About

Date/time library

See also the API documentation and dtg crate.

Examples

use chrono::{TimeZone, Utc};
use dtg_lib::{tz, Dtg, Format};

let epoch = 1658448142;
let nanoseconds = 936196858;
let rfc_3339 = "2022-07-22T00:02:22Z";
let default_utc = "Fri 22 Jul 2022 00:02:22 UTC";
let default_mt = "Thu 21 Jul 2022 18:02:22 MDT";
let x = "Xg6L02M";
let a_utc = format!("{epoch}.000000000\n{rfc_3339}\n{default_utc}\n{default_utc}");
let a_mt = format!("{epoch}.000000000\n{rfc_3339}\n{default_utc}\n{default_mt}");
let day_of_week_utc = "Friday";
let day_of_week_mt = "Thursday";
let tz_utc = tz("UTC").ok();
let tz_mt = tz("MST7MDT").ok();
let default_fmt = Some(Format::default());
let day_of_week_fmt = Some(Format::custom("%A"));

// Create Dtg

let dtg_1_str = format!("{}", epoch);

let dtg_1_ts = Dtg::from(&dtg_1_str).unwrap();
let dtg_1_dt = Dtg::from_dt(&Utc.timestamp(epoch, 0));
let dtg_1_x = Dtg::from_x(x).unwrap();

assert_eq!(dtg_1_ts, dtg_1_dt);
assert_eq!(dtg_1_dt, dtg_1_x);
assert_eq!(dtg_1_x, dtg_1_ts);

// Create Dtg with nanoseconds

let dtg_2_str = format!("{}.{}", epoch, nanoseconds);

let dtg_2_ts = Dtg::from(&dtg_2_str).unwrap();
let dtg_2_dt = Dtg::from_dt(&Utc.timestamp(epoch, nanoseconds));

assert_eq!(dtg_2_ts, dtg_2_dt);

// Default format

assert_eq!(dtg_1_ts.default(&None), default_utc);
assert_eq!(dtg_1_ts.default(&tz_utc), default_utc);
assert_eq!(dtg_1_ts.default(&tz_mt), default_mt);

assert_eq!(dtg_1_ts.format(&default_fmt, &None), default_utc);
assert_eq!(dtg_1_ts.format(&default_fmt, &tz_utc), default_utc);
assert_eq!(dtg_1_ts.format(&default_fmt, &tz_mt), default_mt);

// RFC 3339 format

assert_eq!(dtg_1_ts.rfc_3339(), rfc_3339);
assert_eq!(dtg_1_ts.format(&None, &None), rfc_3339);

// "x" format

assert_eq!(dtg_1_ts.x_format(), x);
assert_eq!(dtg_1_ts.format(&Some(Format::X), &None), x);

// "a" format

assert_eq!(dtg_1_ts.a_format(&None), a_utc);
assert_eq!(dtg_1_ts.a_format(&tz_utc), a_utc);
assert_eq!(dtg_1_ts.a_format(&tz_mt), a_mt);

assert_eq!(dtg_1_ts.format(&Some(Format::A), &None), a_utc);
assert_eq!(dtg_1_ts.format(&Some(Format::A), &tz_utc), a_utc);
assert_eq!(dtg_1_ts.format(&Some(Format::A), &tz_mt), a_mt);

// Custom format

assert_eq!(dtg_1_ts.format(&day_of_week_fmt, &None), day_of_week_utc);
assert_eq!(dtg_1_ts.format(&day_of_week_fmt, &tz_mt), day_of_week_mt);

Formats

Date specifiers

%Y | 2001 | The full proleptic Gregorian year, zero-padded to 4 digits. %C | 20 | The proleptic Gregorian year divided by 100, zero-padded to 2 digits. %y | 01 | The proleptic Gregorian year modulo 100, zero-padded to 2 digits. %m | 07 | Month number (01--12), zero-padded to 2 digits. %b | Jul | Abbreviated month name. Always 3 letters. %B | July | Full month name. Also accepts corresponding abbreviation in parsing. %h | Jul | Same as %b. %d | 08 | Day number (01--31), zero-padded to 2 digits. %e | 8 | Same as %d but space-padded. Same as %_d. %a | Sun | Abbreviated weekday name. Always 3 letters. %A | Sunday | Full weekday name. Also accepts corresponding abbreviation in parsing. %w | 0 | Sunday = 0, Monday = 1, ..., Saturday = 6. %u | 7 | Monday = 1, Tuesday = 2, ..., Sunday = 7. (ISO 8601) %U | 28 | Week number starting with Sunday (00--53), zero-padded to 2 digits. %W | 27 | Same as %U, but week 1 starts with the first Monday in that year instead. %G | 2001 | Same as %Y but uses the year number in ISO 8601 week date. %g | 01 | Same as %y but uses the year number in ISO 8601 week date. %V | 27 | Same as %U but uses the week number in ISO 8601 week date (01--53). %j | 189 | Day of the year (001--366), zero-padded to 3 digits. %D | 07/08/01 | Month-day-year format. Same as %m/%d/%y. %x | 07/08/01 | Locale's date representation (e.g., 12/31/99). %F | 2001-07-08 | Year-month-day format (ISO 8601). Same as %Y-%m-%d. %v | 8-Jul-2001 | Day-month-year format. Same as %e-%b-%Y.

Time specifiers

%H | 00 | Hour number (00--23), zero-padded to 2 digits. %k | 0 | Same as %H but space-padded. Same as %_H. %I | 12 | Hour number in 12-hour clocks (01--12), zero-padded to 2 digits. %l | 12 | Same as %I but space-padded. Same as %_I. %P | am | am or pm in 12-hour clocks. %p | AM | AM or PM in 12-hour clocks. %M | 34 | Minute number (00--59), zero-padded to 2 digits. %S | 60 | Second number (00--60), zero-padded to 2 digits. %f | 026490000 | The fractional seconds (in nanoseconds) since last whole second. %.f | .026490 | Similar to .%f but left-aligned. These all consume the leading dot. %.3f | .026 | Similar to .%f but left-aligned but fixed to a length of 3. %.6f | .026490 | Similar to .%f but left-aligned but fixed to a length of 6. %.9f | .026490000 | Similar to .%f but left-aligned but fixed to a length of 9. %3f | 026 | Similar to %.3f but without the leading dot. %6f | 026490 | Similar to %.6f but without the leading dot. %9f | 026490000 | Similar to %.9f but without the leading dot. %R | 00:34 | Hour-minute format. Same as %H:%M. %T | 00:34:60 | Hour-minute-second format. Same as %H:%M:%S. %X | 00:34:60 | Locale's time representation (e.g., 23:13:48). %r | 12:34:60 AM | Hour-minute-second format in 12-hour clocks. Same as %I:%M:%S %p.

Time zone specifiers

%Z | ACST | Local time zone name. Skips all non-whitespace characters during parsing. %z | +0930 | Offset from the local time to UTC (with UTC being +0000). %:z | +09:30 | Same as %z but with a colon. %#z | +09 | Parsing only: Same as %z but allows minutes to be missing or present.

Date & time specifiers

%c | Sun Jul 8 00:34:60 2001 | Locale's date and time (e.g., Thu Mar 3 23:05:25 2005). %+ | 2001-07-08T00:34:60.026490+09:30 | ISO 8601 / RFC 3339 date & time format. %s | 994518299 | UNIX timestamp, the number of seconds since 1970-01-01 00:00 UTC.

Special specifiers

%t | Literal tab (\t). %n | Literal newline (\n). %% | Literal percent sign.