Compile-time checked non-zero integers with type inference and first-class const support.

const UNSIGNED: NonZeroUsize = nonzero!(1);
const SIGNED: NonZeroI8 = nonzero!(-1);
           // ^ correctly infers return type

const MY_CONST: usize = 20;
const MY_NONZERO_CONST: NonZeroUsize = nonzero!(MY_CONST - 19);
              // refer to other constant values ^

let runtime = nonzero!(0); // eager evaluation

Comparison with other libraries

• nonzero uses a proc-macro that parses the expression passed to it, precluding
  • Type inference.
  • Referencing constants.