chrono/src/lib.rs

708 lines
27 KiB
Rust

// This is a part of rust-chrono.
// Copyright (c) 2014-2015, Kang Seonghoon.
// See README.md and LICENSE.txt for details.
//! # Chrono 0.2.22
//!
//! Date and time handling for Rust. (also known as `rust-chrono`)
//! It aims to be a feature-complete superset of
//! the [time](https://github.com/rust-lang-deprecated/time) library.
//! In particular,
//!
//! * Chrono strictly adheres to ISO 8601.
//! * Chrono is timezone-aware by default, with separate timezone-naive types.
//! * Chrono is space-optimal and (while not being the primary goal) reasonably efficient.
//!
//! There were several previous attempts to bring a good date and time library to Rust,
//! which Chrono builts upon and should acknowledge:
//!
//! * [Initial research on
//! the wiki](https://github.com/rust-lang/rust-wiki-backup/blob/master/Lib-datetime.md)
//! * Dietrich Epp's [datetime-rs](https://github.com/depp/datetime-rs)
//! * Luis de Bethencourt's [rust-datetime](https://github.com/luisbg/rust-datetime)
//!
//! ## Usage
//!
//! Put this in your `Cargo.toml`:
//!
//! ```toml
//! [dependencies]
//! chrono = "0.2"
//! ```
//!
//! Or, if you want [Serde](https://github.com/serde-rs/serde) or
//! [rustc-serialize](https://github.com/rust-lang-nursery/rustc-serialize) support,
//! include the features like this:
//!
//! ```toml
//! [dependencies]
//! chrono = { version = "0.2", features = ["serde", "rustc-serialize"] }
//! ```
//!
//! Then put this in your crate root:
//!
//! ```rust
//! extern crate chrono;
//! ```
//!
//! ## Overview
//!
//! ### Duration
//!
//! [**`Duration`**](./struct.Duration.html)
//! represents the magnitude of a time span. `Duration` used to be provided by Chrono.
//! It has been moved to the `time` crate as the
//! [`time::Duration`](https://doc.rust-lang.org/time/time/struct.Duration.html) type, but is
//! still re-exported from Chrono.
//!
//! ### Date and Time
//!
//! Chrono provides a
//! [**`DateTime`**](./datetime/struct.DateTime.html)
//! type to represent a date and a time in a timezone.
//!
//! For more abstract moment-in-time tracking such as internal timekeeping
//! that is unconcerned with timezones, consider
//! [`time::SystemTime`](https://doc.rust-lang.org/std/time/struct.SystemTime.html),
//! which tracks your system clock, or
//! [`time::Instant`](https://doc.rust-lang.org/std/time/struct.Instant.html), which
//! is an opaque but monotonically-increasing representation of a moment in time.
//!
//! `DateTime` is timezone-aware and must be constructed from
//! the [**`TimeZone`**](./offset/trait.TimeZone.html) object,
//! which defines how the local date is converted to and back from the UTC date.
//! There are three well-known `TimeZone` implementations:
//!
//! * [**`UTC`**](./offset/utc/struct.UTC.html) specifies the UTC time zone. It is most efficient.
//!
//! * [**`Local`**](./offset/local/struct.Local.html) specifies the system local time zone.
//!
//! * [**`FixedOffset`**](./offset/fixed/struct.FixedOffset.html) specifies
//! an arbitrary, fixed time zone such as UTC+09:00 or UTC-10:30.
//! This often results from the parsed textual date and time.
//! Since it stores the most information and does not depend on the system environment,
//! you would want to normalize other `TimeZone`s into this type.
//!
//! `DateTime`s with different `TimeZone` types are distinct and do not mix,
//! but can be converted to each other using
//! the [`DateTime::with_timezone`](./datetime/struct.DateTime.html#method.with_timezone) method.
//!
//! You can get the current date and time in the UTC time zone
//! ([`UTC::now()`](./offset/utc/struct.UTC.html#method.now))
//! or in the local time zone
//! ([`Local::now()`](./offset/local/struct.Local.html#method.now)).
//!
//! ~~~~ {.rust}
//! use chrono::*;
//!
//! let utc: DateTime<UTC> = UTC::now(); // e.g. `2014-11-28T12:45:59.324310806Z`
//! let local: DateTime<Local> = Local::now(); // e.g. `2014-11-28T21:45:59.324310806+09:00`
//! # let _ = utc; let _ = local;
//! ~~~~
//!
