acters,  if  any, are placed after all other parts of the
        monetary value.



     virtual pattern
     do_neg_format()    const;
     virtual pattern
     do_pos_format()    const;


        Returns a pattern object specifying the location  of  the
        various  syntactic elements in a monetary representation.
        The enumeration values symbol,  sign,  and  value  appear
        exactly once in this pattern, with the remaining location
        taken by either none or space. none  never  occupies  the
        first  position  in  the pattern and space never occupies
        the first or the last  position.  Beyond  these  restric-
        tions,  elements  may  appear  in  any  order. moneypunct
        returns {symbol, sign, none, value}.



     virtual string_type
     do_positive_sign() const;


        A string to use as the positive sign. The first character
        of this string is placed in the position indicated by the
        format pattern (see do_pos_format); the rest of the char-
        acters,  if  any, are placed after all other parts of the
        monetary value.



     virtual charT
     do_thousands_sep() const;


        Returns the grouping separator  if  grouping  is  allowed
        (see do_grouping).



EXAMPLE
     //
     // moneypun.cpp
     //

     #include <string>

     #include <iostream>

     int main ()
     {
      using namespace std;

      locale loc;

       // Get a moneypunct facet
      const moneypunct<char,false>& mp =
     #ifndef _RWSTD_NO_TEMPLATE_ON_RETURN_TYPE
      use_facet<moneypunct<char,false> >(loc);
     #else
      use_facet(loc,(moneypunct<char,false>*)0);
     #endif

      cout << "Decimal point        = "
            << mp.decimal_point() << endl;
      cout << "Thousands separator  = "
            << mp.thousands_sep() << endl;
      cout << "Currency symbol      = "
            << mp.curr_symbol() << endl;
      cout << "Negative Sign        = "
            << mp.negative_sign() << endl;
      cout << "Digits after decimal = "
            << mp.frac_digits() << endl;

      return 0;
     }



SEE ALSO
     locale, facets, money_put, money_get

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