Set

The Set derive macro generates setter methods for struct fields. Annotate fields with #[moxy(set)] to opt in — unannotated fields get no setter.

Setters use Into<T> for flexible type coercion (consistent with Build) and return &mut Self for chaining.

Note

Set setters return &mut Self and borrow mutably — they do not consume self. This is different from Build setters, which consume the builder to advance the typestate.

Basic Usage

use moxy::Set;

#[derive(Set)]
struct Config {
    #[moxy(set)]
    host: String,
    #[moxy(set)]
    port: u16,
    read_only: bool,
}

let mut cfg = Config { host: String::new(), port: 0, read_only: true };

// &str → String via Into, chaining via &mut Self
cfg.set_host("localhost").set_port(8080_u16);

assert_eq!(cfg.host, "localhost");
assert_eq!(cfg.port, 8080);
// cfg.set_read_only() — no annotation, no setter

What’s Next

• Option Fields — automatic Some wrapping for Option<T> fields
• Callbacks — transforms and side effects with on = expr