Date

glib.date.Date is a struct for calendrical calculations.

The glib.date.Date data structure represents a day between January 1, Year 1, and sometime a few thousand years in the future (right now it will go to the year 65535 or so, but glib.date.Date.setParse only parses up to the year 8000 or so - just count on "a few thousand"). glib.date.Date is meant to represent everyday dates, not astronomical dates or historical dates or ISO timestamps or the like. It extrapolates the current Gregorian calendar forward and backward in time; there is no attempt to change the calendar to match time periods or locations. glib.date.Date does not store time information; it represents a day.

The glib.date.Date implementation has several nice features; it is only a 64-bit struct, so storing large numbers of dates is very efficient. It can keep both a Julian and day-month-year representation of the date, since some calculations are much easier with one representation or the other. A Julian representation is simply a count of days since some fixed day in the past; for #GDate the fixed day is January 1, 1 AD. ("Julian" dates in the #GDate API aren't really Julian dates in the technical sense; technically, Julian dates count from the start of the Julian period, Jan 1, 4713 BC).

glib.date.Date is simple to use. First you need a "blank" date; you can get a dynamically allocated date from glib.date.Date.new_, or you can declare an automatic variable or array and initialize it by calling glib.date.Date.clear. A cleared date is safe; it's safe to call glib.date.Date.setDmy and the other mutator functions to initialize the value of a cleared date. However, a cleared date is initially invalid, meaning that it doesn't represent a day that exists. It is undefined to call any of the date calculation routines on an invalid date. If you obtain a date from a user or other unpredictable source, you should check its validity with the glib.date.Date.valid predicate. glib.date.Date.valid is also used to check for errors with glib.date.Date.setParse and other functions that can fail. Dates can be invalidated by calling glib.date.Date.clear again.

It is very important to use the API to access the glib.date.Date struct. Often only the day-month-year or only the Julian representation is valid. Sometimes neither is valid. Use the API.

GLib also features glib.date_time.DateTime which represents a precise time.

class Date : Boxed {}

Constructors

this
this()

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

Members

Functions

addDays
void addDays(uint nDays)

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

addMonths
void addMonths(uint nMonths)

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.

addYears
void addYears(uint nYears)

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.

clamp
void clamp(glib.date.Date minDate, glib.date.Date maxDate)

If date is prior to min_date, sets date equal to min_date. If date falls after max_date, sets date equal to max_date. Otherwise, date is unchanged. Either of min_date and max_date may be null. All non-null dates must be valid.

clear
void clear(uint nDates)

Initializes one or more #GDate structs to a safe 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 glib.date.Date.valid.

compare
int compare(glib.date.Date rhs)

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

copy
glib.date.Date copy()

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

daysBetween
int daysBetween(glib.date.Date date2)

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

getDay
glib.types.DateDay getDay()

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

getDayOfYear
uint getDayOfYear()

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

getIso8601WeekOfYear
uint getIso8601WeekOfYear()

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

getJulian
uint getJulian()

Returns the Julian day or "serial number" of the #GDate. 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.

getMondayWeekOfYear
uint getMondayWeekOfYear()

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.

getMonth
glib.types.DateMonth getMonth()

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

getSundayWeekOfYear
uint getSundayWeekOfYear()

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.

getWeekday
glib.types.DateWeekday getWeekday()

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

getYear
glib.types.DateYear getYear()

Returns the year of a #GDate. The date must be valid.

isFirstOfMonth
bool isFirstOfMonth()

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

isLastOfMonth
bool isLastOfMonth()

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

order
void order(glib.date.Date date2)

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

setDay
void setDay(glib.types.DateDay day)

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

setDmy
void setDmy(glib.types.DateDay day, glib.types.DateMonth month, glib.types.DateYear y)

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

setJulian
void setJulian(uint julianDate)

Sets the value of a #GDate from a Julian day number.

setMonth
void setMonth(glib.types.DateMonth month)

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

setParse
void setParse(string str)

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 glib.date.Date.valid to see whether the parsing succeeded.

setTime
void setTime(glib.types.Time time)

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

setTimeT
void setTimeT(long timet)

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.

setTimeVal
void setTimeVal(glib.time_val.TimeVal timeval)

Sets the value of a date from a #GTimeVal value. Note that the tv_usec member is ignored, because #GDate can't make use of the additional precision.

setYear
void setYear(glib.types.DateYear year)

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

subtractDays
void subtractDays(uint nDays)

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.

subtractMonths
void subtractMonths(uint nMonths)

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.

subtractYears
void subtractYears(uint nYears)

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.

toStructTm
void toStructTm(void* tm)

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

valid
bool valid()

Returns true if the #GDate represents an existing day. The date must not contain garbage; it should have been initialized with glib.date.Date.clear if it wasn't allocated by one of the glib.date.Date.new_ variants.

Static functions

getDaysInMonth
ubyte getDaysInMonth(glib.types.DateMonth month, glib.types.DateYear year)

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

getMondayWeeksInYear
ubyte getMondayWeeksInYear(glib.types.DateYear year)

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.)

getSundayWeeksInYear
ubyte getSundayWeeksInYear(glib.types.DateYear 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.)

isLeapYear
bool isLeapYear(glib.types.DateYear year)

Returns true if the year is a leap year.

newDmy
glib.date.Date newDmy(glib.types.DateDay day, glib.types.DateMonth month, glib.types.DateYear year)

Create a new #GDate representing the given day-month-year triplet.

newJulian
glib.date.Date newJulian(uint julianDay)

Create a new #GDate representing the given Julian date.

strftime
size_t strftime(string s, size_t slen, string format, glib.date.Date date)

Generates a printed representation of the date, in a localesetlocale-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.

validDay
bool validDay(glib.types.DateDay day)

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

validDmy
bool validDmy(glib.types.DateDay day, glib.types.DateMonth month, glib.types.DateYear year)

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

validJulian
bool validJulian(uint julianDate)

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

validMonth
bool validMonth(glib.types.DateMonth month)

Returns true if the month value is valid. The 12 #GDateMonth enumeration values are the only valid months.

validWeekday
bool validWeekday(glib.types.DateWeekday weekday)

Returns true if the weekday is valid. The seven #GDateWeekday enumeration values are the only valid weekdays.

validYear
bool validYear(glib.types.DateYear year)

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

Inherited Members

From Boxed

cInstancePtr
void* cInstancePtr;

Pointer to the C boxed value

getType
GType getType()

Get the GType of this boxed type.

gType
GType gType [@property getter]

Boxed GType property.

self
Boxed self()

Convenience method to return this cast to a type. For use in D with statements.

copy_
void* copy_()

Make a copy of the wrapped C boxed data.

boxedCopy
void* boxedCopy(void* cBoxed)

Copy a C boxed value using g_boxed_copy.

boxedFree
void boxedFree(void* cBoxed)

Free a C boxed value using g_boxed_free.