chrono

Module format

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Expand description

Formatting (and parsing) utilities for date and time.

This module provides the common types and routines to implement, for example, DateTime::format or DateTime::parse_from_str methods. For most cases you should use these high-level interfaces.

Internally the formatting and parsing shares the same abstract formatting items, which are just an Iterator of the Item type. They are generated from more readable format strings; currently Chrono supports a built-in syntax closely resembling C’s strftime format. The available options can be found here.

§Example

use chrono::{NaiveDateTime, TimeZone, Utc};

let date_time = Utc.with_ymd_and_hms(2020, 11, 10, 0, 1, 32).unwrap();

let formatted = format!("{}", date_time.format("%Y-%m-%d %H:%M:%S"));
assert_eq!(formatted, "2020-11-10 00:01:32");

let parsed = NaiveDateTime::parse_from_str(&formatted, "%Y-%m-%d %H:%M:%S")?.and_utc();
assert_eq!(parsed, date_time);

Re-exports§

Modules§

  • strftime/strptime-inspired date and time formatting syntax.

Structs§

  • A temporary object which can be used as an argument to format! or others. This is normally constructed via format methods of each date and time type.
  • An opaque type representing fixed-format item types for internal uses only.
  • An opaque type representing numeric item types for internal uses only.
  • Type for specifying the format of UTC offsets.
  • An error from the parse function.
  • A type to hold parsed fields of date and time that can check all fields are consistent.

Enums§

  • The separator between hours and minutes in an offset.
  • Fixed-format item types.
  • A single formatting item. This is used for both formatting and parsing.
  • Numeric item types. They have associated formatting width (FW) and parsing width (PW).
  • The precision of an offset from UTC formatting item.
  • Padding characters for numeric items.
  • The category of parse error
  • Specific formatting options for seconds. This may be extended in the future, so exhaustive matching in external code is not recommended.

Functions§

  • formatDeprecated
    Tries to format given arguments with given formatting items. Internally used by DelayedFormat.
  • format_itemDeprecated
    Formats single formatting item
  • Tries to parse given string into parsed with given formatting items. Returns Ok when the entire string has been parsed (otherwise parsed should not be used). There should be no trailing string after parsing; use a stray Item::Space to trim whitespaces.
  • Tries to parse given string into parsed with given formatting items. Returns Ok with a slice of the unparsed remainder.

Type Aliases§