TL;DR

Some notes about the time sub-command in Romeo.

As a small note to future me, and to excercise my muscle memory a bit, some usage examples on using the time sub-command.

The main goal is to transform… time across different representations: epoch, ISO-8601(ish) strings, Active Directory monstrous integers.

It aims at being useful while not taking itself too seriously, so beware: anything before the start of the Unix epoch (1970-01-01T00:00:00) or sufficiently ahead in the future is officially unsupported.

I played a bit with the interface, eventually settling on a dwim default where it’s possible to specify the input format directly (defaulting to epochs if it’s just a bunch of digits). So…

$ romeo time iso:2023-04-01 1680300000 ad:133247736000000000
2023-04-01T00:00:00+0200
2023-04-01T00:00:00+0200
2023-04-01T00:00:00+0200

As it’s clear, the output defaults to my favourite flavor of ISO-8601 format. This is in the spirit that most of the time I want to figure out what an epoch or an AD time mean in my local time.

It’s possible that some different conversion is needed, though. Especially when we’re starting from an ISO-8601 date/datetime, right? It’s of course possible to set a differnet target format:

$ romeo time iso:2023-04-01 -t epoch
1680300000

$ romeo time iso:2023-04-01 -output-format ad
133247736000000000

# Look! No offset!
$ romeo time iso:2023-04-01 -t gm
2023-03-31T22:00:00+0000

There’s also some rudimentary arithmetic capability, where it’s possible to add offsets either directly when providing an input:

$ romeo time iso:2023-04-01+2w-1d
2023-04-14T00:00:00+0200

or using the specific offset option -D/--offset:

$ romeo time iso:2023-04-01 -D +2w-1d
2023-04-14T00:00:00+0200

What’s the difference? Well, the option is applied to all inputs, so it’s useful if we want to apply a specific offset to a bunch of input dates:

$ romeo time iso:2023-04-01 1680300000 ad:133247736000000000 -D +2w-1d
2023-04-14T00:00:00+0200
2023-04-14T00:00:00+0200
2023-04-14T00:00:00+0200

The other alternative is more a shorthand to set a specific point in time, so to say. This is because there’s more to the do what I mean interface, like using words like now, today, yesterday, and tomorrow:

$ romeo time now today yesterday tomorrow
2023-04-07T17:51:36+0200
2023-04-07T00:00:00+0200
2023-04-06T00:00:00+0200
2023-04-08T00:00:00+0200

This makes it easy to express the day before yesterday (ereyesterday seemed a bit too archaic) or the day after tomorrow:

$ romeo time yesterday-1d today-2d today+2d tomorrow+1d
2023-04-05T00:00:00+0200
2023-04-05T00:00:00+0200
2023-04-09T00:00:00+0200
2023-04-09T00:00:00+0200

OK, I hope this will be a useful refresher… bye bye, future me!

Everyone else stay safe!