package core

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package core
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module Zone : sig ... end
module Ofday : sig ... end

A fully qualified point in time, independent of timezone.

include module type of Core_kernel.Time with type t := t and module Zone := Zone and module Ofday := Ofday
include module type of struct include Core_kernel.Core_kernel_private.Time_float0 end with type t := t with module Ofday := Ofday
val typerep_of_t : t Typerep_lib.Std.Typerep.t
val typename_of_t : t Typerep_lib.Std.Typename.t
include Core_kernel.Comparable.Polymorphic_compare with type t := t
include Base.Comparisons.Infix with type t := t
include Core_kernel.Interfaces.Robustly_comparable with type t := t
val next : t -> t

next t returns the next t (forwards in time)

val prev : t -> t

prev t returns the previous t (backwards in time)

val to_span_since_epoch : t -> Span.t
val of_span_since_epoch : Span.t -> t
include Core_kernel.Comparable.S_common with type t := t and module Replace_polymorphic_compare := Replace_polymorphic_compare
include Base.Comparable.S with type t := t
include Base.Comparisons.S with type t := t
include Base.Comparisons.Infix with type t := t
include Base.Comparator.S with type t := t

Represents a timezone-relative time, rather than an absolute time. This is equivalent to a Date.t and an Ofday.t with no time zone. A Relative_to_unspecified_zone.t does not correspond to a single, unambiguous point in time. Intended as a low-level back-end for high-level timezone-based functions; most clients should not use Relative_to_unspecified_zone.t.

val now : Base.Unit.t -> t

now () returns a t representing the current time

Basic operations on times
val add : t -> Span.t -> t

add t s adds the span s to time t and returns the resulting time.

NOTE: adding spans as a means of adding days is not accurate, and may run into trouble due to shifts in daylight savings time, float arithmetic issues, and leap seconds. See the comment at the top of Zone.mli for a more complete discussion of some of the issues of time-keeping. For spans that cross date boundaries, use date functions instead.

val sub : t -> Span.t -> t

sub t s subtracts the span s from time t and returns the resulting time. See important note for add.

val diff : t -> t -> Span.t

diff t1 t2 returns time t1 minus time t2.

val abs_diff : t -> t -> Span.t

abs_diff t1 t2 returns the absolute span of time t1 minus time t2.

Comparisons
val is_earlier : t -> than:t -> Base.Bool.t
val is_later : t -> than:t -> Base.Bool.t
Conversions
val of_date_ofday : zone:Zone.t -> Core_kernel__.Date0.t -> Ofday.t -> t
val of_date_ofday_precise : Core_kernel__.Date0.t -> Ofday.t -> zone:Zone.t -> [ `Once of t | `Twice of t * t | `Never of t ]

Because timezone offsets change throughout the year (clocks go forward or back) some local times can occur twice or not at all. In the case that they occur twice, this function gives `Twice with both occurrences in order; if they do not occur at all, this function gives `Never with the time at which the local clock skips over the desired time of day.

Note that this is really only intended to work with DST transitions and not unusual or dramatic changes, like the calendar change in 1752 (run "cal 9 1752" in a shell to see). In particular it makes the assumption that midnight of each day is unambiguous.

Most callers should use of_date_ofday rather than this function. In the `Twice and `Never cases, of_date_ofday will return reasonable times for most uses.

val to_date_ofday : t -> zone:Zone.t -> Core_kernel__.Date0.t * Ofday.t
val to_date_ofday_precise : t -> zone:Zone.t -> Core_kernel__.Date0.t * Ofday.t * [ `Only | `Also_at of t | `Also_skipped of Core_kernel__.Date0.t * Ofday.t ]

Always returns the Date.t * Ofday.t that to_date_ofday would have returned, and in addition returns a variant indicating whether the time is associated with a time zone transition.

      - `Only         -> there is a one-to-one mapping between [t]'s and
                         [Date.t * Ofday.t] pairs
      - `Also_at      -> there is another [t] that maps to the same [Date.t * Ofday.t]
                         (this date/time pair happened twice because the clock fell back)
      - `Also_skipped -> there is another [Date.t * Ofday.t] pair that never happened (due
                         to a jump forward) that [of_date_ofday] would map to the same
                         [t].
val to_date : t -> zone:Zone.t -> Core_kernel__.Date0.t
val to_ofday : t -> zone:Zone.t -> Ofday.t
val reset_date_cache : Base.Unit.t -> Base.Unit.t

For performance testing only; reset_date_cache () resets an internal cache used to speed up to_date and related functions when called repeatedly on times that fall within the same day.

