proxy.sw

contract;

abi ProxyAbi {
    #[storage(read)]
    fn read_val() -> u64;
    #[storage(write)]
    fn write_target(target: ContractId);
}

#[namespace(proxy_47892374)]
storage {
    target: ContractId,
}

impl ProxyAbi for Contract {
    #[storage(read)]
    fn read_val() -> u64 {
        let target = storage.target.read();
        std::execution::run_external(target);
    }
    #[storage(write)]
    fn write_target(target: ContractId) {
        storage.target.write(target);
    }
}

target.sw

contract;

abi TargetAbi {
    #[storage(read)]
    fn read_val() -> u64;
    #[storage(write)]
    fn write_val(val: u64);
}

storage {
    val: u64,
}

impl TargetAbi for Contract {
    #[storage(read)]
    fn read_val() -> u64 {
        storage.val.read()
    }
    #[storage(write)]
    fn write_val(val: u64) {
        storage.val.write(val);
    }
}