```rust use bytecheck::{CheckBytes, check_bytes, rancor::Failure}; #[derive(CheckBytes, Debug)] #[repr(C)] struct Test { a: u32, b: char, c: bool, } #[repr(C, align(4))] struct Aligned([u8; N]); macro_rules! bytes { ($($byte:literal,)*) => { (&Aligned([$($byte,)*]).0 as &[u8]).as_ptr() }; ($($byte:literal),*) => { bytes!($($byte,)*) }; } // In this example, the architecture is assumed to be little-endian #[cfg(target_endian = "little")] unsafe { // These are valid bytes for a `Test` check_bytes::( bytes![ 0u8, 0u8, 0u8, 0u8, 0x78u8, 0u8, 0u8, 0u8, 1u8, 255u8, 255u8, 255u8, ].cast() ).unwrap(); // Changing the bytes for the u32 is OK, any bytes are a valid u32 check_bytes::( bytes![ 42u8, 16u8, 20u8, 3u8, 0x78u8, 0u8, 0u8, 0u8, 1u8, 255u8, 255u8, 255u8, ].cast() ).unwrap(); // Characters outside the valid ranges are invalid check_bytes::( bytes![ 0u8, 0u8, 0u8, 0u8, 0x00u8, 0xd8u8, 0u8, 0u8, 1u8, 255u8, 255u8, 255u8, ].cast() ).unwrap_err(); check_bytes::( bytes![ 0u8, 0u8, 0u8, 0u8, 0x00u8, 0x00u8, 0x11u8, 0u8, 1u8, 255u8, 255u8, 255u8, ].cast() ).unwrap_err(); // 0 is a valid boolean value (false) but 2 is not check_bytes::( bytes![ 0u8, 0u8, 0u8, 0u8, 0x78u8, 0u8, 0u8, 0u8, 0u8, 255u8, 255u8, 255u8, ].cast() ).unwrap(); check_bytes::( bytes![ 0u8, 0u8, 0u8, 0u8, 0x78u8, 0u8, 0u8, 0u8, 2u8, 255u8, 255u8, 255u8, ].cast() ).unwrap_err(); } ```