runa/runa-std/actors/counter.rn

pub fn handle(ctx, state, sender, message) {
    if message.op == "send" {
        ctx.send(message.target, #{op: "add", value: message.value});
        state + 1
    } else if message.op == "add" {
        state + message.value
    } else {
        panic("unknown counter operation")
    }
}