Macro negative_i32 

macro_rules! negative_i32 {
    ($e:expr $(,)?) => { ... };
}

Creates a NegativeI32 checked at compile time.

This macro takes a single argument that must be a negative i32. Positive values will cause a compile error.

use sign_bound::{NegativeI32, negative_i32};

let val: NegativeI32 = negative_i32!(-123);