//! Alternatively, you can create your own date and time.
//! This is a bit verbose due to Rust's lack of function and method overloading,
//! but in turn we get a rich combination of initialization methods.
//!
//! ~~~~ {.rust}
//! use chrono::*;
//!
//! let dt = UTC.ymd(2014, 7, 8).and_hms(9, 10, 11); // `2014-07-08T09:10:11Z`
//! // July 8 is 188th day of the year 2014 (`o` for "ordinal")
//! assert_eq!(dt, UTC.yo(2014, 189).and_hms(9, 10, 11));
//! // July 8 is Tuesday in ISO week 28 of the year 2014.
//! assert_eq!(dt, UTC.isoywd(2014, 28, Weekday::Tue).and_hms(9, 10, 11));
//!
//! let dt = UTC.ymd(2014, 7, 8).and_hms_milli(9, 10, 11, 12); // `2014-07-08T09:10:11.012Z`
//! assert_eq!(dt, UTC.ymd(2014, 7, 8).and_hms_micro(9, 10, 11, 12_000));
//! assert_eq!(dt, UTC.ymd(2014, 7, 8).and_hms_nano(9, 10, 11, 12_000_000));
//!
//! // dynamic verification
//! assert_eq!(UTC.ymd_opt(2014, 7, 8).and_hms_opt(21, 15, 33),
//! LocalResult::Single(UTC.ymd(2014, 7, 8).and_hms(21, 15, 33)));
//! assert_eq!(UTC.ymd_opt(2014, 7, 8).and_hms_opt(80, 15, 33), LocalResult::None);
//! assert_eq!(UTC.ymd_opt(2014, 7, 38).and_hms_opt(21, 15, 33), LocalResult::None);
//!
//! // other time zone objects can be used to construct a local datetime.
//! // obviously, `local_dt` is normally different from `dt`, but `fixed_dt` should be identical.
//! let local_dt = Local.ymd(2014, 7, 8).and_hms_milli(9, 10, 11, 12);
//! let fixed_dt = FixedOffset::east(9 * 3600).ymd(2014, 7, 8).and_hms_milli(18, 10, 11, 12);
//! assert_eq!(dt, fixed_dt);
//! # let _ = local_dt;
//! ~~~~
//!
//! Various properties are available to the date and time, and can be altered individually.
//! Most of them are defined in the traits [`Datelike`](./trait.Datelike.html) and
//! [`Timelike`](./trait.Timelike.html) which you should `use` before.
//! Addition and subtraction is also supported.
//! The following illustrates most supported operations to the date and time:
//!
//! ~~~~ {.rust}
//! use chrono::*;
//!
//! # /* we intentionally fake the datetime...
//! // assume this returned `2014-11-28T21:45:59.324310806+09:00`:
//! let dt = Local::now();
//! # */ // up to here. we now define a fixed datetime for the illustrative purpose.
//! # let dt = FixedOffset::east(9*3600).ymd(2014, 11, 28).and_hms_nano(21, 45, 59, 324310806);
//!
//! // property accessors
//! assert_eq!((dt.year(), dt.month(), dt.day()), (2014, 11, 28));
//! assert_eq!((dt.month0(), dt.day0()), (10, 27)); // for unfortunate souls
//! assert_eq!((dt.hour(), dt.minute(), dt.second()), (21, 45, 59));
//! assert_eq!(dt.weekday(), Weekday::Fri);
//! assert_eq!(dt.weekday().number_from_monday(), 5); // Mon=1, ..., Sat=7
//! assert_eq!(dt.ordinal(), 332); // the day of year
//! assert_eq!(dt.num_days_from_ce(), 735565); // the number of days from and including Jan 1, 1
//!
//! // time zone accessor and manipulation
//! assert_eq!(dt.offset().local_minus_utc(), Duration::hours(9));
//! assert_eq!(dt.timezone(), FixedOffset::east(9 * 3600));
//! assert_eq!(dt.with_timezone(&UTC), UTC.ymd(2014, 11, 28).and_hms_nano(12, 45, 59, 324310806));
//!
//! // a sample of property manipulations (validates dynamically)
//! assert_eq!(dt.with_day(29).unwrap().weekday(), Weekday::Sat); // 2014-11-29 is Saturday
//! assert_eq!(dt.with_day(32), None);
//! assert_eq!(dt.with_year(-300).unwrap().num_days_from_ce(), -109606); // November 29, 301 BCE
//!
