Standard C++	Library
 		 Copyright 1996, Rogue Wave Software, Inc.

 NAME

   numpunct, numpunct_byname - Numeric punctuation facet.

 SYNOPSIS

   #include <locale>
   template <class charT>  class	numpunct;
   template <class charT>  class	numpunct_byname;

 DESCRIPTION

   The numpunct<charT> facet specifies numeric punctuation.  This
   template provides punctuation based on	the "C"	locale,	while
   the numpunct_byname facet	provides the same facilities for named
   locales.

   Both num_put and num_get make	use of this facet.

 INTERFACE

   template <class charT>
   class	numpunct : public locale::facet	{
   public:
    typedef charT	       char_type;
    typedef basic_string<charT> string_type;
    explicit numpunct(size_t refs = 0);
    char_type	decimal_point()	  const;
    char_type	thousands_sep()	  const;
    string	grouping()	  const;
    string_type	truename()	  const;
    string_type	falsename()	  const;
    static locale::id id;
   protected:
     ~numpunct();  // virtual
    virtual char_type	do_decimal_point() const;
    virtual char_type	do_thousands_sep() const;
    virtual string	do_grouping()	   const;
    virtual string_type	do_truename()	   const;  // for bool
    virtual string_type	do_falsename()	   const;  // for bool
   };

   template <class charT>
   class	numpunct_byname	: public numpunct<charT> {
   public:
    explicit numpunct_byname(const char*, size_t	refs = 0);
   protected:
     ~numpunct_byname();	 // virtual
    virtual char_type	do_decimal_point() const;
    virtual char_type	do_thousands_sep() const;
    virtual string	do_grouping()	   const;
    virtual string_type	do_truename()	   const;  // for bool
    virtual string_type	do_falsename()	   const;  // for bool
   };

 TYPES

   char_type
      Type of character upon which the facet is instantiated.

   string_type

      Type of character string returned by member functions.

 CONSTRUCTORS AND DESTRUCTORS

   explicit numpunct(size_t refs	= 0)
      Construct a numpunct 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 had, if refs  is 1	then
      the object	must be	explicitly deleted; the locale will not do
      so.  In	this case, the object can be maintained across the
      lifetime of multiple locales.

   explicit numpunct_byname(const char* name, size_t refs = 0);
      Construct a numpunct_byname facet.	 Use the named locale
      specified	by the name argument.	 The refs argument serves the
      same purpose as it does for the numpunct constructor.

   ~numpunct();	// virtual and protected
   ~numpunct_byname();  // virtual and protected

      Destroy the facet

 FACET ID

   static locale::id id;

      Unique identifier for this	type of	facet.

 PUBLIC MEMBER FUNCTIONS

   The public members of	the numpunct facet provide an interface	to
   protected members.  Each public	member xxx has a corresponding
   virtual protected member do_xxx.  All work is delagated	to
   these protected members.   For instance, the	long version of	the
   public grouping function simply calls its protected cousin
   do_grouping.

   char_type    decimal_point()	 const;
   string_type  falsename()	 const;
   string       grouping()	 const;
   char_type    thousands_sep()	 const;
   string_type  truename()	 const;

      Each of these public member functions xxx simply call the
      corresponding protected do_xxx function.

 PROTECTED MEMBER FUNCTIONS

   virtual char_type
   do_decimal_point() const;

      Returns the decimal radix separator .  numpunct returns '.'.

   virtual string_type
   do_falsename()     const;  //	for bool
   virtual string_type
   do_truename()	     const;  //	for bool

      Returns a string representing the name of the boolean values true
      and false respectively.  numpunct returns  "true" and
      "false".

   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 particular 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 unlimited.  numpunct returns an empty string,
      indicating no grouping.

   virtual char_type
   do_thousands_sep() const;

      Returns the decimal digit group seperator.	 numpunct returns ','.

 EXAMPLE

   //
   // numpunct.cpp
   //

   #include <iostream>

   int main ()
   {
    using namespace std;
    locale loc;

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

    cout	<< "Decimal point	= "
 	 << np.decimal_point() << endl;
    cout	<< "Thousands seperator	= "
 	 << np.thousands_sep() << endl;
    cout	<< "True name		= "
 	 << np.truename() << endl;
    cout	<< "False name		= "
 	 << np.falsename() << endl;

    return 0;
   }

 SEE ALSO

   locale, facets, num_put, num_get, ctype

 STANDARDS CONFORMANCE
   ANSI X3J16/ISO WG21 Joint C++	Committee