Trait Iterator 

pub trait Iterator {
    type Item;

    // Required method
    fn next(&mut self) -> Option<Self::Item>;
}

Available on crate feature ferrocene_certified only.

A trait for dealing with iterators.

This is the main iterator trait. For more about the concept of iterators generally, please see the module-level documentation. In particular, you may want to know how to implement Iterator.

Required Associated Types

type Item

The type of the elements being iterated over.

Required Methods

fn next(&mut self) -> Option<Self::Item>

Advances the iterator and returns the next value.

Returns None when iteration is finished. Individual iterator implementations may choose to resume iteration, and so calling next() again may or may not eventually start returning Some(Item) again at some point.

Examples

let a = [1, 2, 3];

let mut iter = a.into_iter();

// A call to next() returns the next value...
assert_eq!(Some(1), iter.next());
assert_eq!(Some(2), iter.next());
assert_eq!(Some(3), iter.next());

// ... and then None once it's over.
assert_eq!(None, iter.next());

// More calls may or may not return `None`. Here, they always will.
assert_eq!(None, iter.next());
assert_eq!(None, iter.next());

Implementors