//! // arithmetic operations
//! assert_eq!(UTC.ymd(2014, 11, 14).and_hms(8, 9, 10) - UTC.ymd(2014, 11, 14).and_hms(10, 9, 8),
//! Duration::seconds(-2 * 3600 + 2));
//! assert_eq!(UTC.ymd(1970, 1, 1).and_hms(0, 0, 0) + Duration::seconds(1_000_000_000),
//! UTC.ymd(2001, 9, 9).and_hms(1, 46, 40));
//! assert_eq!(UTC.ymd(1970, 1, 1).and_hms(0, 0, 0) - Duration::seconds(1_000_000_000),
//! UTC.ymd(1938, 4, 24).and_hms(22, 13, 20));
//! ~~~~
//!
//! Formatting is done via the [`format`](./datetime/struct.DateTime.html#method.format) method,
//! which format is equivalent to the familiar `strftime` format.
//! (See the [`format::strftime` module documentation](./format/strftime/index.html#specifiers)
//! for full syntax.)
//!
//! The default `to_string` method and `{:?}` specifier also give a reasonable representation.
//! Chrono also provides [`to_rfc2822`](./datetime/struct.DateTime.html#method.to_rfc2822) and
//! [`to_rfc3339`](./datetime/struct.DateTime.html#method.to_rfc3339) methods
//! for well-known formats.
//!
//! ~~~~ {.rust}
//! use chrono::*;
//!
//! let dt = UTC.ymd(2014, 11, 28).and_hms(12, 0, 9);
//! assert_eq!(dt.format("%Y-%m-%d %H:%M:%S").to_string(), "2014-11-28 12:00:09");
//! assert_eq!(dt.format("%a %b %e %T %Y").to_string(), "Fri Nov 28 12:00:09 2014");
//! assert_eq!(dt.format("%a %b %e %T %Y").to_string(), dt.format("%c").to_string());
//!
//! assert_eq!(dt.to_string(), "2014-11-28 12:00:09 UTC");
//! assert_eq!(dt.to_rfc2822(), "Fri, 28 Nov 2014 12:00:09 +0000");
//! assert_eq!(dt.to_rfc3339(), "2014-11-28T12:00:09+00:00");
//! assert_eq!(format!("{:?}", dt), "2014-11-28T12:00:09Z");
//! ~~~~
//!
//! Parsing can be done with three methods:
//!
//! 1. The standard [`FromStr`](https://doc.rust-lang.org/std/str/trait.FromStr.html) trait
//! (and [`parse`](https://doc.rust-lang.org/std/primitive.str.html#method.parse) method
//! on a string) can be used for parsing `DateTime<FixedOffset>`, `DateTime<UTC>` and
//! `DateTime<Local>` values. This parses what the `{:?}`
//! ([`std::fmt::Debug`](https://doc.rust-lang.org/std/fmt/trait.Debug.html))
//! format specifier prints, and requires the offset to be present.
//!
//! 2. [`DateTime::parse_from_str`](./datetime/struct.DateTime.html#method.parse_from_str) parses
//! a date and time with offsets and returns `DateTime<FixedOffset>`.
//! This should be used when the offset is a part of input and the caller cannot guess that.
//! It *cannot* be used when the offset can be missing.
//! [`DateTime::parse_from_rfc2822`](./datetime/struct.DateTime.html#method.parse_from_rfc2822)
//! and
//! [`DateTime::parse_from_rfc3339`](./datetime/struct.DateTime.html#method.parse_from_rfc3339)
//! are similar but for well-known formats.
//!
//! 3. [`Offset::datetime_from_str`](./offset/trait.TimeZone.html#method.datetime_from_str) is
//! similar but returns `DateTime` of given offset.
//! When the explicit offset is missing from the input, it simply uses given offset.
//! It issues an error when the input contains an explicit offset different
//! from the current offset.
//!
//! More detailed control over the parsing process is available via
//! [`format`](./format/index.html) module.
//!
//! ~~~~ {.rust}
//! use chrono::*;
//!
//! let dt = UTC.ymd(2014, 11, 28).and_hms(12, 0, 9);
//! let fixed_dt = dt.with_timezone(&FixedOffset::east(9*3600));
//!
