It's interesting to take note of the actual Rust `File` object: https://doc.rust-lang.org/std/fs/struct.File.html https://doc.rust-lang.org/std/fs/struct.File.h

It's interesting to take note of the actual Rust `File` object: https://doc.rust-lang.org/std/fs/struct.File.html https://doc.rust-lang.org/std/fs/struct.File.html `open` is a static function on the `File` object and an instance of `File` does not have a `close` method at all. So, as in this article, an instance of `File` can only be created if `open` succeeded and the file will be closed when dropped (either implicitly or explicitly). For example: fn main() -> std::io::Result<()> { // a file object is only created if File::create is successful // otherwise main returns an error let mut file = File::create("foo.txt")?; file.write_all(b"Hello, world!")?; Ok(()) } // file closed here, no close method needed. This contrasts with many other languages where a class instance can be in an invalid state. This is something the typestate pattern helps to avoid.