For a fixed-size struct, is it possible to read or write in a single operation?

I wrote a demo using binrw, and upon observing the read and write process, I found that for fixed-size structs, binrw always reads or writes the struct members one by one. This seems quite odd. In the case of a large number of structs, frequent reads or writes could impact performance.

Here is the demo code:

rust
#[binrw]
pub struct A {
a: u32,
b: [u8; 10],
}
This block of code should be able to be read or written in one go, but when I use a NoSeek-wrapped reader or writer to read or write, I observed that it first reads or writes the a in A, and then reads or writes the b in A.

Start by reproducing the demo with struct A and a NoSeek-wrapped reader or writer, then inspect how binrw processes each field. Done means establishing whether a fixed-size struct can be read or written in one operation and verifying the resulting behavior against the reported performance concern.

Written by the indexing model from the issue text.