Author: Bryce Campbell
Description: A single trait library that adds an iterator method allowing one to easily count up elements matching a particular condition.
License: See LICENSE
-
- 0.1.1
-
Released June 7, 2021
Allows comparison booleans in closure.
-
- 0.1
Released June 6, 2021
Initial release.
This library has only been tested with Rust 1.51.0 on macOS Big Sur, but should work on any platform.
I like dabbling in programming from time to time, and one day I tried to make a Rust equivalent of this project, to help me gain more experience with Rust.
While I could figure out most things, I had a bit of trouble with how I was implementing things, such as a counting method to determine how many times a number occurred.
Even though I could create a function that took the data and a number to look for, it seemed to be not quite as nice as the extension I wrote for the Swift variant, which worked for all Sequences that had items that conformed to Equatable.
As a result, I decided to look into creating an extension on Iterator in Rust, so that I could do something like this in Rust:
sequence.count { $0 == number }
Not only did I kind of succeed when writing the code for the library, but it gave me a good chance to see how to make a ttrait extension and creating a library right in Rust.
While this library does not provide the same simplicity as the Swift code seen above, it still provides the same convenience, which is what I needed.
To use this library, add the following to the Cargo.toml file:
[dependencies] count_where = "0.1.1"
Afterwards, it is as simple as putting the following in the source file needing the method:
use count_where::CountWhere;
You can then use code like this to do your counting:
fn main() {
let numbers = [5, 5, 5, 2, 1];
let number = 5
println!("{} appears {} times", number, numbers.iter().count_where(|n| **n == number));
}
Because n is of type &&T, it needs to be dereferenced as seen above, in order to make the comparison.
This could change in the future, which I would have liked to do, but because I am not as experienced with Rust as I am with Swift, this will be something I need to live with.
If you would like to contribute to this library, feel free to create a fork and send your modifications.
One thing that I would really like is for the provided function to usable in a way lie the filter method, which is utilitized like this:
fn main() {
let numbers = [5, 5, 5, 2, 1];
let filtered_numbers = numbers.iter().filter(|n| n == 5);
println!("{}", filtered_numbers);
}
Due to my experience with Rust being limited, in comparison to Swift, I cannot provide that much support, so expect to be on your own.
However, I can try to check things out, so feel free contact me at the email below.