std::money_get

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Localizations library
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Facet category base classes
ctype facets
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collate facets
time facets
monetary facets
money_get
messages facets
Character classification and conversion
Character classification
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(C++11/17*)
(C++11/17*)
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(C++11/17*)
(C++11/17*)    
(C++11/17*)
C locale
 
 
Defined in header <locale>
template<

    class CharT,
    class InputIt = std::istreambuf_iterator<CharT>

> class money_get;

Class template std::money_get encapsulates the rules for parsing monetary values from character streams. The standard I/O manipulator std::get_money uses the std::money_get facet of the I/O stream's locale.

cpp/locale/locale/facetstd-money get-inheritance.svg

Inheritance diagram

If a std::money_get specialization is not guaranteed to be provided by the standard library (see below), the behaviors of its get() and do_get() are not guaranteed as specified.

Specializations

The standard library is guaranteed to provide the following specializations (they are required to be implemented by any locale object):

Defined in header <locale>
std::money_get<char> parses narrow string representations of monetary values
std::money_get<wchar_t> parses wide string representations of monetary values

In addition, the standard library is also guaranteed to provide every specialization that satisfies the following type requirements:

  • CharT is one of
    • char,
    • wchar_t, and
    • any other implementation-defined character type that meets the requirements for a character on which any of the iostream components can be instantiated; and
  • InputIt must meet the requirements of LegacyInputIterator.

Member types

Member type Definition
char_type CharT
string_type std::basic_string<CharT>
iter_type InputIt

Member functions

constructs a new money_get facet
(public member function)
destructs a money_get facet
(protected member function)
invokes do_get
(public member function)

Protected member functions

[virtual]
parses a monetary value from an input stream
(virtual protected member function)

Member objects

static std::locale::id id
id of the locale
(public member object)

Example

#include <iostream>
#include <sstream>
#include <locale>
#include <iomanip>
#include <iterator>
 
int main()
{
    std::string str = "$1.11 $2.22 $3.33";
    std::cout << std::fixed << std::setprecision(2);
 
    std::cout << '"' << str << "\" parsed with the I/O manipulator: ";
    std::istringstream s1(str);
    s1.imbue(std::locale("en_US.UTF-8"));
 
    long double val;
    while (s1 >> std::get_money(val))
        std::cout << val / 100 << ' ';
    std::cout << '\n';
 
    str = "USD  1,234.56";
    std::cout << '"' << str << "\" parsed with the facet directly: ";
    std::istringstream s2(str);
    s2.imbue(std::locale("en_US.UTF-8"));
 
    auto& f = std::use_facet<std::money_get<char>>(s2.getloc());
    std::ios_base::iostate err;
    std::istreambuf_iterator<char> beg(s2), end;
    f.get(beg, end, true, s2, err, val);
 
    std::cout << val / 100 << '\n';
}

Output:

"$1.11 $2.22 $3.33" parsed with the I/O manipulator: 1.11 2.22 3.33
"USD  1,234.56" parsed with the facet directly: 1234.56

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR Applied to Behavior as published Correct behavior
LWG 427 C++98 money_get could accept any CharT that meets
the requirements for a character on which any
of the iostream components can be instantiated
only guarantees to accept
char and wchar_t, other types
are implementation-defined

See also

defines monetary formatting parameters used by std::money_get and std::money_put
(class template)
formats a monetary value for output as a character sequence
(class template)
(C++11)
parses a monetary value
(function template)