do_get

static const char src[] = "0123456789-";
CharT atoms[sizeof(src)];
ct.widen(src, src + sizeof(src) - 1, atoms);
for (int i = 0; i < n; ++i)
buf2[i] = src[find(atoms, atoms+sizeof(src), buf1[i]) - atoms];
buf2[n] = 0;
sscanf(buf2, "%Lf", &units);

#include <iostream>
#include <sstream>
#include <locale>
 
void demo_money_get(std::locale loc, const std::string& input)
{
    std::istringstream str(input);
    str.imbue(loc);
    long double units;
// note, the following can be written simple with std::get_money(units)
    std::ios_base::iostate err = std::ios_base::goodbit;
    std::istreambuf_iterator<char> ret =
        std::use_facet<std::money_get<char>>(loc).get(
                 std::istreambuf_iterator<char>(str),
                 std::istreambuf_iterator<char>(),
                 false, str, err, units);
    str.setstate(err);
    if(str) {
        std::cout << "Successfully parsed '" << str.str() << "' as "
                  << units/100 << " units\n";
        if(ret != std::istreambuf_iterator<char>()) {
            std::cout << "Remaining content: '";
            std::copy(ret, std::istreambuf_iterator<char>(),
                           std::ostreambuf_iterator<char>(std::cout));
            std::cout << "'\n";
        } else {
            std::cout << "The input was fully consumed\n";
        }
    } else {
            std::cout << "Parse failed. Unparsed string: '";
            std::copy(ret, std::istreambuf_iterator<char>(),
                           std::ostreambuf_iterator<char>(std::cout));
            std::cout << "'\n";
    }
}
 
int main()
{
    demo_money_get(std::locale("en_US.utf8"), "-$5.12 abc");
    demo_money_get(std::locale("ms_MY.utf8"), "(RM5.12) def");
}

Successfully parsed '-$5.12 abc' as -5.12 units
Remaining content: ' abc'
Successfully parsed '(RM5.12) def' as -5.12 units
Remaining content: ' def'

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