#iterator #enumerate #trait-extension

iter-index

More flexible alternative to Iterator's enumerate() method

2 releases

new 0.1.1 Jan 18, 2025
0.1.0 Jan 17, 2025

#573 in Rust patterns

37 downloads per month

MIT/Apache

15KB
149 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 items = vec!["a", "b", "c"];
let mut result = items.into_iter().index::<i32>();

assert_eq!(result.next(), Some((0_i32, "a")));
assert_eq!(result.next(), Some((1_i32, "b")));
assert_eq!(result.next(), Some((2_i32, "c")));
assert_eq!(result.next(), None);
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