// For getters and setters, we would like for the signature to be in terms of // the narrowest unsigned integer type that can hold the right number of bits. // That means the accessors for B1 through B8 would use u8, B9 through B16 would // use u16 etc. use scryer_modular_bitfield::prelude::*; use std::mem::size_of_val; type A = B1; type B = B3; type C = B4; type D = B24; #[bitfield] pub struct MyFourBytes { a: A, b: B, c: C, d: D, } fn main() { let mut x = MyFourBytes::new(); // I am testing the signatures in this roundabout way to avoid making it // possible to pass this test with a generic signature that is inconvenient // for callers, such as `fn a>(&self) -> T`. let a = 1; x.set_a(a); // expect fn(&mut MyFourBytes, u8) let b = 1; x.set_b(b); let c = 1; x.set_c(c); let d = 1; x.set_d(d); // expect fn(&mut MyFourBytes, u32) assert_eq!(size_of_val(&a), 1); assert_eq!(size_of_val(&b), 1); assert_eq!(size_of_val(&c), 1); assert_eq!(size_of_val(&d), 4); assert_eq!(size_of_val(&x.a()), 1); // expect fn(&MyFourBytes) -> u8 assert_eq!(size_of_val(&x.b()), 1); assert_eq!(size_of_val(&x.c()), 1); assert_eq!(size_of_val(&x.d()), 4); // expect fn(&MyFourBytes) -> u32 }