//! // method 1
//! assert_eq!("2014-11-28T12:00:09Z".parse::<DateTime<UTC>>(), Ok(dt.clone()));
//! assert_eq!("2014-11-28T21:00:09+09:00".parse::<DateTime<UTC>>(), Ok(dt.clone()));
//! assert_eq!("2014-11-28T21:00:09+09:00".parse::<DateTime<FixedOffset>>(), Ok(fixed_dt.clone()));
//!
//! // method 2
//! assert_eq!(DateTime::parse_from_str("2014-11-28 21:00:09 +09:00", "%Y-%m-%d %H:%M:%S %z"),
//! Ok(fixed_dt.clone()));
//! assert_eq!(DateTime::parse_from_rfc2822("Fri, 28 Nov 2014 21:00:09 +0900"),
//! Ok(fixed_dt.clone()));
//! assert_eq!(DateTime::parse_from_rfc3339("2014-11-28T21:00:09+09:00"), Ok(fixed_dt.clone()));
//!
//! // method 3
//! assert_eq!(UTC.datetime_from_str("2014-11-28 12:00:09", "%Y-%m-%d %H:%M:%S"), Ok(dt.clone()));
//! assert_eq!(UTC.datetime_from_str("Fri Nov 28 12:00:09 2014", "%a %b %e %T %Y"), Ok(dt.clone()));
//!
//! // oops, the year is missing!
//! assert!(UTC.datetime_from_str("Fri Nov 28 12:00:09", "%a %b %e %T %Y").is_err());
//! // oops, the format string does not include the year at all!
//! assert!(UTC.datetime_from_str("Fri Nov 28 12:00:09", "%a %b %e %T").is_err());
//! // oops, the weekday is incorrect!
//! assert!(UTC.datetime_from_str("Sat Nov 28 12:00:09 2014", "%a %b %e %T %Y").is_err());
//! ~~~~
//!
//! ### Individual date
//!
//! Chrono also provides an individual date type ([**`Date`**](./date/struct.Date.html)).
//! It also has time zones attached, and have to be constructed via time zones.
//! Most operations available to `DateTime` are also available to `Date` whenever appropriate.
//!
//! ~~~~ {.rust}
//! use chrono::*;
//!
//! # // these *may* fail, but only very rarely. just rerun the test if you were that unfortunate ;)
//! assert_eq!(UTC::today(), UTC::now().date());
//! assert_eq!(Local::today(), Local::now().date());
//!
//! assert_eq!(UTC.ymd(2014, 11, 28).weekday(), Weekday::Fri);
//! assert_eq!(UTC.ymd_opt(2014, 11, 31), LocalResult::None);
//! assert_eq!(UTC.ymd(2014, 11, 28).and_hms_milli(7, 8, 9, 10).format("%H%M%S").to_string(),
//! "070809");
//! ~~~~
//!
//! There is no timezone-aware `Time` due to the lack of usefulness and also the complexity.
//!
//! `DateTime` has [`date`](./datetime/struct.DateTime.html#method.date) method
//! which returns a `Date` which represents its date component.
//! There is also a [`time`](./datetime/struct.DateTime.html#method.time) method,
//! which simply returns a naive local time described below.
//!
//! ### Naive date and time
//!
//! Chrono provides naive counterparts to `Date`, (non-existent) `Time` and `DateTime`
//! as [**`NaiveDate`**](./naive/date/struct.NaiveDate.html),
//! [**`NaiveTime`**](./naive/time/struct.NaiveTime.html) and
//! [**`NaiveDateTime`**](./naive/datetime/struct.NaiveDateTime.html) respectively.
//!
//! They have almost equivalent interfaces as their timezone-aware twins,
//! but are not associated to time zones obviously and can be quite low-level.
//! They are mostly useful for building blocks for higher-level types.
//!
//! Timezone-aware `DateTime` and `Date` types have two methods returning naive versions:
//! [`naive_local`](./datetime/struct.DateTime.html#method.naive_local) returns
//! a view to the naive local time,
//! and [`naive_utc`](./datetime/struct.DateTime.html#method.naive_utc) returns
//! a view to the naive UTC time.
//!
//! ## Limitations
//!
//! Only proleptic Gregorian calendar (i.e. extended to support older dates) is supported.
//! Be very careful if you really have to deal with pre-20C dates, they can be in Julian or others.
//!
//! Date types are limited in about +/- 262,000 years from the common epoch.
//! Time types are limited in the nanosecond accuracy.
