Let's start with some basics (and maybe obvious) things.
First, a little recap; a slice is a constant view over an array, and &[T] is the constant view of a Vec<T>, whereas &str is the constant view of a String (just like Path is the constant view of a PathBuf and OsStr is the constant view of an OsString). Now that you have this in mind, let's continue!
When a function expects a constant argument of type Vec or String, then always write them as follows:
fn some_func(v: &[u8]) {
// some code...
}Instead of:
fn some_code(v: &Vec<u8>) {
// some code
}And:
fn some_func(s: &str) {
// some code...
}Instead of:
fn some_func(s: &String) {
// some code...
}You might be wondering why this is the case. So, let's imagine your function displays your Vec as ASCII characters:
fn print_as_ascii(v: &[u8]) {
for c in v {
print!("{}", *c as char);
}
println!("");
}And now you just want to print a part of your Vec...