25 Localization library [localization]

25.4 Standard locale categories [locale.categories]

25.4.5 The time category [category.time]

25.4.5.1 Class template time_­get [locale.time.get]

25.4.5.1.2 time_­get virtual functions [locale.time.get.virtuals]

dateorder do_date_order() const;
Returns: An enumeration value indicating the preferred order of components for those date formats that are composed of day, month, and year.248
Returns no_­order if the date format specified by 'x' contains other variable components (e.g., Julian day, week number, week day).
iter_type do_get_time(iter_type s, iter_type end, ios_base& str, ios_base::iostate& err, tm* t) const;
Effects: Reads characters starting at s until it has extracted those struct tm members, and remaining format characters, used by time_­put<>​::​put to produce the format specified by "%H:%M:%S", or until it encounters an error or end of sequence.
Returns: An iterator pointing immediately beyond the last character recognized as possibly part of a valid time.
iter_type do_get_date(iter_type s, iter_type end, ios_base& str, ios_base::iostate& err, tm* t) const;
Effects: Reads characters starting at s until it has extracted those struct tm members and remaining format characters used by time_­put<>​::​put to produce one of the following formats, or until it encounters an error.
The format depends on the value returned by date_­order() as shown in Table 72.
Table 72do_­get_­date effects
date_­order()
Format
no_­order
"%m%d%y"
dmy
"%d%m%y"
mdy
"%m%d%y"
ymd
"%y%m%d"
ydm
"%y%d%m"
An implementation may also accept additional implementation-defined formats.
Returns: An iterator pointing immediately beyond the last character recognized as possibly part of a valid date.
iter_type do_get_weekday(iter_type s, iter_type end, ios_base& str, ios_base::iostate& err, tm* t) const; iter_type do_get_monthname(iter_type s, iter_type end, ios_base& str, ios_base::iostate& err, tm* t) const;
Effects: Reads characters starting at s until it has extracted the (perhaps abbreviated) name of a weekday or month.
If it finds an abbreviation that is followed by characters that could match a full name, it continues reading until it matches the full name or fails.
It sets the appropriate struct tm member accordingly.
Returns: An iterator pointing immediately beyond the last character recognized as part of a valid name.
iter_type do_get_year(iter_type s, iter_type end, ios_base& str, ios_base::iostate& err, tm* t) const;
Effects: Reads characters starting at s until it has extracted an unambiguous year identifier.
It is implementation-defined whether two-digit year numbers are accepted, and (if so) what century they are assumed to lie in.
Sets the t->tm_­year member accordingly.
Returns: An iterator pointing immediately beyond the last character recognized as part of a valid year identifier.
iter_type do_get(iter_type s, iter_type end, ios_base& f, ios_base::iostate& err, tm* t, char format, char modifier) const;
Requires: t shall point to an object.
Effects: The function starts by evaluating err = ios_­base​::​goodbit.
It then reads characters starting at s until it encounters an error, or until it has extracted and assigned those struct tm members, and any remaining format characters, corresponding to a conversion directive appropriate for the ISO/IEC 9945 function strptime, formed by concatenating '%', the modifier character, when non-NUL, and the format character.
When the concatenation fails to yield a complete valid directive the function leaves the object pointed to by t unchanged and evaluates err |= ios_­base​::​failbit.
When s == end evaluates to true after reading a character the function evaluates err |= ios_­base​::​eofbit.
For complex conversion directives such as %c, %x, or %X, or directives that involve the optional modifiers E or O, when the function is unable to unambiguously determine some or all struct tm members from the input sequence [s, end), it evaluates err |= ios_­base​::​eofbit.
In such cases the values of those struct tm members are unspecified and may be outside their valid range.
Remarks: It is unspecified whether multiple calls to do_­get() with the address of the same struct tm object will update the current contents of the object or simply overwrite its members.
Portable programs should zero out the object before invoking the function.
Returns: An iterator pointing immediately beyond the last character recognized as possibly part of a valid input sequence for the given format and modifier.
This function is intended as a convenience only, for common formats, and may return no_­order in valid locales.