Unlike Time_ns, this module purposely omits max_value and min_value: 1. They produce unintuitive corner cases because most people's mental models of time do not include +/- infinity as concrete values 2. In practice, when people ask for these values, it is for questionable uses, e.g., as null values to use in place of explicit options.

val epoch : t

midnight, Jan 1, 1970 in UTC

val convert : from_tz:Zone.t -> to_tz:Zone.t -> Core_kernel__.Date0.t -> Ofday.t -> Core_kernel__.Date0.t * Ofday.t

It's unspecified what happens if the given date/ofday/zone correspond to more than one date/ofday pair in the other zone.

val utc_offset : t -> zone:Zone.t -> Span.t
Other string conversions

The {to,of}_string functions in Time convert to UTC time, because a local time zone is not necessarily available. They are generous in what they will read in.

include Core_kernel.Interfaces.Stringable with type t := t
val to_filename_string : t -> zone:Zone.t -> Base.String.t

to_filename_string t ~zone converts t to string with format YYYY-MM-DD_HH-MM-SS.mmm which is suitable for using in filenames.

val of_filename_string : Base.String.t -> zone:Zone.t -> t

of_filename_string s ~zone converts s that has format YYYY-MM-DD_HH-MM-SS.mmm into time.

val to_string_trimmed : t -> zone:Zone.t -> Base.String.t

Same as to_string_abs, but removes trailing seconds and milliseconds if they are 0

val to_sec_string : t -> zone:Zone.t -> Base.String.t

Same as to_string_abs, but without milliseconds

val of_localized_string : zone:Zone.t -> Base.String.t -> t

of_localized_string ~zone str read in the given string assuming that it represents a time in zone and return the appropriate Time.t

val to_string_abs : t -> zone:Zone.t -> Base.String.t

to_string_abs ~zone t returns a string that represents an absolute time, rather than a local time with an assumed time zone. This string can be round-tripped, even on a machine in a different time zone than the machine that wrote the string.

The string will display the date and of-day of zone together with zone as an offset from UTC.

to_string_abs_trimmed is the same as to_string_abs, but drops trailing seconds and milliseconds if they are 0.

Note that the difference between to_string and to_string_abs is not that one returns an absolute time and one doesn't, but that to_string_abs lets you specify the time zone, while to_string takes it to be the local time zone.

val to_string_abs_trimmed : t -> zone:Zone.t -> Base.String.t
val to_string_abs_parts : t -> zone:Zone.t -> Base.String.t Base.List.t
val to_string_iso8601_basic : t -> zone:Zone.t -> Base.String.t

to_string_iso8601_basic return a string representation of the following form: %Y-%m-%dT%H:%M:%S.%s%Z e.g. to_string_iso8601_basic ~zone:Time.Zone.utc epoch = "1970-01-01T00:00:00.000000Z"

val occurrence : [ `First_after_or_at | `Last_before_or_at ] -> t -> ofday:Ofday.t -> zone:Zone.t -> t

occurrence side time ~ofday ~zone returns a Time.t that is the occurrence of ofday (in the given zone) that is the latest occurrence (<=) time or the earliest occurrence (>=) time, according to side.

NOTE: If the given time converted to wall clock time in the given zone is equal to ofday then the t returned will be equal to the t given.

val next_multiple : ?can_equal_after:Base.Bool.t -> base:t -> after:t -> interval:Span.t -> Base.Unit.t -> t

next_multiple ~base ~after ~interval returns the smallest time of the form:

time = base + k * interval

where k >= 0 and time > after. It is an error if interval <= 0.

Supplying ~can_equal_after:true allows the result to satisfy time >= after.

Sexp conversions use the local timezone by default. This can be overridden by calling set_sexp_zone.

The {to,of}_string functions in Time will produce times with time zone indications, but are generous in what they will read in. String/Sexp.t representations without time zone indications are assumed to be in the machine's local zone.

include Core_kernel.Identifiable.S with type t := t and type comparator_witness := comparator_witness and module Replace_polymorphic_compare := Replace_polymorphic_compare
val bin_read_t : t Bin_prot.Read.reader
val __bin_read_t__ : (Base.Int.t -> t) Bin_prot.Read.reader
val bin_reader_t : t Bin_prot.Type_class.reader
val bin_size_t : t Bin_prot.Size.sizer
val bin_write_t : t Bin_prot.Write.writer
val bin_writer_t : t Bin_prot.Type_class.writer
val bin_shape_t : Bin_prot.Shape.t
val t_of_sexp : Ppx_sexp_conv_lib.Sexp.t -> t
include Core_kernel.Identifiable.S_common with type t := t
val sexp_of_t : t -> Ppx_sexp_conv_lib.Sexp.t
include Base.Stringable.S with type t := t
val of_string : string -> t
val to_string : t -> string
include Base.Pretty_printer.S with type t := t
val pp : Base.Formatter.t -> t -> unit
include Core_kernel.Comparable.S_binable with type t := t with type comparator_witness := comparator_witness with module Replace_polymorphic_compare := Replace_polymorphic_compare
include Base.Comparable.S with type t := t with type comparator_witness := comparator_witness
include Base.Comparisons.S with type t := t
include Base.Comparisons.Infix with type t := t
val (>=) : t -> t -> bool
val (<=) : t -> t -> bool
val (=) : t -> t -> bool
val (>) : t -> t -> bool
val (<) : t -> t -> bool
val (<>) : t -> t -> bool
val equal : t -> t -> bool
val compare : t -> t -> int

compare t1 t2 returns 0 if t1 is equal to t2, a negative integer if t1 is less than t2, and a positive integer if t1 is greater than t2.

