Yes, it’s possible. The trick is to start from a pointer to the type (whose value can be a typed nil, that’s perfectly OK), and then use Type.Elem() to get the reflect.Type descriptor of the pointed type (the base type). See some examples: t := reflect.TypeOf((*int)(nil)).Elem() fmt.Println(t) t = reflect.TypeOf((*http.Request)(nil)).Elem() fmt.Println(t) t = reflect.TypeOf((*os.File)(nil)).Elem() fmt.Println(t) … Read more
In Go, arrays are inflexible (because their length is encoded in their type) and costly to pass to functions (because a function operates on copies of its array arguments). I’m assuming you’d like to operate on slices rather than on arrays. Because methods cannot take additional type arguments, you cannot simply declare a generic Map … Read more
time.Time is a struct. When you try to compare them with ==, quoting from the Spec: Comparison operator: Struct values are comparable if all their fields are comparable. Two struct values are equal if their corresponding non-blank fields are equal. So t1 == t2 will compare all the fields of the 2 Time struct values. … Read more
In a Makefile recipe section you will need to escape the $ using a second $: test: go test $$(go list ./… | grep -v /vendor/) .PHONY: test
When you call a function or a method and you pass parameters to it, a copy is made from the values, and the function can only access these copies. This means if the function attempts to modify / change the copies, it will not change the original value. For example: func main() { i := … Read more
This is normal behaviour that is defined by the spec (emphasis mine): The TypeSwitchGuard may include a short variable declaration. When that form is used, the variable is declared at the beginning of the implicit block in each clause. In clauses with a case listing exactly one type, the variable has that type; otherwise, the … Read more
Introduction In Go the net/http package is used to provide Web Server functionality. This is not a static fileserver, it is much more than that. There is no filesystem “root” concept. The provided web server uses handlers to serve HTTP requests which are mapped to URLs. A handler is responsible to process an HTTP request … Read more
The slice header is represented by the reflect.SliceHeader type: type SliceHeader struct { Data uintptr Len int Cap int } You may use package unsafe to convert a slice pointer to *reflect.SliceHeader like this: sh := (*reflect.SliceHeader)(unsafe.Pointer(&newSlice2)) And then you may print it like any other structs: fmt.Printf(“%+v”, sh) Output will be (try it on … Read more
Passing everything to bash works, but here’s a more idiomatic way of doing it. package main import ( “fmt” “os/exec” ) func main() { grep := exec.Command(“grep”, “redis”) ps := exec.Command(“ps”, “cax”) // Get ps’s stdout and attach it to grep’s stdin. pipe, _ := ps.StdoutPipe() defer pipe.Close() grep.Stdin = pipe // Run ps first. … Read more
The code you posted works (with a reasonable command executed). Here is a simple “some long running task” written in Go for you to call and test your code: func main() { fmt.Println(“Child started.”) time.Sleep(time.Second*2) fmt.Println(“Tick…”) time.Sleep(time.Second*2) fmt.Println(“Child ended.”) } Compile it and call it as your command. You will see the different lines appear … Read more