async-methods.md

Async methods

Classes and structs may declare static and instance async methods. They use the same one-shot task<T>, spawn, and await model as namespace functions:

class Worker {
    int32 base;

    public Worker(int32 value) {
        base = value;
    }

    public async const int32 calculate(int32 extra) {
        return base + extra;
    }
}

async int32 main() {
    const Worker* worker = new Worker(40);
    task<int32> result = spawn worker.calculate(2);
    return await result;
}

Static async methods need no receiver. An instance async method must be const and its spawn receiver must be a named const value or managed owner. Raw pointers, managed subscribers, temporaries, mutable bindings, and receiver types that own managed pointers, arrays, or other resources are rejected at compile time. These restrictions keep the captured this address valid until the mandatory await without introducing a new runtime pointer kind.

Virtual class methods retain normal virtual dispatch: the task thunk resolves the vtable slot after decoding the receiver. Struct methods use their direct method ABI. Scalar/enum argument and result restrictions remain unchanged.

@task(core, priority, role) works on async methods, and a spawn-site @spawn(...) may override those defaults for one method launch. An override must preserve the inherited method's async contract.