bounded_integer/

lib.rs

//! This crate provides two types of bounded integer.
//!
//! # Macro-generated bounded integers
//!
//! The [`bounded_integer!`] macro allows you to define your own bounded integer type, given a
//! specific (inclusive) range it inhabits. For example:
//!
//! ```rust
#![cfg_attr(not(feature = "macro"), doc = "# #[cfg(any())] {")]
#![cfg_attr(feature = "step_trait", doc = "# #![feature(step_trait)]")]
//! # use bounded_integer::bounded_integer;
//! bounded_integer! {
//!     struct MyInteger(0, 7);
//! }
//! let num = MyInteger::new(5).unwrap();
//! assert_eq!(num, 5);
#![cfg_attr(not(feature = "macro"), doc = "# }")]
//! ```
//!
//! This macro supports both `struct`s and `enum`s. See the [`examples`] module for the
//! documentation of generated types.
//!
//! # Const generics-based bounded integers
//!
//! You can also create ad-hoc bounded integers via types in this library that use const generics,
//! for example:
//!
//! ```rust
#![cfg_attr(feature = "step_trait", doc = "# #![feature(step_trait)]")]
//! # use bounded_integer::BoundedU8;
//! let num = <BoundedU8<0, 7>>::new(5).unwrap();
//! assert_eq!(num, 5);
//! ```
//!
//! These integers are shorter to use as they don't require a type declaration or explicit name.
//! However due to the limits of const generics, they may not implement some traits –
//! namely [`Default`], bytemuck’s [`Zeroable`] and zerocopy’s [`FromZeros`].
//! Also, unlike their macro counterparts they will not be subject to niche layout optimizations.
//!
//! # `no_std`
//!
//! All the integers in this crate depend only on libcore and so work in `#![no_std]` environments.
//!
//! # Crate Features
//!
//! By default, no crate features are enabled.
//! - `std`: Interopate with `std` — implies `alloc`. Enables the following things:
//!     - An implementation of [`Error`] for [`ParseError`].
//! - `alloc`: Interopate with `alloc`. Has no effect currently.
//! - `macro`: Enable the [`bounded_integer!`] macro.
//! - `arbitrary1`: Implement [`Arbitrary`] for the bounded integers. This is useful when using
//!   bounded integers as fuzzing inputs.
//! - `bytemuck1`: Implement [`Contiguous`] and [`NoUninit`] for all bounded integers,
//!   and [`Zeroable`] for macro-generated bounded integers that support it.
//! - `num-traits02`: Implement [`Bounded`], [`AsPrimitive`], [`FromPrimitive`], [`NumCast`],
//!   [`ToPrimitive`], [`CheckedAdd`], [`CheckedDiv`], [`CheckedMul`], [`CheckedNeg`],
//!   [`CheckedRem`], [`CheckedSub`], [`MulAdd`], [`SaturatingAdd`], [`SaturatingMul`] and
//!   [`SaturatingSub`] for all bounded integers.
//! - `serde1`: Implement [`Serialize`] and [`Deserialize`] for the bounded integers, making sure all
//!   values will never be out of bounds.
//! - `zerocopy`: Implement [`IntoBytes`] and [`Immutable`] for all bounded integers,
//!   [`Unaligned`] for ones backed by `u8` or `i8`,
//!   and [`FromZeros`] for suitable macro-generated ones.
//! - `step_trait`: Implement the [`Step`] trait which allows the bounded integers to be easily used
//!   in ranges. This will require you to use nightly and place `#![feature(step_trait)]` in your
//!   crate root if you use the macro.
//!
//! [`bounded_integer!`]: https://docs.rs/bounded-integer/*/bounded_integer/macro.bounded_integer.html
//! [`examples`]: https://docs.rs/bounded-integer/*/bounded_integer/examples/
//! [`Arbitrary`]: https://docs.rs/arbitrary/1/arbitrary/trait.Arbitrary.html
//! [`Contiguous`]: https://docs.rs/bytemuck/1/bytemuck/trait.Contiguous.html
//! [`NoUninit`]: https://docs.rs/bytemuck/1/bytemuck/trait.NoUninit.html
//! [`Zeroable`]: https://docs.rs/bytemuck/1/bytemuck/trait.Zeroable.html
//! [`Bounded`]: https://docs.rs/num-traits/0.2/num_traits/bounds/trait.Bounded.html
//! [`AsPrimitive`]: https://docs.rs/num-traits/0.2/num_traits/cast/trait.AsPrimitive.html
//! [`FromPrimitive`]: https://docs.rs/num-traits/0.2/num_traits/cast/trait.FromPrimitive.html
//! [`NumCast`]: https://docs.rs/num-traits/0.2/num_traits/cast/trait.NumCast.html
//! [`ToPrimitive`]: https://docs.rs/num-traits/0.2/num_traits/cast/trait.ToPrimitive.html
//! [`CheckedAdd`]: https://docs.rs/num-traits/0.2/num_traits/ops/checked/trait.CheckedAdd.html
//! [`CheckedDiv`]: https://docs.rs/num-traits/0.2/num_traits/ops/checked/trait.CheckedDiv.html
//! [`CheckedMul`]: https://docs.rs/num-traits/0.2/num_traits/ops/checked/trait.CheckedMul.html
//! [`CheckedNeg`]: https://docs.rs/num-traits/0.2/num_traits/ops/checked/trait.CheckedNeg.html
//! [`CheckedRem`]: https://docs.rs/num-traits/0.2/num_traits/ops/checked/trait.CheckedRem.html
//! [`CheckedSub`]: https://docs.rs/num-traits/0.2/num_traits/ops/checked/trait.CheckedSub.html
//! [`MulAdd`]: https://docs.rs/num-traits/0.2/num_traits/ops/mul_add/trait.MulAdd.html
//! [`SaturatingAdd`]: https://docs.rs/num-traits/0.2/num_traits/ops/saturating/trait.SaturatingAdd.html
//! [`SaturatingMul`]: https://docs.rs/num-traits/0.2/num_traits/ops/saturating/trait.SaturatingMul.html
//! [`SaturatingSub`]: https://docs.rs/num-traits/0.2/num_traits/ops/saturating/trait.SaturatingSub.html
//! [`Serialize`]: https://docs.rs/serde/1/serde/trait.Serialize.html
//! [`Deserialize`]: https://docs.rs/serde/1/serde/trait.Deserialize.html
//! [`IntoBytes`]: https://docs.rs/zerocopy/0.8/zerocopy/trait.IntoBytes.html
//! [`FromZeros`]: https://docs.rs/zerocopy/0.8/zerocopy/trait.FromZeros.html
//! [`Immutable`]: https://docs.rs/zerocopy/0.8/zerocopy/trait.Immutable.html
//! [`Unaligned`]: https://docs.rs/zerocopy/0.8/zerocopy/trait.Unaligned.html
//! [`Step`]: https://doc.rust-lang.org/nightly/core/iter/trait.Step.html
//! [`Error`]: https://doc.rust-lang.org/stable/std/error/trait.Error.html
//! [`ParseError`]: https://docs.rs/bounded-integer/*/bounded_integer/struct.ParseError.html
#![warn(clippy::pedantic, rust_2018_idioms, unused_qualifications)]
#![allow(clippy::items_after_statements, clippy::missing_errors_doc)]
#![cfg_attr(feature = "step_trait", feature(step_trait))]
#![cfg_attr(feature = "__doc", feature(doc_auto_cfg))]
#![no_std]

