Data.Time.Format

Safe Haskell	Safe-Inferred
Language	Haskell2010

UNIX-style formatting

class FormatTime t Source

formatTime :: FormatTime t => TimeLocale -> String -> t -> String Source

Substitute various time-related information for each %-code in the string, as per formatCharacter.

The general form is %<modifier><width><alternate><specifier>, where <modifier>, <width>, and <alternate> are optional.

<modifier>

glibc-style modifiers can be used before the specifier (here marked as z):

%-z

no padding

%_z

pad with spaces

%0z

pad with zeros

%^z

convert to upper case

%#z

convert to lower case (consistently, unlike glibc)

<width>

Width digits can also be used after any modifiers and before the specifier (here marked as z), for example:

%4z

pad to 4 characters (with default padding character)

%_12z

pad with spaces to 12 characters

<alternate>

An optional E character indicates an alternate formatting. Currently this only affects %Z and %z.

%Ez

alternate formatting

<specifier>

For all types (note these three are done by formatTime, not by formatCharacter):

%%

%

%t

tab

%n

newline

TimeZone

For TimeZone (and ZonedTime and UTCTime):

%z

timezone offset in the format ±HHMM

%Ez

timezone offset in the format ±HH:MM

%Z

timezone name (or else offset in the format ±HHMM)

%EZ

timezone name (or else offset in the format ±HH:MM)

LocalTime

For LocalTime (and ZonedTime and UTCTime and UniversalTime):

%c

as dateTimeFmt locale (e.g. %a %b %e %H:%M:%S %Z %Y)

TimeOfDay

For TimeOfDay (and LocalTime and ZonedTime and UTCTime and UniversalTime):

%R

same as %H:%M

%T

same as %H:%M:%S

%X

as timeFmt locale (e.g. %H:%M:%S)

%r

as time12Fmt locale (e.g. %I:%M:%S %p)

%P

day-half of day from (amPm locale), converted to lowercase, am, pm

%p

day-half of day from (amPm locale), AM, PM

%H

hour of day (24-hour), 0-padded to two chars, 00 - 23

%k

hour of day (24-hour), space-padded to two chars, 0 - 23

%I

hour of day-half (12-hour), 0-padded to two chars, 01 - 12

%l

hour of day-half (12-hour), space-padded to two chars, 1 - 12

%M

minute of hour, 0-padded to two chars, 00 - 59

%S

second of minute (without decimal part), 0-padded to two chars, 00 - 60

%q

picosecond of second, 0-padded to twelve chars, 000000000000 - 999999999999.

%Q

decimal point and fraction of second, up to 12 second decimals, without trailing zeros. For a whole number of seconds, %Q omits the decimal point unless padding is specified.

UTCTime and ZonedTime

For UTCTime and ZonedTime:

%s

number of whole seconds since the Unix epoch. For times before the Unix epoch, this is a negative number. Note that in %s.%q and %s%Q the decimals are positive, not negative. For example, 0.9 seconds before the Unix epoch is formatted as -1.1 with %s%Q.

DayOfWeek

For DayOfWeek (and Day and LocalTime and ZonedTime and UTCTime and UniversalTime):

%u

day of week number for Week Date format, 1 (= Monday) - 7 (= Sunday)

%w

day of week number, 0 (= Sunday) - 6 (= Saturday)

%a

day of week, short form (snd from wDays locale), Sun - Sat

%A

day of week, long form (fst from wDays locale), Sunday - Saturday

Day

For Day (and LocalTime and ZonedTime and UTCTime and UniversalTime):

%D

same as %m/%d/%y

%F

same as %Y-%m-%d

%x

as dateFmt locale (e.g. %m/%d/%y)

%Y

year, no padding. Note %0Y and %_Y pad to four chars

%y

year of century, 0-padded to two chars, 00 - 99

%C

century, no padding. Note %0C and %_C pad to two chars

%B

month name, long form (fst from months locale), January - December

%b, %h

month name, short form (snd from months locale), Jan - Dec

%m

month of year, 0-padded to two chars, 01 - 12

%d

day of month, 0-padded to two chars, 01 - 31

%e

day of month, space-padded to two chars, 1 - 31

%j

day of year, 0-padded to three chars, 001 - 366

%f

century for Week Date format, no padding. Note %0f and %_f pad to two chars

%V

week of year for Week Date format, 0-padded to two chars, 01 - 53

%U

week of year where weeks start on Sunday (as sundayStartWeek), 0-padded to two chars, 00 - 53

%W

week of year where weeks start on Monday (as mondayStartWeek), 0-padded to two chars, 00 - 53

Duration types

The specifiers for DiffTime, NominalDiffTime, CalendarDiffDays, and CalendarDiffTime are semantically separate from the other types. Specifiers on negative time differences will generally be negative (think rem rather than mod).