//!
//! [Leap seconds are supported in the representation but
//! Chrono doesn't try to make use of them](./naive/time/index.html#leap-second-handling).
//! (The main reason is that leap seconds are not really predictable.)
//! Almost *every* operation over the possible leap seconds will ignore them.
//! Consider using `NaiveDateTime` with the implicit TAI (International Atomic Time) scale
//! if you want.
//!
//! Chrono inherently does not support an inaccurate or partial date and time representation.
//! Any operation that can be ambiguous will return `None` in such cases.
//! For example, "a month later" of 2014-01-30 is not well-defined
//! and consequently `UTC.ymd(2014, 1, 30).with_month(2)` returns `None`.
//!
//! Advanced time zone handling is not yet supported (but is planned in 0.3).
#![doc(html_root_url = "https://lifthrasiir.github.io/rust-chrono/")]
#![cfg_attr(bench, feature(test))] // lib stability features as per RFC #507
#![deny(missing_docs)]
extern crate time as stdtime;
extern crate num;
#[cfg(feature = "rustc-serialize")]
extern crate rustc_serialize;
#[cfg(feature = "serde")]
extern crate serde;
pub use duration::Duration;
pub use offset::{TimeZone, Offset, LocalResult};
pub use offset::utc::UTC;
pub use offset::fixed::FixedOffset;
pub use offset::local::Local;
pub use naive::date::NaiveDate;
pub use naive::time::NaiveTime;
pub use naive::datetime::NaiveDateTime;
pub use date::Date;
pub use datetime::DateTime;
pub use format::{ParseError, ParseResult};
// useful throughout the codebase
macro_rules! try_opt {
($e:expr) => (match $e { Some(v) => v, None => return None })
}
mod div;
pub mod duration {
//! ISO 8601 duration.
//!
//! This used to be a part of rust-chrono,
//! but has been subsequently merged into Rust's standard library.
pub use stdtime::Duration;
}
pub mod offset;
pub mod naive {
//! Date and time types which do not concern about the timezones.
//!
//! They are primarily building blocks for other types
//! (e.g. [`TimeZone`](../offset/trait.TimeZone.html)),
//! but can be also used for the simpler date and time handling.
pub mod date;
pub mod time;
pub mod datetime;
}
pub mod date;
pub mod datetime;
pub mod format;
/// The day of week (DOW).
///
/// The order of the days of week depends on the context.
/// One should prefer `*_from_monday` or `*_from_sunday` methods to get the correct result.
#[derive(PartialEq, Eq, Copy, Clone, Debug)]
#[cfg_attr(feature = "rustc-serialize", derive(RustcEncodable, RustcDecodable))]
pub enum Weekday {
/// Monday.
Mon = 0,
/// Tuesday.
Tue = 1,
/// Wednesday.
Wed = 2,
/// Thursday.
Thu = 3,
/// Friday.
Fri = 4,
/// Saturday.
Sat = 5,
/// Sunday.
Sun = 6,
}
impl Weekday {
/// The next day in the week.
#[inline]
pub fn succ(&self) -> Weekday {
match *self {
Weekday::Mon => Weekday::Tue,
Weekday::Tue => Weekday::Wed,
Weekday::Wed => Weekday::Thu,
Weekday::Thu => Weekday::Fri,
Weekday::Fri => Weekday::Sat,
Weekday::Sat => Weekday::Sun,
Weekday::Sun => Weekday::Mon,
}
}
/// The previous day in the week.
#[inline]
pub fn pred(&self) -> Weekday {
match *self {
Weekday::Mon => Weekday::Sun,
Weekday::Tue => Weekday::Mon,
Weekday::Wed => Weekday::Tue,
Weekday::Thu => Weekday::Wed,
Weekday::Fri => Weekday::Thu,
Weekday::Sat => Weekday::Fri,
Weekday::Sun => Weekday::Sat,
}
}
/// Returns a DOW number starting from Monday = 1. (ISO 8601 weekday number)
#[inline]
pub fn number_from_monday(&self) -> u32 {
match *self {
Weekday::Mon => 1,
Weekday::Tue => 2,
Weekday::Wed => 3,
Weekday::Thu => 4,
Weekday::Fri => 5,
Weekday::Sat => 6,
Weekday::Sun => 7,
}
}
/// Returns a DOW number starting from Sunday = 1.
