| Copyright | (C) 2017 Jason Johnson |
|---|---|
| License | BSD-style (see the file LICENSE) |
| Maintainer | Jason Johnson <jason.johnson.081@gmail.com> |
| Stability | experimental |
| Portability | POSIX, Windows |
| Safe Haskell | Safe-Inferred |
| Language | Haskell2010 |
Data.HodaTime.CalendarDate
Description
This is the module for CalendarDate. A CalendarDate represents a date within the calendar system that is part of its type. It has no reference to a particular time zone or time of day.
Construction
To construct one of these types, see the Calendar module you wish to construct the date in (typically Data.HodaTime.Calendar.Gregorian)
Synopsis
- data DayNth
- = FourthToLast
- | ThirdToLast
- | SecondToLast
- | Last
- | First
- | Second
- | Third
- | Fourth
- | Fifth
- type Year = Int
- type WeekNumber = Int
- type DayOfMonth = Int
- type CalendarDate cal = Date cal
- class HasDate d where
- type DoW d
- type MoY d
- day :: Functor f => (DayOfMonth -> f DayOfMonth) -> d -> f d
- month :: d -> MoY d
- monthl :: Functor f => (Int -> f Int) -> d -> f d
- year :: Functor f => (Year -> f Year) -> d -> f d
- dayOfWeek :: d -> DoW d
- next :: Int -> DoW d -> d -> d
- previous :: Int -> DoW d -> d -> d
- yearMonthDay :: d -> (Year, MoY d, DayOfMonth)
Documentation
Used by several smart constructors to chose a day relative to the start or end of the month.
Constructors
| FourthToLast | |
| ThirdToLast | |
| SecondToLast | |
| Last | |
| First | |
| Second | |
| Third | |
| Fourth | |
| Fifth |
type WeekNumber = Int Source #
type DayOfMonth = Int Source #
type CalendarDate cal = Date cal Source #
A calendar date in the calendar system cal. This is a public synonym for the per-calendar representation
Date: each calendar defines its own data instance Date cal (see IsCalendar), so unrelated calendars
(e.g. Gregorian and Hebrew) need share nothing in how a date is stored.
class HasDate d where Source #
Methods
day :: Functor f => (DayOfMonth -> f DayOfMonth) -> d -> f d Source #
Lens for the day component of a HasDate. Please note that days are not clamped: if you add e.g. 400 days then the month and year will roll
Accessor for the Month component of a HasDate.
monthl :: Functor f => (Int -> f Int) -> d -> f d Source #
Lens for interacting with the month component of a HasDate. Please note that we convert the month to an Int so meaningful math can be done on it. Also
please note that the day will be unaffected except in the case of "end of month" days which may clamp. Note that this clamping will only occur as a final step,
so that
>>>modify monthl (+ 2) <$> Gregorian.calendarDate 31 January 2000Just (CalendarDate 31 March 2000)
and not 29th of March as would happen with some libraries.
year :: Functor f => (Year -> f Year) -> d -> f d Source #
Lens for the year component of a HasDate. Please note that the rest of the date is left as is, with two exceptions: Feb 29 will clamp to 28 in a non-leapyear
and if the new year is earlier than the earliest supported year it will clamp back to that year
dayOfWeek :: d -> DoW d Source #
Accessor for the Day of the week enum of a HasDate, for example:
>>>dayOfWeek . fromJust $ Gregorian.calendarDate 31 January 2000Monday
next :: Int -> DoW d -> d -> d Source #
Returns a HasDate shifted to the nth next Day of Week from the current HasDate, for example:
>>>next 1 Monday . fromJust $ Gregorian.calendarDate 31 January 2000CalendarDate 7 February 2000
previous :: Int -> DoW d -> d -> d Source #
Returns a HasDate shifted to the nth previous Day of Week from the current HasDate, for example:
>>>previous 1 Monday . fromJust $ Gregorian.calendarDate 31 January 2000CalendarDate 24 January 2000
yearMonthDay :: d -> (Year, MoY d, DayOfMonth) Source #
Access the year, month and day-of-month components together in a single call, returned as a
(year, month, day) tuple.
This is purely an access optimization for code that needs more than one date component at once. Reading the
components individually with year, month and day is perfectly correct, but for a packed representation
(such as the Gregorian Date, which stores a cycle/century/day-in-century triple) each of those accessors
independently decodes the stored value, so asking for all three separately decodes it three times.
yearMonthDay decodes once and hands back every component, which is noticeably cheaper on hot paths (for
example date formatting). For representations that already store the components separately (such as the Julian
Date) there is nothing to decode and this is simply the three field reads, so it is never slower than the
individual accessors and callers can use it unconditionally.