#[cfg(feature = "std")]
extern crate std;

#[cfg(feature = "alloc")]
#[cfg(test)]
extern crate alloc;

mod types;
pub use types::*;

#[cfg(feature = "macro")]
mod r#macro;

mod parse;
pub use parse::{ParseError, ParseErrorKind};

mod prim_int;
pub use prim_int::TryFromError;

// Not public API.
#[doc(hidden)]
pub mod __private {
    #[cfg(feature = "arbitrary1")]
    pub use ::arbitrary1;

    #[cfg(feature = "bytemuck1")]
    pub use ::bytemuck1;

    #[cfg(feature = "num-traits02")]
    pub use ::num_traits02;

    #[cfg(feature = "serde1")]
    pub use ::serde1;

    #[cfg(feature = "zerocopy")]
    pub use ::zerocopy;

    #[cfg(feature = "macro")]
    pub use bounded_integer_macro::bounded_integer as proc_macro;

    // Helper to allow type-driven dispatch in `const fn`.
    pub struct Dispatch<T>(T, core::convert::Infallible);

    pub trait NewWrapping<T> {
        #[doc(hidden)]
        fn new_wrapping(n: T) -> Self;
    }

    pub use crate::parse::{error_above_max, error_below_min};
    pub use crate::prim_int::{Signed, Unsigned, Wide, try_from_error};

    feature_flags! { $
        __cfg_arbitrary1 "arbitrary1",
        __cfg_bytemuck1 "bytemuck1",
        __cfg_num_traits02 "num-traits02",
        __cfg_serde1 "serde1",
        __cfg_step_trait "step_trait",
        __cfg_zerocopy "zerocopy",
    }
    macro_rules! feature_flags {
        ($d:tt $($cfg:ident $flag:literal,)*) => { $(
            #[macro_export]
            #[cfg(feature = $flag)]
            #[doc(hidden)]
            #[cfg(not(feature = "__doc"))]
            macro_rules! $cfg {
                ($d ($tt:tt)*) => { $d ($tt)* };
            }
            // If the `__doc` feature flag is enabled, we are building for the current crate, and
            // thus we forward the `cfg` so that `doc_auto_cfg` sees it.
            #[macro_export]
            #[cfg(feature = $flag)]
            #[doc(hidden)]
            #[cfg(feature = "__doc")]
            macro_rules! $cfg {
                ($d ($item:item)*) => { $d (#[cfg(feature = $flag)] $item)* };
            }
            #[macro_export]
            #[cfg(not(feature = $flag))]
            #[doc(hidden)]
            macro_rules! $cfg {
                ($d ($tt:tt)*) => {};
            }
            pub use $cfg;
        )* };
    }
    use feature_flags;
}

#[cfg(feature = "__doc")]
pub mod examples;

#[test]
#[cfg(feature = "macro")]
// Don’t test on Nightly because the output is different to stable.
#[cfg(not(feature = "__doc"))]
fn ui() {
    let t = trybuild::TestCases::new();
    t.pass("tests/force_build.rs");
    t.compile_fail("ui/*.rs");
}

mod unsafe_api;