Honestly, it’s not much better than a complicated synchronous program.At this point, we should refactor our request out to a separate functionThat looks better. There’s no need to pull in Write in that template?
In your example your methods returns integer constant value which is no a IO operation.
} For example, consider code like this:As you can imagine, this can quickly lead to very complex code for larger projects. async_read_file( min_len { } Even though the implementation details of these nested futures are opaque to me as a programmer, they are known to the compiler, which lays them out optimally inside a single type.Fast forward a year or two, and more and more people are realizing that while combinator-based Futures are extremely powerful, they aren’t always that fun to write. You can use it with the active ecosystem of asynchronous I/O around futures, mio, tokio, and async-std. which basically does the same thing.This comes in handy when you want to run futures concurrently (i.e., tasks that are progressing simultaneously).This is a common problem when writing async code in general.
} If you want to check it out for yourself install `cargo install cargo-expand` and run `cargo expand` in the root of a project with the example code in `main.rs`.
Go 程序员都知道，Gin 是一个优秀的框架，性能也不错，最近有时间折腾 rust ，正好拿 rust 做个对比。从一个简单的程序开始：获取所有用户，即从数据库查询所有用户并以 json 格式返回，涉及到的 SQL 语句很 … }
The problem is, we’re allocating space for two iterators instead of one. The generated code for this could look like this:Note that this function does not start the execution of the state machine. I like to instantiate the runtime explicitly, which is what we’ll do in the template below.Most of my async application projects start with a Async functions in Rust differ somewhat from what you’re used to.
What we’re left with is a many-to-many relationship, like the following:The astute reader will note that this enum-like approach is exactly what we wanted earlier for our future type. 写文章. The keyboard interrupt is a good candidate for this because it is both non-deterministic and latency-critical. For example, if the In order to be able to continue from the last waiting state, the state machine must keep track of the current state internally. enable_interrupts_and_hlt(); This happens because impl Future is a concrete unique type while dyn Future is an abstract type.HashMap expects the abstract type since it can only hold instances of a single type.. } task_id); ExampleStateMachine::Start(StartState { Err(crossbeam_queue::PopError) .take(); ) -> impl Future