# std::time_get<CharT,InputIt>::get_year, std::time_get<CharT,InputIt>::do_get_year

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< cpp‎ | locale‎ | time get

Defined in header `<locale>` |  |
public: iter_type do_get_year( iter_type s, iter_type end, std::ios_base& str, std::ios_base::iostate& err, std::tm* t) const; | (1) |
protected: virtual iter_type do_get_year( iter_type s, iter_type end, std::ios_base& str, std::ios_base::iostate& err, std::tm* t) const; | (2) |

1) public member function, calls the protected virtual member function `do_get_year` of the most derived class.
2) Reads successive characters from the sequence `[beg, end)` and parses out the year using some implementation-defined format. Depending on the locale, two-digit years may be accepted, and it is implementation-defined which century they belong to.

The parsed year is stored in the std::tm structure field t->tm_year.

If the end iterator is reached before a valid date is read, the function sets std::ios_base::eofbit in `err`. If a parsing error is encountered, the function sets std::ios_base::failbit in `err`.

### Parameters

beg | - | iterator designating the start of the sequence to parse
end | - | one past the end iterator for the sequence to parse
str | - | a stream object that this function uses to obtain locale facets when needed, e.g. std::ctype to skip whitespace or std::collate to compare strings
err | - | stream error flags object that is modified by this function to indicate errors
t | - | pointer to the std::tm object that will hold the result of this function call

### Return value

Iterator pointing one past the last character in `[beg, end)` that was recognized as a part of a valid year.

### Notes

For two-digit input values, many implementations use the same parsing rules as the conversion specifier '%y' as used by std::get_time, std::time_get::get(), and the POSIX function `strptime()`: two-digit integer is expected, the values in the range [69,99] results in values 1969 to 1999, range [00,68] results in 2000-2068. Four-digit inputs are typically accepted as-is.

If a parsing error is encountered, most implementations of this function leave `*t` unmodified.

### Example

Run this code

    #include <iostream>
    #include <locale>
    #include <sstream>
    #include <iterator>

    void try_get_year(const std::string& s)
    {
        std::cout << "Parsing the year out of '" << s <<
                     "' in the locale " << std::locale().name() << '\n';
        std::istringstream str(s);
        std::ios_base::iostate err = std::ios_base::goodbit;

        std::tm t;
        std::istreambuf_iterator<char> ret =
            std::use_facet<std::time_get<char>>(str.getloc()).get_year(
                {str}, {}, str, err, &t
            );
        str.setstate(err);
        std::istreambuf_iterator<char> last{};
        if (str) {
            std::cout << "Successfully parsed, year is " << 1900 + t.tm_year;
            if (ret != last) {
                std::cout << " Remaining content: ";
                std::copy(ret, last, std::ostreambuf_iterator<char>(std::cout));
            } else {
                std::cout << " the input was fully consumed";
            }
        } else {
            std::cout << "Parse failed. Unparsed string: ";
            std::copy(ret, last, std::ostreambuf_iterator<char>(std::cout));
        }
        std::cout << '\n';
    }

    int main()
    {
        std::locale::global(std::locale("en_US.utf8"));
        try_get_year("13");
        try_get_year("2013");

        std::locale::global(std::locale("ja_JP.utf8"));
        try_get_year("2013年");
    }

Possible output:

    Parsing the year out of '13' in the locale en_US.utf8
    Successfully parsed, year is 2013 the input was fully consumed
    Parsing the year out of '2013' in the locale en_US.utf8
    Successfully parsed, year is 2013 the input was fully consumed
    Parsing the year out of '2013年' in the locale ja_JP.utf8
    Successfully parsed, year is 2013 Remaining content: 年

### See also

get_time (C++11) | parses a date/time value of specified format (function template)

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