utc2k 0.11.2

A fast and lean UTC date/time library concerned only with happenings in this century (2000-2099).
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# UTC2K

[![docs.rs](https://img.shields.io/docsrs/utc2k.svg?style=flat-square&label=docs.rs)](https://docs.rs/utc2k/)
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UTC2K is a fast and lean date/time library that only cares about UTC happenings in _this century_ (between `2000-01-01 00:00:00` and `2099-12-31 23:59:59`).

With that very significant constraint in mind, UTC2K can:

* Convert to/from Unix timestamps (`u32`);
* Convert to/from date strings of the `YYYY-MM-DD` and `YYYY-MM-DD hh:mm:ss` varieties;
* Perform addition/subtraction (in seconds), checked or saturating;
* Calculate the date's ordinal;
* Calculate the number of seconds from midnight;

That's it!

Compared to more robust libraries like [`chrono`](https://crates.io/crates/chrono) and [`time`](https://crates.io/crates/time), UTC2K can be magnitudes faster, particularly in regards to string parsing and printing.

This library is still a work in progress and there is certainly room to improve performance further.

If you have any suggestions for improvement, feel free to open [an issue](https://github.com/Blobfolio/utc2k/issues) on Github!



## Examples

The main date object is `Utc2k`.

```rust
use utc2k::Utc2k;
use std::convert::TryFrom;

let date = Utc2k::default(); // 2000-01-01 00:00:00
let date = Utc2k::now(); // The current time.
let date = Utc2k::from(4_102_444_799_u32); // 2099-12-31 23:59:59
let date = Utc2k::new(2010, 10, 31, 15, 30, 0); // 2010-10-31 15:30:00

// String parsing is fallible, but flexible. So long as the numbers we
// need are in the right place, it will be fine. (At least, it won't error
// out; if the date string is trying to communicate a time zone, that won't
// be listened to.)
assert!(Utc2k::try_from("2099-12-31 23:59:59").is_ok()); // Fine.
assert!(Utc2k::try_from("2099-12-31T23:59:59.0000Z").is_ok()); // Also fine.
assert!(Utc2k::try_from("January 1, 2010 @ Eleven O'Clock").is_err()); // Nope!
```

There is also `FmtUtc2k`, used for string representation.

```rust
use utc2k::{FmtUtc2k, Utc2k};
use std::convert::TryFrom;

// You can generate it from an existing Utc2k with either:
assert_eq!(Utc2k::default().formatted(), FmtUtc2k::from(Utc2k::default()));

// You could also skip `Utc2k` and seed directly from a timestamp or date/time
// string.
let fmt = FmtUtc2k::from(4_102_444_799_u32);
let fmt = FmtUtc2k::try_from("2099-12-31 23:59:59").unwrap();
```

Once you have a `FmtUtc2k`, you can turn it into a string with:

```rust
use utc2k::{FmtUtc2k, Utc2k};
use std::borrow::Borrow;

let fmt = FmtUtc2k::from(4_102_444_799_u32);

let s: &str = &fmt;
let s: &str = fmt.as_ref();
let s: &str = fmt.as_str();
let s: &str = fmt.borrow();
```



## Optional Crate Features

* `local`: Enables the `LocalOffset` struct. Refer to the documentation for important caveats and limitations.
* `serde`: Enables serialization/deserialization support.



## Installation

Add `utc2k` to your `dependencies` in `Cargo.toml`, like:

```
[dependencies]
utc2k = "0.11.*"
```