Exint - Exotic Integer Types

A pure Rust implementation of generic signed and unsigned integers.

This crate provides the no_std-compatible types int<N> and uint<N>, which mimic the behavior and API of the core integer primitives while supporting fixed-width values of arbitrary precision.

[dependencies]
exint = "0.1.0"

Basic example

use exint::primitive::u24;

fn main() {
  let a: u24 = u24::from(123_u16);
  let b: u24 = u24::from(456_u16);
  let c: u24 = u24::from(10_u16);

  println!("d = {}", a + b);
  println!("e = {}", a.wrapping_sub(b));
  println!("f = {}", u24::MAX - (c >> 1_u32));
}

Literals

Since there is no way to define your own literal format in Rust, exint provides a simple procedural macro.

The above example can be re-written as the following:

use exint::primitive::u24;

fn main() {
  exint::uint! {
    let a: u24 = 123_u24;
    let b: u24 = 456_u24;
    let c: u24 = 10_u24;

    println!("d = {}", a + b);
    println!("e = {}", a.wrapping_sub(b));
    println!("f = {}", u24::MAX - (c >> 1_u32));
  }
}

Use the exint::uint_strict! macro to avoid converting the core integer types.

use exint::uint;

fn main() {
  exint::uint! {
    let a: uint<3> = 123_u24;  // <-- Converted
    let b: uint<4> = 456_u32;  // <-- Converted
  }

  exint::uint_strict! {
    let a: uint<3> = 123_u24;  // <-- Converted
    let b: u32 = 456_u32;  // <-- Not converted
  }
}

Security

This crate is not intended for cryptographic use. Consider using crypto-bigint if you need an integer type suitable for cryptographic applications.

Features

License