#iterator #enumerate #step #trait-extension #indexer-iterator

iter-index

More flexible alternative to Iterator's enumerate() method

3 releases (1 stable)

new 1.0.0 May 7, 2025
0.1.1 Jan 18, 2025
0.1.0 Jan 17, 2025

#722 in Rust patterns

Download history 220/week @ 2025-01-16 2/week @ 2025-01-30 6/week @ 2025-02-06 1/week @ 2025-02-13 1/week @ 2025-02-20 4/week @ 2025-02-27

167 downloads per month

MIT/Apache

15KB
158 lines

crate documentation license license

iter-index crate

This is a simple extension trait that provides a more flexible alternative to the iterator's method enumerate(). It allows to:

  • use a custom type for the index with index::<T>()
  • define a custom start value with index_start::<T>(start: T)
  • define a custom step value with index_step::<T>(start: T, step: T).

Examples

use iter_index::IndexerIterator;

let mut map = HashMap::<u8, &str>::new();
for (k, v) in vec!["a", "b", "c"].into_iter().index() {
    map.insert(k, v);
}
assert_eq!(map, HashMap::from([(0_u8, "a"), (1_u8, "b"), (2_u8, "c")]));
let items = vec!["a", "b", "c"];
let mut result = items.into_iter().index_start::<u8>(97);

assert_eq!(result.next(), Some((97_u8, "a")));
assert_eq!(result.next(), Some((98_u8, "b")));
assert_eq!(result.next(), Some((99_u8, "c")));
assert_eq!(result.next(), None);
let items = vec!["a", "b", "c"];
let mut result = items.into_iter().index_step::<u32>(100, 10);

assert_eq!(result.next(), Some((100_u32, "a")));
assert_eq!(result.next(), Some((110_u32, "b")));
assert_eq!(result.next(), Some((120_u32, "c")));
assert_eq!(result.next(), None);

License

This code is licensed under either MIT License or Apache License 2.0.

No runtime deps