Memory-managed wrapper type.

Construct a Date struct initialized to zero.

A convenience alias for Nothing :: Maybe Date.

Increments a date some number of days. To move forward by weeks, add weeks*7 days. The date must be valid.

Increments a date by some number of months. If the day of the month is greater than 28, this routine may change the day of the month (because the destination month may not have the current day in it). The date must be valid.

Increments a date by some number of years. If the date is February 29, and the destination year is not a leap year, the date will be changed to February 28. The date must be valid.

If date is prior to minDate, sets date equal to minDate. If date falls after maxDate, sets date equal to maxDate. Otherwise, date is unchanged. Either of minDate and maxDate may be Nothing. All non-Nothing dates must be valid.

Initializes one or more Date structs to a sane but invalid state. The cleared dates will not represent an existing date, but will not contain garbage. Useful to init a date declared on the stack. Validity can be tested with dateValid.

qsort()-style comparison function for dates. Both dates must be valid.

Copies a GDate to a newly-allocated GDate. If the input was invalid (as determined by dateValid), the invalid state will be copied as is into the new object.

Since: 2.56

Computes the number of days between two dates. If date2 is prior to date1, the returned value is negative. Both dates must be valid.

Frees a Date returned from dateNew.

Returns the day of the month. The date must be valid.

Returns the day of the year, where Jan 1 is the first day of the year. The date must be valid.

Returns the number of days in a month, taking leap years into account.

Returns the week of the year, where weeks are interpreted according to ISO 8601.

Since: 2.6

Returns the Julian day or "serial number" of the Date. The Julian day is simply the number of days since January 1, Year 1; i.e., January 1, Year 1 is Julian day 1; January 2, Year 1 is Julian day 2, etc. The date must be valid.

Returns the week of the year, where weeks are understood to start on Monday. If the date is before the first Monday of the year, return 0. The date must be valid.

Returns the number of weeks in the year, where weeks are taken to start on Monday. Will be 52 or 53. The date must be valid. (Years always have 52 7-day periods, plus 1 or 2 extra days depending on whether it's a leap year. This function is basically telling you how many Mondays are in the year, i.e. there are 53 Mondays if one of the extra days happens to be a Monday.)

Returns the month of the year. The date must be valid.

Returns the week of the year during which this date falls, if weeks are understood to begin on Sunday. The date must be valid. Can return 0 if the day is before the first Sunday of the year.

Returns the number of weeks in the year, where weeks are taken to start on Sunday. Will be 52 or 53. The date must be valid. (Years always have 52 7-day periods, plus 1 or 2 extra days depending on whether it's a leap year. This function is basically telling you how many Sundays are in the year, i.e. there are 53 Sundays if one of the extra days happens to be a Sunday.)

Returns the day of the week for a Date. The date must be valid.

Returns the year of a Date. The date must be valid.

Returns True if the date is on the first of a month. The date must be valid.

Returns True if the date is the last day of the month. The date must be valid.

Returns True if the year is a leap year.

For the purposes of this function, leap year is every year divisible by 4 unless that year is divisible by 100. If it is divisible by 100 it would be a leap year only if that year is also divisible by 400.

Allocates a Date and initializes it to a sane state. The new date will be cleared (as if you'd called dateClear) but invalid (it won't represent an existing day). Free the return value with dateFree.

Like dateNew, but also sets the value of the date. Assuming the day-month-year triplet you pass in represents an existing day, the returned date will be valid.

Like dateNew, but also sets the value of the date. Assuming the Julian day number you pass in is valid (greater than 0, less than an unreasonably large number), the returned date will be valid.

Checks if date1 is less than or equal to date2, and swap the values if this is not the case.

Sets the day of the month for a Date. If the resulting day-month-year triplet is invalid, the date will be invalid.

Sets the value of a Date from a day, month, and year. The day-month-year triplet must be valid; if you aren't sure it is, call dateValidDmy to check before you set it.

Sets the value of a Date from a Julian day number.

Sets the month of the year for a Date. If the resulting day-month-year triplet is invalid, the date will be invalid.

