Calculate the time interval between two DateTime instances and output the result in years plus months plus days plus hours plus minutes plus seconds plus nanoseconds (instead of representing the same duration in different units). This library is useful for lifespan check and age calculation.
```rust use chrono::prelude::*;
use datedifferencer::{datediff, datetimediff, adddatetime_diff};
let a = Local.withymdandhms(2022, 4, 6, 0, 0, 0).unwrap(); let b = Local.withymdandhms(2023, 6, 9, 1, 0, 0).unwrap();
println!("{:?}", date_diff(a, b)); /* { "years": 1, "months": 2, "days": 3 } */
println!("{:?}", datetimediff(a, b)); /* { "years": 1, "months": 2, "days": 3, "hours": 1, "minutes": 0, "seconds": 0, "nanoseconds": 0 } */
println!("{}", adddatetimediff(a, &datetime_diff(a, b)).unwrap()); // the same as b ```
This library can handle leap years and odd/even number of days in a month correctly. The result of following code is a bit confusing but reasonable.
```rust use chrono::prelude::*;
use datedifferencer::datediff;
let a = Local.withymdandhms(2020, 2, 27, 0, 0, 0).unwrap(); let b = Local.withymdandhms(2021, 3, 1, 0, 0, 0).unwrap();
println!("{:?}", date_diff(a, b)); /* { "years": 1, "months": 0, "days": 2 }
Explanation: 1. 2020-02-27 + 1 year -> 2021-02-27 2. 2021-02-27 + 2 days -> 2021-03-01 (2021-02 has 28 days) */
println!("{:?}", date_diff(b, a)); /* { "years": -1, "months": 0, "days": -3 }
Explanation: 1. 2021-03-01 - 1 year -> 2020-03-01 2. 2020-03-01 - 3 days -> 2020-02-27 (2020-02 has 29 days) */ ```
https://crates.io/crates/date-differencer
https://docs.rs/date-differencer