Trait implementations

The impl A for B is supported, and is translated to a class B implements A. In addition, the methods inside this impl block will also be converted automatically.

Unignore a function

Some trait implementations are ignored by default to avoid generating meaningless things to Dart side such as clone and deref. However, if a function is ignored while you want it, you can put arbitrary attributes on it to tell flutter_rust_bridge you want it. For example, #[frb] fn f() { .. } suffices. Attributes with real contents like #[frb(sync)] fn f() { .. } also works.

Example

For example, suppose we write down:

impl MyTrait for MyStruct {
    fn f(&self, a: String) -> i32 { ... }
}

Then, the generated MyStruct class will be like:

class MyStruct implements MyTrait {
    ...
    int f(String a) => ...;
}

Therefore, the trait can act as an "interface" or an "abstract class" in the Dart world.