gust-stdlib 0.2.0

Standard library of reusable Gust state machines (circuit breaker, retry, saga, rate limiter, and more)
Documentation 
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machine RequestResponse<T, R> {
    state Pending(request: T, timeout_ms: i64)
    state Completed(response: R)
    state Failed(error: String)
    state TimedOut(elapsed_ms: i64)

    transition send: Pending -> Pending
    transition receive: Pending -> Completed | Failed
    transition timeout: Pending -> TimedOut

    async effect wait_for_response(request: T, timeout_ms: i64) -> Result<R, String>
    effect current_time_ms() -> i64

    on send() {
        goto Pending(request, timeout_ms);
    }

    async on receive() {
        let result = perform wait_for_response(request, timeout_ms);
        match result {
            Ok(response) => {
                goto Completed(response);
            }
            Err(err) => {
                goto Failed(err);
            }
        }
    }

    on timeout() {
        let elapsed = perform current_time_ms();
        goto TimedOut(elapsed);
    }
}