Apply Method

Overview

Allows you to apply any function given as a parameter to the object.

As you are able to connect operations to the object with chains, it allow you to describe the sequence of operations neatly. This is useful, for example, if you want to change the internal state with other method after the object is created.

Examples

#[derive(Debug, PartialEq)]
struct Dog {
    name: String,
    size: String,
}
impl Dog {
    fn new() -> Self {
        Self {
            name: "Pochi".to_string(),
            size: "Middle".to_string(),
        }
    }
}
let mut exact_dog = Dog::new();
exact_dog.size = "Big".to_string();
let dog = Dog::new().apply(|it| it.size = "Big".to_string());
assert_eq!(dog, exact_dog);

let mut exact_path = PathBuf::from(env!("CARGO_MANIFEST_DIR"));
exact_path.push("src/lib.rs");
let path = PathBuf::from(env!("CARGO_MANIFEST_DIR")).apply(|it| it.push("src/lib.rs"));
assert_eq!(path, exact_path);

let mut exact_path = PathBuf::from(env!("CARGO_MANIFEST_DIR"));
exact_path.push("src/lib.rs");
let path = PathBuf::from(env!("CARGO_MANIFEST_DIR"))
    .apply(|it| it.push("src"))
    .apply(|it| it.push("lib.rs"));
assert_eq!(path, exact_path);

let mut exact_path = PathBuf::from(env!("CARGO_MANIFEST_DIR"));
exact_path.push("src/lib.rs");
let path =
    PathBuf::from(env!("CARGO_MANIFEST_DIR")).apply_with_param(PathBuf::push, "src/lib.rs");
assert_eq!(path, exact_path);

let mut exact_path = PathBuf::from(env!("CARGO_MANIFEST_DIR"));
exact_path.push("src");
exact_path.push("lib.rs");
let path = PathBuf::from(env!("CARGO_MANIFEST_DIR"))
    .apply_with_params(PathBuf::push, vec!["src", "lib.rs"]);
assert_eq!(path, exact_path);