#[inline]
pub fn number_from_sunday(&self) -> u32 {
match *self {
Weekday::Mon => 2,
Weekday::Tue => 3,
Weekday::Wed => 4,
Weekday::Thu => 5,
Weekday::Fri => 6,
Weekday::Sat => 7,
Weekday::Sun => 1,
}
}
/// Returns a DOW number starting from Monday = 0.
#[inline]
pub fn num_days_from_monday(&self) -> u32 {
match *self {
Weekday::Mon => 0,
Weekday::Tue => 1,
Weekday::Wed => 2,
Weekday::Thu => 3,
Weekday::Fri => 4,
Weekday::Sat => 5,
Weekday::Sun => 6,
}
}
/// Returns a DOW number starting from Sunday = 0.
#[inline]
pub fn num_days_from_sunday(&self) -> u32 {
match *self {
Weekday::Mon => 1,
Weekday::Tue => 2,
Weekday::Wed => 3,
Weekday::Thu => 4,
Weekday::Fri => 5,
Weekday::Sat => 6,
Weekday::Sun => 0,
}
}
}
/// Any weekday can be represented as an integer from 0 to 6,
/// which equals to `Weekday::num_days_from_monday` in this implementation.
/// Do not heavily depend on this though; use explicit methods whenever possible.
impl num::traits::FromPrimitive for Weekday {
#[inline]
fn from_i64(n: i64) -> Option<Weekday> {
match n {
0 => Some(Weekday::Mon),
1 => Some(Weekday::Tue),
2 => Some(Weekday::Wed),
3 => Some(Weekday::Thu),
4 => Some(Weekday::Fri),
5 => Some(Weekday::Sat),
6 => Some(Weekday::Sun),
_ => None,
}
}
#[inline]
fn from_u64(n: u64) -> Option<Weekday> {
match n {
0 => Some(Weekday::Mon),
1 => Some(Weekday::Tue),
2 => Some(Weekday::Wed),
3 => Some(Weekday::Thu),
4 => Some(Weekday::Fri),
5 => Some(Weekday::Sat),
6 => Some(Weekday::Sun),
_ => None,
}
}
}
/// The common set of methods for date component.
pub trait Datelike: Sized {
/// Returns the year number in the [calendar date](./naive/date/index.html#calendar-date).
fn year(&self) -> i32;
/// Returns the absolute year number starting from 1 with a boolean flag,
/// which is false when the year predates the epoch (BCE/BC) and true otherwise (CE/AD).
#[inline]
fn year_ce(&self) -> (bool, u32) {
let year = self.year();
if year < 1 {
(false, (1 - year) as u32)
} else {
(true, year as u32)
}
}
/// Returns the month number starting from 1.
///
/// The return value ranges from 1 to 12.
fn month(&self) -> u32;
/// Returns the month number starting from 0.
///
/// The return value ranges from 0 to 11.
fn month0(&self) -> u32;
/// Returns the day of month starting from 1.
///
/// The return value ranges from 1 to 31. (The last day of month differs by months.)
fn day(&self) -> u32;
/// Returns the day of month starting from 0.
///
/// The return value ranges from 0 to 30. (The last day of month differs by months.)
fn day0(&self) -> u32;
/// Returns the day of year starting from 1.
///
/// The return value ranges from 1 to 366. (The last day of year differs by years.)
fn ordinal(&self) -> u32;
/// Returns the day of year starting from 0.
///
/// The return value ranges from 0 to 365. (The last day of year differs by years.)
fn ordinal0(&self) -> u32;
/// Returns the day of week.
fn weekday(&self) -> Weekday;
/// Returns the ISO week date: an adjusted year, week number and day of week.
/// The adjusted year may differ from that of the calendar date.
fn isoweekdate(&self) -> (i32, u32, Weekday);
/// Makes a new value with the year number changed.
///
/// Returns `None` when the resulting value would be invalid.
fn with_year(&self, year: i32) -> Option<Self>;
/// Makes a new value with the month number (starting from 1) changed.
///
/// Returns `None` when the resulting value would be invalid.
fn with_month(&self, month: u32) -> Option<Self>;
/// Makes a new value with the month number (starting from 0) changed.
///
/// Returns `None` when the resulting value would be invalid.
fn with_month0(&self, month0: u32) -> Option<Self>;
/// Makes a new value with the day of month (starting from 1) changed.
