// Write an attribute macro that replaces the struct in its input with a byte // array representation of the correct size. For example the invocation in the // test case below might expand to the following where the `size` expression is // computed by summing the Specifier::BITS constant of each field type. // // #[repr(C)] // pub struct MyFourBytes { // data: [u8; #size], // } // // Don't worry for now what happens if the total bit size is not a multiple of // 8 bits. We will come back to that later to make it a compile-time error. use scryer_modular_bitfield::prelude::*; #[bitfield] pub struct MyFourBytes { a: B1, b: B3, c: B4, d: B24, } fn main() { assert_eq!(std::mem::size_of::(), 4); }