std::numpunct::thousands_sep, do_thousands_sep

 

C++

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Localizations library

Locales and facets
locale
use_facet	has_facet
Character classification
isspace isblank (C++11) iscntrl isupper islower isalpha	isdigit ispunct isxdigit isalnum isprint isgraph
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toupper tolower	wstring_convert (C++11) wbuffer_convert (C++11)
Facet category base classes
ctype_base codecvt_base messages_base	time_base money_base
Facet categories
ctype ctype<char> codecvt collate messages time_get time_put	num_get num_put numpunct money_get money_put moneypunct
Locale-specific facets
ctype_byname ctype_byname<char> codecvt_byname messages_byname collate_byname	time_get_byname time_put_byname numpunct_byname moneypunct_byname
Code conversion facets
codecvt_utf8 (C++11) codecvt_utf16 (C++11)	codecvt_utf8_utf16 (C++11) codecvt_mode (C++11)
C locale
setlocale localeconv lconv	LC_ALL LC_COLLATE LC_CTYPE LC_MONETARY LC_NUMERIC LC_TIME

 

std::numpunct

Member functions

numpunct::numpunct

numpunct::~numpunct

numpunct::decimal_point numpunct::do_decimal_point

numpunct::thousands_sep numpunct::do_thousands_sep

numpunct::grouping numpunct::do_grouping

numpunct::truename numpunct::do_truename numpunct::falsename numpunct::do_falsename

 

Defined in header <locale>
public: char_type thousands_sep() const;	(1)
protected: char_type virtual do_thousands_sep() const;	(2)

1) Public member function, calls the member function do_thousands_sep of the most derived class.

2) Returns the character to be used as the separator between digit groups when parsing or formatting integers and integral parts of floating-point values.

Return value

The object of type char_type to use as the thousands separator. The standard specializations of std::numpunct return ’,’ and L’,’.

Example

run this code

#include <iostream>
#include <locale>
 
struct space_out : std::numpunct<char> {
    char do_thousands_sep()   const { return ' '; }  // separate with spaces
    std::string do_grouping() const { return "\1"; } // groups of 1 digit
};
 
int main()
{
    std::cout << "default locale: " << 12345678 << '\n';
    std::cout.imbue(std::locale(std::cout.getloc(), new space_out));
    std::cout << "locale with modified numpunct: " << 12345678 << '\n';
}

Output:

default locale: 12345678
locale with modified numpunct: 1 2 3 4 5 6 7 8

See also

do_grouping [virtual]	provides the numbers of digits between each pair of thousands separators (virtual protected member function)