val min : t -> t -> t
val max : t -> t -> t
val ascending : t -> t -> int

ascending is identical to compare. descending x y = ascending y x. These are intended to be mnemonic when used like List.sort ~compare:ascending and List.sort ~cmp:descending, since they cause the list to be sorted in ascending or descending order, respectively.

val descending : t -> t -> int
val between : t -> low:t -> high:t -> bool

between t ~low ~high means low <= t <= high

val clamp_exn : t -> min:t -> max:t -> t

clamp_exn t ~min ~max returns t', the closest value to t such that between t' ~low:min ~high:max is true.

Raises if not (min <= max).

val clamp : t -> min:t -> max:t -> t Base.Or_error.t
include Base.Comparator.S with type t := t with type comparator_witness := comparator_witness
val validate_lbound : min:t Base.Maybe_bound.t -> t Base.Validate.check
val validate_ubound : max:t Base.Maybe_bound.t -> t Base.Validate.check
val validate_bound : min:t Base.Maybe_bound.t -> max:t Base.Maybe_bound.t -> t Base.Validate.check
include Core_kernel.Comparator.S with type t := t with type comparator_witness := comparator_witness
module Map : sig ... end
module Set : sig ... end
include Core_kernel.Hashable.S_binable with type t := t
val hash_fold_t : Base.Hash.state -> t -> Base.Hash.state
val hash : t -> Base.Hash.hash_value
val hashable : t Base.Hashable.t
module Table : sig ... end
module Hash_set : sig ... end
module Hash_queue : sig ... end
val get_sexp_zone : unit -> Zone.t
val set_sexp_zone : Zone.t -> unit
include Core_kernel.Robustly_comparable with type t := t
val (>=.) : t -> t -> bool
val (<=.) : t -> t -> bool
val (=.) : t -> t -> bool
val (>.) : t -> t -> bool
val (<.) : t -> t -> bool
val (<>.) : t -> t -> bool
val robustly_compare : t -> t -> int
val of_tm : Unix.tm -> zone:Zone.t -> t

of_tm converts a Unix.tm (mirroring a struct tm from the C stdlib) into a Time.t. Note that the tm_wday, tm_yday, and tm_isdst fields are ignored.

val to_string_fix_proto : [ `Utc | `Local ] -> t -> string
val of_string_fix_proto : [ `Utc | `Local ] -> string -> t
val of_string_abs : string -> t

of_string_abs s is like of_string, but demands that s indicate the timezone the time is expressed in.

val of_string_gen : if_no_timezone:[ `Fail | `Local | `Use_this_one of Zone.t ] -> string -> t

of_string_gen ~if_no_timezone s attempts to parse s to a t. If s doesn't supply a time zone if_no_timezone is consulted.

val t_of_sexp_abs : Core_kernel.Sexp.t -> t

t_of_sexp_abs sexp as t_of_sexp, but demands that sexp indicate the timezone the time is expressed in.

val sexp_of_t_abs : t -> zone:Zone.t -> Core_kernel.Sexp.t
Miscellaneous
val pause : Span.t -> unit

pause span sleeps for span time.

val interruptible_pause : Span.t -> [ `Ok | `Remaining of Span.t ]

interruptible_pause span sleeps for span time unless interrupted (e.g. by delivery of a signal), in which case the remaining unslept portion of time is returned.

val pause_forever : unit -> Core_kernel.Nothing.t

pause_forever sleeps indefinitely.

val format : t -> string -> zone:Zone.t -> string

format t fmt formats the given time according to fmt, which follows the formatting rules given in 'man strftime'. The time is output in the given timezone.

      %Y - year (4 digits)
      %y - year (2 digits)
      %m - month
      %d - day
      %H - hour
      %M - minute
      %S - second

a common choice would be: %Y-%m-%d %H:%M:%S

val parse : string -> fmt:string -> zone:Zone.t -> t

parse string ~fmt ~zone parses string, according to fmt, which follows the formatting rules given in 'man strptime'. The time is assumed to be in the given timezone.

      %Y - year (4 digits)
      %y - year (2 digits)
      %m - month
      %d - day
      %H - hour
      %M - minute
      %S - second
module Exposed_for_tests : sig ... end
module Stable : sig ... end