#derive #enums #iterator #derive-enums #no-alloc

macro no-std iter-enum

#[derive(Iterator, DoubleEndedIterator, ExactSizeIterator, Extend)] for enums

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1.2.0 Jan 16, 2025
1.1.3 Jan 27, 2024
1.1.1 Jun 29, 2023
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#1994 in Rust patterns

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Apache-2.0 OR MIT

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iter-enum

crates.io docs.rs license msrv github actions

#[derive(Iterator, DoubleEndedIterator, ExactSizeIterator, FusedIterator, Extend)] for enums.

Usage

Add this to your Cargo.toml:

[dependencies]
iter-enum = "1"

Examples

use iter_enum::{Iterator, DoubleEndedIterator, ExactSizeIterator, FusedIterator, Extend};

#[derive(Iterator, DoubleEndedIterator, ExactSizeIterator, FusedIterator, Extend)]
enum Either<A, B> {
    A(A),
    B(B),
}

fn foo(x: i32) -> impl Iterator<Item = i32> {
    if x > 0 {
        Either::A(x..=0)
    } else {
        Either::B(Some(x).into_iter())
    }
}

See auto_enums crate for how to automate patterns like this.

Supported traits

Optional features

  • rayon
    • Enable to use #[derive(ParallelIterator, IndexedParallelIterator, ParallelExtend)].
  • auto_enums: A library for to allow multiple return types by automatically generated enum.
  • derive_utils: A procedural macro helper for easily writing derives macros for enums.
  • io-enum: #[derive(Read, Write, Seek, BufRead)] for enums.

License

Licensed under either of Apache License, Version 2.0 or MIT license at your option.

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.

Dependencies

~130–470KB
~11K SLoC