Go中的通道，node.js中的发射器？

Does Go have an equivalent of node.js' "emitter"?

I'm teaching myself Go by porting over a node.js library I wrote. In the node version, the library emits an event once something happens (e.g. it listens on UDP port 1234 and when "ABC" is received, "abcreceived" is emitted so the calling code can respond as necessary (e.g. sending back "DEF")

I've seen channels in Go (and am currently reading up on them), but as I'm still new to this language, I don't know if (or how, for that matter) that can be used to communicate with whatever code is using my library.

I've also seen https://github.com/chuckpreslar/emission, but am not sure if this is acceptable, or if there's a better ("Best practice") way of doing things.

So by reading others' Go code and some links in the comments to my question, I think channels are the way to go.

In my library code (semi pseudo-code):

// Make a new channel called "Events"
var Events = make(chan 

func doSomething() {
    // ...
    Events <-"abcreceived" // Add "abcreceived" to the Events channel
}

And in the code that will use my library:

evt := <-mylib.Events

switch evt {
    case "abcreceived":
        sendBackDEF()
        break
    // ...
}

I still prefer node.js' EventEmitter (because you can transfer data back easily) but for simple things, this should suffice.

Go and Node.js are very different. Node.js supports concurrency only via callbacks. There might be various ways of dressing them up, but they're fundamentally callbacks.

In Node.js, there is no parallelism; Node.js has a single-threaded runtime. When Node.js async is used to achieve what is called 'parallel' execution, it isn't parallel in the sense used in Go, but concurrent.

Concurrency is not parallelism in the Go world.

Go has explicit concurrency based on Communicating Sequential Processes (CSP), a mathematical basis conceived by Tony Hoare at Oxford. The runtime interleaves cooperating processes called goroutines by time-slicing them onto the available CPU cores. Within each goroutine, the code is single threaded, so is easy to write. In the simple case, no data is shared between goroutines; instead messages pass between them along channels. In this way, there is no need for callbacks.

When goroutines get blocked waiting for I/O, that's OK because they don't use any CPU time until they're unblocked. Their memory footprint is slight and you can have very large numbers of them. So callbacks are not needed for I/O operations either.

Because the execution models of Go and Node.js are about as different as they could be, attempting to port code from one to the other is very likely to lead to very clumsy solutions. It's better to start from the original requirements and implement from scratch.

It would be possible to distort the Go concurrency model using function arguments to behave like callbacks. This would be a bad idea because it would not be idiomatic and would lose the benefits that CSP gives.