The Go runtime and standard libraries do not provide goroutine local storage or a goroutine identifier that can be used to implement goroutine local storage. The third party gls package implements goroutine local storage in an interesting way. Some find this package horrifying and others think it’s clever. The Go team recommends passing context explicitly … Read more
Go uses case to determine whether a particular identifier is public or private within the context of your package. In your first example, the fields are not visible to json.Marshal because it is not part of the package containing your code. When you changed the fields to be upper case, they became public so could … Read more
What you are doing is a fan out pattern, that is to say, multiple endpoints are listening to a single input source. The result of this pattern is, only one of these listeners will be able to get the message whenever there’s a message in the input source. The only exception is a close of … Read more
The simplest way, I suppose, is to create 250 goroutines and pass them a channel which you can use to pass links from main goroutine to child ones, listening that channel. When all links are passed to goroutines, you close a channel and all goroutines just finish their jobs. To secure yourself from main goroutine … Read more
No it’s not safe even though you may not sometimes observe any troubles. IIRC, the fmt package tries to be on the safe side, so probably intermixing of some sort may occur but no process crash, hopefully. This is an instance of a more universal Go documentation rule: Things are not safe for concurrent access … Read more
The rule is simple: if multiple goroutines access a variable concurrently, and at least one of the accesses is a write, then synchronization is required. Your example does not violate this rule. You don’t write the slice value (the slice header), you only read it (implicitly, when you index it). You don’t read the slice … Read more
Using Error Group makes this even simpler. This automatically waits for all the supplied Go Routines to complete successfully, or cancels all those remaining in the case of any one routine returning an error (in which case that error is the one bubble back up to the caller). package main import ( “context” “fmt” “math/rand” … Read more
There is nothing wrong with guarding the MySlice = append(MySlice, &OneOfMyStructs) with a sync.Mutex. But of course you can have a result channel with buffer size len(params) all goroutines send their answers and once your work is finished you collect from this result channel. If your params has a fixed size: MySlice = make([]*MyStruct, len(params)) … Read more
Coroutines in Kotlin are implemented in a different way than goroutines in Go, so which one is “faster” depends on the problem that you are solving and the kind of code you are writing. In general, it is very hard to tell in advance which one is going to work better for a problem you … Read more
This famous quote can be a little bit confusing if taken too litterally. Let’s break it down to its more basic components, and define them properly: Don’t communicate by sharing memory; share memory by communicating —- 1 —- —— 2 —– —- 3 —– —– 4 —– This means that different threads of execution would … Read more