| bitflags |
| ======== |
| |
| [![Rust](https://github.com/bitflags/bitflags/workflows/Rust/badge.svg)](https://github.com/bitflags/bitflags/actions) |
| [![Latest version](https://img.shields.io/crates/v/bitflags.svg)](https://crates.io/crates/bitflags) |
| [![Documentation](https://docs.rs/bitflags/badge.svg)](https://docs.rs/bitflags) |
| ![License](https://img.shields.io/crates/l/bitflags.svg) |
| |
| `bitflags` generates flags enums with well-defined semantics and ergonomic end-user APIs. |
| |
| You can use `bitflags` to: |
| |
| - provide more user-friendly bindings to C APIs where flags may or may not be fully known in advance. |
| - generate efficient options types with string parsing and formatting support. |
| |
| You can't use `bitflags` to: |
| |
| - guarantee only bits corresponding to defined flags will ever be set. `bitflags` allows access to the underlying bits type so arbitrary bits may be set. |
| - define bitfields. `bitflags` only generates types where set bits denote the presence of some combination of flags. |
| |
| - [Documentation](https://docs.rs/bitflags) |
| - [Specification](https://github.com/bitflags/bitflags/blob/main/spec.md) |
| - [Release notes](https://github.com/bitflags/bitflags/releases) |
| |
| ## Usage |
| |
| Add this to your `Cargo.toml`: |
| |
| ```toml |
| [dependencies] |
| bitflags = "2.6.0" |
| ``` |
| |
| and this to your source code: |
| |
| ```rust |
| use bitflags::bitflags; |
| ``` |
| |
| ## Example |
| |
| Generate a flags structure: |
| |
| ```rust |
| use bitflags::bitflags; |
| |
| // The `bitflags!` macro generates `struct`s that manage a set of flags. |
| bitflags! { |
| /// Represents a set of flags. |
| #[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)] |
| struct Flags: u32 { |
| /// The value `A`, at bit position `0`. |
| const A = 0b00000001; |
| /// The value `B`, at bit position `1`. |
| const B = 0b00000010; |
| /// The value `C`, at bit position `2`. |
| const C = 0b00000100; |
| |
| /// The combination of `A`, `B`, and `C`. |
| const ABC = Self::A.bits() | Self::B.bits() | Self::C.bits(); |
| } |
| } |
| |
| fn main() { |
| let e1 = Flags::A | Flags::C; |
| let e2 = Flags::B | Flags::C; |
| assert_eq!((e1 | e2), Flags::ABC); // union |
| assert_eq!((e1 & e2), Flags::C); // intersection |
| assert_eq!((e1 - e2), Flags::A); // set difference |
| assert_eq!(!e2, Flags::A); // set complement |
| } |
| ``` |
| |
| ## Rust Version Support |
| |
| The minimum supported Rust version is documented in the `Cargo.toml` file. |
| This may be bumped in minor releases as necessary. |