Crate count_where

count_where adds a method to the Iterator trait that allows one to count the numbers of items matching a given predicate, much like a custom function in Swift that filters a sequence and return the count.

Quick Start

The easiest way to get things working, after adding the crate as a dependency would be like this:

use count_where::CountWhere;
 
fn main() {
 let numbers = [5, 5, 5, 2, 1];
 let number = 5;
 println!("{} appears {} times.", number, numbers.iter().count_where(|n| **n == number));
}

The above goes through a specified array and looks for each instance that the number is 5 and displays that to the user.

Traits

CountWhere

trait extension that adds count_where functionality to iterators.