NominalDiffTime and DiffTime

Note that a "minute" of DiffTime is simply 60 SI seconds, rather than a minute of civil time. Use NominalDiffTime to work with civil time, ignoring any leap seconds.

For NominalDiffTime and DiffTime:

%w

total whole weeks

%d

total whole days

%D

whole days of week

%h

total whole hours

%H

whole hours of day

%m

total whole minutes

%M

whole minutes of hour

%s

total whole seconds

%Es

total seconds, with decimal point and up to <width> (default 12) decimal places, without trailing zeros. For a whole number of seconds, %Es omits the decimal point unless padding is specified.

%0Es

total seconds, with decimal point and <width> (default 12) decimal places.

%S

whole seconds of minute

%ES

seconds of minute, with decimal point and up to <width> (default 12) decimal places, without trailing zeros. For a whole number of seconds, %ES omits the decimal point unless padding is specified.

%0ES

seconds of minute as two digits, with decimal point and <width> (default 12) decimal places.

CalendarDiffDays

For CalendarDiffDays (and CalendarDiffTime):

%y

total years

%b

total months

%B

months of year

%w

total weeks, not including months

%d

total days, not including months

%D

days of week

CalendarDiffTime

For CalendarDiffTime:

%h

total hours, not including months

%H

hours of day

%m

total minutes, not including months

%M

minutes of hour

%s

total whole seconds, not including months

%Es

total seconds, not including months, with decimal point and up to <width> (default 12) decimal places, without trailing zeros. For a whole number of seconds, %Es omits the decimal point unless padding is specified.

%0Es

total seconds, not including months, with decimal point and <width> (default 12) decimal places.

%S

whole seconds of minute

%ES

seconds of minute, with decimal point and up to <width> (default 12) decimal places, without trailing zeros. For a whole number of seconds, %ES omits the decimal point unless padding is specified.

%0ES

seconds of minute as two digits, with decimal point and <width> (default 12) decimal places.

UNIX-style parsing

parseTimeM Source

Parses a time value given a format string. Supports the same %-codes as formatTime, including %-, %_ and %0 modifiers, however padding widths are not supported. Case is not significant in the input string. Some variations in the input are accepted:

%z

accepts any of ±HHMM or ±HH:MM.

%Z

accepts any string of letters, or any of the formats accepted by %z.

%0Y

accepts exactly four digits.

%0G

accepts exactly four digits.

%0C

accepts exactly two digits.

%0f

accepts exactly two digits.

For example, to parse a date in YYYY-MM-DD format, while allowing the month and date to have optional leading zeros (notice the - modifier used for %m and %d):

Prelude Data.Time> parseTimeM True defaultTimeLocale "%Y-%-m-%-d" "2010-3-04" :: Maybe Day
Just 2010-03-04

parseTimeOrError Source

Parse a time value given a format string. Fails if the input could not be parsed using the given format. See parseTimeM for details.

readSTime Source

Parse a time value given a format string. See parseTimeM for details.

readPTime Source

Parse a time value given a format string. See parseTimeM for details.

parseTime Source

readTime Source

readsTime Source

class ParseTime t Source

The class of types which can be parsed given a UNIX-style time format string.

Locale

data TimeLocale Source

defaultTimeLocale :: TimeLocale Source

Locale representing American usage.

knownTimeZones contains only the ten time-zones mentioned in RFC 822 sec. 5: "UT", "GMT", "EST", "EDT", "CST", "CDT", "MST", "MDT", "PST", "PDT". Note that the parsing functions will regardless parse "UTC", single-letter military time-zones, and +HHMM format.

iso8601DateFormat :: Maybe String -> String Source

Construct format string according to ISO-8601.

The Maybe String argument allows to supply an optional time specification. E.g.:

iso8601DateFormat Nothing            == "%Y-%m-%d"           -- i.e. YYYY-MM-DD
iso8601DateFormat (Just "%H:%M:%S")  == "%Y-%m-%dT%H:%M:%S"  -- i.e. YYYY-MM-DDTHH:MM:SS

rfc822DateFormat :: String Source

Format string according to RFC822.