Module format

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

pub use strftime::StrftimeItems;

Modules

strftime

strftime/strptime-inspired date and time formatting syntax.

Structs

DelayedFormat

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.

InternalFixed

An opaque type representing fixed-format item types for internal uses only.

InternalNumeric

An opaque type representing numeric item types for internal uses only.

OffsetFormat

Type for specifying the format of UTC offsets.

ParseError

An error from the parse function.

Parsed

Parsed parts of date and time. There are two classes of methods:

Enums

Colons

The separator between hours and minutes in an offset.

Fixed

Fixed-format item types.

Item

A single formatting item. This is used for both formatting and parsing.

Numeric

Numeric item types. They have associated formatting width (FW) and parsing width (PW).

OffsetPrecision

The precision of an offset from UTC formatting item.

Pad

Padding characters for numeric items.

ParseErrorKind

The category of parse error

SecondsFormat

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

parse

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.

parse_and_remainder

Tries to parse given string into parsed with given formatting items. Returns Ok with a slice of the unparsed remainder.

Type Aliases

ParseResult

Same as Result<T, ParseError>.