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#[derive(Debug)]
struct File {
name: String,
data: Vec<u8>,
}
impl File {
fn new(name: &str) -> File { // <1> As `File::new()` is a completely normal function--rather than something blessed by the language--we need to tell Rust that it will be returning a `File` from this function
File { // <2>
name: String::from(name), // <2> `File::new()` does little more than encapsulate the object creation syntax
data: Vec::new(), // <2>
}
}
// fn len(&self) -> usize { // <3> `File::len()` takes an implicit argument `self`. You'll notice that there is no explicit argument provided on line 25.
// self.data.len() // <4> `usize` is the type returned by `Vec<T>::len()`, which is sent directly through to the caller
// }
}
fn main() {
let f3 = File::new("f3.txt");
let f3_name = &f3.name; // <5> Fields are private by default, but can be accessed within the module that defines the struct. The module system is discussed further on in the chapter.
//let f3_length = f3.len();
let f3_length = f3.data.len();
println!("{:?}", f3);
println!("{} is {} bytes long", f3_name, f3_length);
}
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