public/subjects/roman_numbers_iter

roman_numbers_iter

Instructions

Implement the IntoIterator trait for the RomanNumber type to enable using a for loop notation. This implementation must allow taking ownership, borrowing and borrowing mutably.

1. Taking ownership (this consumes the RomanNumber)

for digit in number {
	...
}

2. Borrowing immutably (this preserves the RomanNumber)

	for digit in &number {

	}

3. Borrowing mutably (this allow you to modify the RomanNumber without having to return the ownership)

	for digit in &mut number {

	}

Notions

• https://doc.rust-lang.org/std/iter/trait.IntoIterator.html
• https://doc.rust-lang.org/std/iter/index.html

Expected Functions

use roman_numbers::{RomanDigit, RomanNumber};

impl IntoIterator for &RomanNumber {
}

impl IntoIterator for &mut RomanNumber {
}

impl IntoIterator for RomanNumber {
}

Usage

Here is a program to test your function.

use roman_numbers::RomanNumber;

fn main() {
	let number = RomanNumber::from(15);

	for digit in &number {
		println!("{:?}", digit);
	}
	println!("{:?}", number);
}

And its output

$ cargo run
RomanNumber([X, X, X, I, I])
RomanNumber([I, X])
RomanNumber([X, L, V])
RomanNumber([Nulla])
$