Parses a user-inputted string str, and try to figure out what date it represents, taking the [current locale][setlocale] into account. If the string is successfully parsed, the date will be valid after the call. Otherwise, it will be invalid. You should check using dateValid to see whether the parsing succeeded.

This function is not appropriate for file formats and the like; it isn't very precise, and its exact behavior varies with the locale. It's intended to be a heuristic routine that guesses what the user means by a given string (and it does work pretty well in that capacity).

Sets the value of a date from a GTime value. The time to date conversion is done using the user's current timezone.

Sets the value of a date to the date corresponding to a time specified as a time_t. The time to date conversion is done using the user's current timezone.

To set the value of a date to the current day, you could write:

C code

time_t now = time (NULL);
if (now == (time_t) -1)
  // handle the error
g_date_set_time_t (date, now);

Since: 2.10

Sets the value of a date from a TimeVal value. Note that the tvUsec member is ignored, because Date can't make use of the additional precision.

The time to date conversion is done using the user's current timezone.

Since: 2.10

Sets the year for a Date. If the resulting day-month-year triplet is invalid, the date will be invalid.

Generates a printed representation of the date, in a [locale][setlocale]-specific way. Works just like the platform's C library strftime() function, but only accepts date-related formats; time-related formats give undefined results. Date must be valid. Unlike strftime() (which uses the locale encoding), works on a UTF-8 format string and stores a UTF-8 result.

This function does not provide any conversion specifiers in addition to those implemented by the platform's C library. For example, don't expect that using dateStrftime would make the %F provided by the C99 strftime() work on Windows where the C library only complies to C89.

Moves a date some number of days into the past. To move by weeks, just move by weeks*7 days. The date must be valid.

Moves a date some number of months into the past. If the current day of the month doesn't exist in the destination month, the day of the month may change. The date must be valid.

Moves a date some number of years into the past. If the current day doesn't exist in the destination year (i.e. it's February 29 and you move to a non-leap-year) then the day is changed to February 29. The date must be valid.

Fills in the date-related bits of a struct tm using the date value. Initializes the non-date parts with something sane but meaningless.

Returns True if the Date represents an existing day. The date must not contain garbage; it should have been initialized with dateClear if it wasn't allocated by one of the dateNew variants.

Returns True if the day of the month is valid (a day is valid if it's between 1 and 31 inclusive).

Returns True if the day-month-year triplet forms a valid, existing day in the range of days Date understands (Year 1 or later, no more than a few thousand years in the future).

Returns True if the Julian day is valid. Anything greater than zero is basically a valid Julian, though there is a 32-bit limit.

Returns True if the month value is valid. The 12 DateMonth enumeration values are the only valid months.

Returns True if the weekday is valid. The seven DateWeekday enumeration values are the only valid weekdays.

Returns True if the year is valid. Any year greater than 0 is valid, though there is a 16-bit limit to what Date will understand.

Get the value of the “day” field. When overloading is enabled, this is equivalent to

get date #day

Set the value of the “day” field. When overloading is enabled, this is equivalent to

set date [ #day := value ]

Get the value of the “dmy” field. When overloading is enabled, this is equivalent to

get date #dmy

Set the value of the “dmy” field. When overloading is enabled, this is equivalent to

set date [ #dmy := value ]

Get the value of the “julian” field. When overloading is enabled, this is equivalent to

get date #julian

Set the value of the “julian” field. When overloading is enabled, this is equivalent to

set date [ #julian := value ]

Get the value of the “julian_days” field. When overloading is enabled, this is equivalent to

get date #julianDays

Set the value of the “julian_days” field. When overloading is enabled, this is equivalent to

set date [ #julianDays := value ]

Get the value of the “month” field. When overloading is enabled, this is equivalent to

get date #month

Set the value of the “month” field. When overloading is enabled, this is equivalent to

set date [ #month := value ]

Get the value of the “year” field. When overloading is enabled, this is equivalent to

get date #year

Set the value of the “year” field. When overloading is enabled, this is equivalent to

set date [ #year := value ]