Attribute Macro lockjaw::module_attributes::into_vec

#[into_vec]

Denotes the return value of the binding should be collected into a Vec<T>.

Vec<T> can then be depended on to access all bindings of T.

A module provide the binding to the Vec<T> at most once. However if 2 different module provides a binding with the same value it will not be deduplicated.

The counterpart of #[into_vec] in Dagger is @IntoSet. Since eq/hash is less universally available in Rust Vec<T> is the chosen collection.

If a #[into_vec] binding is also #[qualified(Q)], the result is collected into #[qualified(Q)] Vec<T>.

struct MyModule;

#[module]
impl MyModule {

    #[provides]
    #[into_vec]
    pub fn provide_string1() -> String {
        "string1".to_owned()
    }

    #[provides]
    #[into_vec]
    pub fn provide_string2() -> String {
        "string2".to_owned()
    }
}

#[component(modules: MyModule)]
pub trait MyComponent {
    fn vec_string(&self) -> Vec<String>;
}

pub fn main() {
    let component: Box<dyn MyComponent> = <dyn MyComponent>::new();
    let v = component.vec_string();
    assert!(v.contains(&"string1".to_owned()));
    assert!(v.contains(&"string2".to_owned()));
}

epilogue!();