Macro core_extensions::iter_cloner

macro_rules! iter_cloner {
    (let $ident:ident = $expr:expr) => { ... };
}

Use this macro to create an IterCloner from an IntoIterator (this includes all Iterators).

The resulting variable clones the iterator (that $expr was converted into) every time that you call .into_iter() or iterate over it with a for loop.

Example

Mapping

use core_extensions::iter_cloner;
 
let list = vec!["this", "is", "not", "really", "great"];

let lengths = vec![4, 2, 3, 6, 5];

iter_cloner!(let iter = list.iter().map(|v|v.len()));

assert_eq!(iter.into_iter().collect::<Vec<_>>(), lengths);
assert_eq!(iter.into_iter().collect::<Vec<_>>(), lengths);
assert_eq!(iter.into_iter().collect::<Vec<_>>(), lengths);

Vector

use core_extensions::iter_cloner;

iter_cloner!(let iter = vec![0, 1, 2, 3]);

assert_eq!(iter.into_iter().collect::<Vec<_>>(), [0, 1, 2, 3]);
assert_eq!(iter.into_iter().collect::<Vec<_>>(), [0, 1, 2, 3]);
assert_eq!(iter.into_iter().collect::<Vec<_>>(), [0, 1, 2, 3]);