ForEach trait and for_each! macro

ForEach trait and for_each! macro allow you to use iterator inside iteration loop, which is not posible when using for-in loop.

lib.rs:

ForEach trait and for_each! macro allow you to use iterator inside iteration loop, which is not posible when using for-in loop.

Examples

let mut iter = 0..999;
iter.foreach(|item, iter| {
    println!("item: {}", item);
    println!("next: {:?}", iter.next());
});

use foreach::Continue::*;
let mut iter = 0..999;
iter.foreach(|item, iter| {
    println!("item: {}", item);
    println!("next: {:?}", iter.next());
    if item > 10 {
        return Break;
    } else {
        return ().into();
    }
});

let mut iter = 0..999;
for_each!(item in iter {
    println!("item: {}", item);
    println!("next: {:?}", iter.next());
    if item > 10 {
        break;
    }
});