///
/// Returns `None` when the resulting value would be invalid.
fn with_day(&self, day: u32) -> Option<Self>;
/// Makes a new value with the day of month (starting from 0) changed.
///
/// Returns `None` when the resulting value would be invalid.
fn with_day0(&self, day0: u32) -> Option<Self>;
/// Makes a new value with the day of year (starting from 1) changed.
///
/// Returns `None` when the resulting value would be invalid.
fn with_ordinal(&self, ordinal: u32) -> Option<Self>;
/// Makes a new value with the day of year (starting from 0) changed.
///
/// Returns `None` when the resulting value would be invalid.
fn with_ordinal0(&self, ordinal0: u32) -> Option<Self>;
/// Returns the number of days since January 1, 1 (Day 1) in the proleptic Gregorian calendar.
fn num_days_from_ce(&self) -> i32 {
// we know this wouldn't overflow since year is limited to 1/2^13 of i32's full range.
let mut year = self.year() - 1;
let mut ndays = 0;
if year < 0 {
let excess = 1 + (-year) / 400;
year += excess * 400;
ndays -= excess * 146097;
}
let div_100 = year / 100;
ndays += ((year * 1461) >> 2) - div_100 + (div_100 >> 2);
ndays + self.ordinal() as i32
}
}
/// The common set of methods for time component.
pub trait Timelike: Sized {
/// Returns the hour number from 0 to 23.
fn hour(&self) -> u32;
/// Returns the hour number from 1 to 12 with a boolean flag,
/// which is false for AM and true for PM.
#[inline]
fn hour12(&self) -> (bool, u32) {
let hour = self.hour();
let mut hour12 = hour % 12;
if hour12 == 0 {
hour12 = 12;
}
(hour >= 12, hour12)
}
/// Returns the minute number from 0 to 59.
fn minute(&self) -> u32;
/// Returns the second number from 0 to 59.
fn second(&self) -> u32;
/// Returns the number of nanoseconds since the whole non-leap second.
/// The range from 1,000,000,000 to 1,999,999,999 represents
/// the [leap second](./naive/time/index.html#leap-second-handling).
fn nanosecond(&self) -> u32;
/// Makes a new value with the hour number changed.
///
/// Returns `None` when the resulting value would be invalid.
fn with_hour(&self, hour: u32) -> Option<Self>;
/// Makes a new value with the minute number changed.
///
/// Returns `None` when the resulting value would be invalid.
fn with_minute(&self, min: u32) -> Option<Self>;
/// Makes a new value with the second number changed.
///
/// Returns `None` when the resulting value would be invalid.
/// As with the [`second`](#tymethod.second) method,
/// the input range is restricted to 0 through 59.
fn with_second(&self, sec: u32) -> Option<Self>;
/// Makes a new value with nanoseconds since the whole non-leap second changed.
///
/// Returns `None` when the resulting value would be invalid.
/// As with the [`nanosecond`](#tymethod.nanosecond) method,
/// the input range can exceed 1,000,000,000 for leap seconds.
fn with_nanosecond(&self, nano: u32) -> Option<Self>;
/// Returns the number of non-leap seconds past the last midnight.
#[inline]
fn num_seconds_from_midnight(&self) -> u32 {
self.hour() * 3600 + self.minute() * 60 + self.second()
}
}
#[test]
fn test_readme_doomsday() {
use num::iter::range_inclusive;
for y in range_inclusive(naive::date::MIN.year(), naive::date::MAX.year()) {
// even months
let d4 = NaiveDate::from_ymd(y, 4, 4);
let d6 = NaiveDate::from_ymd(y, 6, 6);
let d8 = NaiveDate::from_ymd(y, 8, 8);
let d10 = NaiveDate::from_ymd(y, 10, 10);
let d12 = NaiveDate::from_ymd(y, 12, 12);
// nine to five, seven-eleven
let d59 = NaiveDate::from_ymd(y, 5, 9);
let d95 = NaiveDate::from_ymd(y, 9, 5);
let d711 = NaiveDate::from_ymd(y, 7, 11);
let d117 = NaiveDate::from_ymd(y, 11, 7);
// "March 0"
let d30 = NaiveDate::from_ymd(y, 3, 1).pred();
let weekday = d30.weekday();
let other_dates = [d4, d6, d8, d10, d12, d59, d95, d711, d117];
assert!(other_dates.iter().all(|d| d.weekday() == weekday));
}
}