<h2> <em><span style="color:#c52700">t</span>calc </em> </h2>
A CLI for time arithmetic. Inspired by [when](https://github.com/mitsuhiko/when/tree/main).
Try it [online](https://domenicocinque.github.io/tcalc/).
**Examples:**
* `2023/12/25 - 7d` → subtracts 7 days from December 25, 2023
* `2am + 30m` → adds 30 minutes to 2:00 AM
* `today - 2025/12/25` -> days until December 25, 2025
* `2024/04/27 + 40wd` → adds 40 working days, skipping weekends
## Usage
Run without installing: `cargo run -p tcalc-cli -- "2am + 30m"`
Add holidays to working-day calculations with repeated `--holiday` flags:
`cargo run -p tcalc-cli -- --holiday 2024/04/29 "2024/04/26 + 1wd"`
Or pass a TOML calendar file:
`cargo run -p tcalc-cli -- --calendar holidays.toml "2024/04/26 + 1wd"`
```toml
holidays = ["2024/04/29"]
```
Named calendars are selected with `--calendar-name`:
`cargo run -p tcalc-cli -- --calendar holidays.toml --calendar-name italy "2024/04/26 + 1wd"`
```toml
[italy]
holidays = ["2024/04/25", "2024/04/29"]
```
### Syntax
* Dates use `YYYY/MM/DD` and can include time as `YYYY/MM/DD HH:MM`.
* Times accept 24-hour `HH:MM` or `H[am|pm]` forms (`2pm` → 14:00).
* Keywords: `today`, `tomorrow`, `yesterday`, `now`.
* Durations combine a number with a unit: `y`, `year`, `month`, `day|d`, `workingday|workday|wd`, `hour|h`, `minute|m`, `second|s`.
* Working days skip Saturdays, Sundays, holidays passed with `--holiday`, and holidays loaded from `--calendar`.
* Combine values with `+` and `-`, chaining operations left-to-right (`today - 2h + 30m`).