Function embassy_futures::block_on

pub fn block_on<F: Future>(fut: F) -> F::Output

以忙循环（busy loop）的方式运行一个future直到其完成
Run a future to completion using a busy loop.

block_on函数接收一个实现了Future trait的参数fut， 然后在一个忙循环中调用.poll()方法，这会阻塞当前线程并占用100%的CPU，直到Future完成。 future中的Waker机制没有被使用。

您可以使用这个来并发地运行多个future，例如join。

这适合于没有或只有有限并发需求的系统，对功耗没有严格要求。 对于更复杂的用例，更推荐使用像embassy-executor这样的“真正“的执行器， 它支持多任务，并在没有任务需要工作时让核心进入睡眠状态。

---

Run a future to completion using a busy loop.

This calls .poll() on the future in a busy loop, which blocks the current thread at 100% cpu usage until the future is done. The future’s Waker mechanism is not used.

You can use this to run multiple futures concurrently with join.

It’s suitable for systems with no or limited concurrency and without strict requirements around power consumption. For more complex use cases, prefer using a “real” executor like embassy-executor, which supports multiple tasks, and putting the core to sleep when no task needs to do work.