Access Control

Visibility/access scopes in Rust can be granular, but often you only need to know about pub(crate) and pub.

If the library has relatively few developers or is relatively small, encapsulation should be considered at the crate boundary versus individual modules within the crate.

pub(crate)

Use pub(crate) for access level control when you need to access something outside of its module. It allows you to access the type/field/function/item throughout the crate without making it available to any code outside the crate.

pub(crate) mod people {
  pub(crate) struct Person {
    pub(crate) name: String,
  }

  pub(crate) fn announce(p: Person) {
    // ...
  }
}

mod organization {
  struct Org {
    people: Vec<crate::people::Person>,
  }
}

If there are no invariants that need to be kept between the fields, then it is often unnecessary to generate getters/setters.

pub

If you are building a library, be judicious with pub.

Do not make individual fields of a struct/enum pub.