Rust Auto-dereferencing Using Deref and AsRef for function arguments
Example
For functions that need to take a collection of objects, slices are usually a good choice:
fn work_on_bytes(slice: &[u8]) {}
Because Vec<T> and arrays [T; N] implement Deref<Target=[T]>, they can be easily coerced to a slice:
let vec = Vec::new();
work_on_bytes(&vec);
let arr = [0; 10];
work_on_bytes(&arr);
let slice = &[1,2,3];
work_on_bytes(slice); // Note lack of &, since it doesn't need coercing
However, instead of explicitly requiring a slice, the function can be made to accept any type that can be used as a slice:
fn work_on_bytes<T: AsRef<[u8]>>(input: T) {
let slice = input.as_ref();
}
In this example the function work_on_bytes will take any type T that implements as_ref(), which returns a reference to [u8].
work_on_bytes(vec);
work_on_bytes(arr);
work_on_bytes(slice);
work_on_bytes("strings work too!");
