Reverse strftime

Strftime directives on the command line. Pass in a date, get back a strftime string.

Installation

Must be installed globally (so it's available from the command line).

``bash


yarn

yarn global add reverse-strftime

or npm

npm i -g reverse-strftime
`

Usage

In the console, input your desired date format:

strftime [date string] (options)

`bash
strftime Saturday January 1, 2020


➜ %A %B %e, %Y

strftime Sat. Jan. 01, 20


➜ %a. %b. %d %y

strftime 4/4/21


➜ %m/%e/%y

strftime 4-04-2021


➜ %m-%d-%Y

strftime Mon. January 1, 2044 14:40:45


➜ %a. %B %e, %Y %H:%M:%S

strftime 4/4/4444 4:40:45 am


➜ %m/%e/%Y %l:%M:%S %P


`

$3

By default, the input string is parsed using the system locale. See the and options below for using locales other than your own.

`bash


System locale: es-MX

strftime Thursday, 20 May 2021 01:20:12

➜ %A, %d %B %Y %H:%M:%S

`

Options

$3

(Requires Node > v12)

Indicate if your input order differs from the system locale's. e.g. You're in the US, but are putting the day first.

strftime [datestring] -l --locale

`bash


System locale => en-US (M/D/YYYY)

Let's generate a string for en-GB (D/MM/YYYY)

strftime Mon. 31/12/1999 -l en-GB

➜ %a. %d/%m/%Y

Same input without padding a locale will give incorrect output.

strftime Mon. 31/12/1999

➜ %a. %m/%d/%Y (Nope)

`

$3

Auto generate strftime string.
Optionally pass in a locale (see above) to generate for another locale.

strftime -a --auto

`bash


locale: en-US

strftime -a


➜ %A, %B %d, %Y at %H:%M:%S %p

➜ Monday, May 17, 2021 at 23:34:26 PM

Let's autogenerate for another locale

strftime -a -l en-GB

➜ %A, %d %B %Y at %H:%M:%S

`

$3

When autogenerating, prefer short-format.

strftime -a -s --short

`bash
strftime -a -s


➜ %m/%d/%y, %H:%M %p


`

Reference

Use the reference command to log all the strftime keys.

strftime reference|ref

`bash
strftime ref

Logs:

➜ Weekday

%A Sunday

%a Sun

#

➜ Month

%B August

%b Aug

%m 08

...
`

Usage Notes

$3

As usual, you can combine commands

`bash
strftime -asl en-GB


➜ %d/%m/%Y, %H:%M


`

$3

The date does not have to be accurate, only recognizable. i.e. you don't have to think about the date (just the format).

`bash


New Year's Eve in 1999 was actually a Friday,

but this still prints the correct strftime:

strftime Sunday December 31, 1999

➜ %A %B %d, %Y

`

$3

reverse-strftime mostly expects full dates, or at least partial dates in order.

`bash


This is fine

strftime June 1


➜ %B %e

But it'll bonk if time is added and

year is skipped:

strftime June 1 4pm

➜ %B %e %y%P

``