Crate strftime

This crate provides a Ruby 3.1.2 compatible strftime function, which formats time according to the directives in the given format string.

The directives begin with a percent % character. Any text not listed as a directive will be passed through to the output string.

Each directive consists of a percent % character, zero or more flags, optional minimum field width, optional modifier and a conversion specifier as follows:

%<flags><width><modifier><conversion>

Usage

The various strftime functions in this crate take a generic time parameter that implements the Time trait.

Format Specifiers

Flags

Flag	Description
-	Use left padding, ignoring width and removing all other padding options in most cases.
_	Use spaces for padding.
0	Use zeros for padding.
^	Convert the resulting string to uppercase.
#	Change case of the resulting string.

Width

The minimum field width specifies the minimum width.

Modifiers

The modifiers are E and O. They are ignored.

Specifiers

Specifier	Example	Description
%Y	-2001	Year with century if provided, zero-padded to at least 4 digits plus the possible negative sign.
%C	-21	Year / 100 using Euclidean division, zero-padded to at least 2 digits.
%y	99	Year % 100 in 00..=99, using Euclidean remainder, zero-padded to 2 digits.
%m	01	Month of the year in 01..=12, zero-padded to 2 digits.
%B	July	Locale independent full month name.
%b, %h	Jul	Locale independent abbreviated month name, using the first 3 letters.
%d	01	Day of the month in 01..=31, zero-padded to 2 digits.
%e	1	Day of the month in 1..=31, blank-padded to 2 digits.
%j	001	Day of the year in 001..=366, zero-padded to 3 digits.
%H	00	Hour of the day (24-hour clock) in 00..=23, zero-padded to 2 digits.
%k	0	Hour of the day (24-hour clock) in 0..=23, blank-padded to 2 digits.
%I	01	Hour of the day (12-hour clock) in 01..=12, zero-padded to 2 digits.
%l	1	Hour of the day (12-hour clock) in 1..=12, blank-padded to 2 digits.
%P	am	Lowercase meridian indicator ("am" or "pm").
%p	AM	Uppercase meridian indicator ("AM" or "PM").
%M	00	Minute of the hour in 00..=59, zero-padded to 2 digits.
%S	00	Second of the minute in 00..=60, zero-padded to 2 digits.
%L	123	Truncated fractional seconds digits, with 3 digits by default. Number of digits is specified by the width field.
%N	123456789	Truncated fractional seconds digits, with 9 digits by default. Number of digits is specified by the width field.
%z	+0200	Zero-padded signed time zone UTC hour and minute offsets (+hhmm).
%:z	+02:00	Zero-padded signed time zone UTC hour and minute offsets with colons (+hh:mm).
%::z	+02:00:00	Zero-padded signed time zone UTC hour, minute and second offsets with colons (+hh:mm:ss).
%:::z	+02	Zero-padded signed time zone UTC hour offset, with optional minute and second offsets with colons (+hh[:mm[:ss]]).
%Z	CEST	Platform-dependent abbreviated time zone name.
%A	Sunday	Locale independent full weekday name.
%a	Sun	Locale independent abbreviated weekday name, using the first 3 letters.
%u	1	Day of the week from Monday in 1..=7, zero-padded to 1 digit.
%w	0	Day of the week from Sunday in 0..=6, zero-padded to 1 digit.
%G	-2001	Same as %Y, but using the ISO 8601 week-based year. 1
%g	99	Same as %y, but using the ISO 8601 week-based year. 1
%V	01	ISO 8601 week number in 01..=53, zero-padded to 2 digits. 1
%U	00	Week number from Sunday in 00..=53, zero-padded to 2 digits. The week 1 starts with the first Sunday of the year.
%W	00	Week number from Monday in 00..=53, zero-padded to 2 digits. The week 1 starts with the first Monday of the year.
%s	86400	Number of seconds since 1970-01-01 00:00:00 UTC, zero-padded to at least 1 digit.
%n	\n	Newline character '\n'.
%t	\t	Tab character '\t'.
%%	%	Literal '%' character.
%c	Sun Jul 8 00:23:45 2001	Date and time, equivalent to "%a %b %e %H:%M:%S %Y".
%D, %x	07/08/01	Date, equivalent to "%m/%d/%y".
%F	2001-07-08	ISO 8601 date, equivalent to "%Y-%m-%d".
%v	8-JUL-2001	VMS date, equivalent to "%e-%^b-%4Y".
%r	12:23:45 AM	12-hour time, equivalent to "%I:%M:%S %p".
%R	00:23	24-hour time without seconds, equivalent to "%H:%M".
%T, %X	00:23:45	24-hour time, equivalent to "%H:%M:%S".

---

1. %G, %g, %V: Week 1 of ISO 8601 is the first week with at least 4 days in that year. The days before the first week are in the last week of the previous year. ↩

Modules

• buffered
  Provides a strftime implementation using a format string with arbitrary bytes, writing to a provided byte slice.
• bytesalloc
  Provides a strftime implementation using a format string with arbitrary bytes, writing to a newly allocated Vec.
• fmt
  Provides a strftime implementation using a UTF-8 format string, writing to a core::fmt::Write object.
• stringalloc
  Provides a strftime implementation using a UTF-8 format string, writing to a newly allocated String.

Enums

• Error
  Error type returned by the strftime functions.

Constants

• ASCTIME_FORMAT_STRING
  Format string used by Ruby Time#asctime method.

Traits

• Time
  Common methods needed for formatting time.