# Crates

The `crate_type` attribute can be used to tell the compiler whether a crate is
a binary or a library (and even which type of library), and the `crate_name`
attribute can be used to set the name of the crate.

However, it is important to note that both the `crate_type` and `crate_name`
attributes have **no** effect whatsoever when using Cargo, the Rust package
manager. Since Cargo is used for the majority of Rust projects, this means
real-world uses of `crate_type` and `crate_name` are relatively limited.

```rust,editable
// This crate is a library
#![crate_type = "lib"]
// The library is named "rary"
#![crate_name = "rary"]

pub fn public_function() {
    println!("called rary's `public_function()`");
}

fn private_function() {
    println!("called rary's `private_function()`");
}

pub fn indirect_access() {
    print!("called rary's `indirect_access()`, that\n> ");

    private_function();
}
```

When the `crate_type` attribute is used, we no longer need to pass the
`--crate-type` flag to `rustc`.

```bash
$ rustc lib.rs
$ ls lib*
library.rlib
```
