go-packages

Is there a way in Go to list all the standard/built-in packages (i.e., the packages which come installed with a GoLang installation)? I have a list of packages and I want to figure out which packages are standard. You can use the new golang.org/x/tools/go/packages for this. This provides a programmatic interface for most of go list : package main import ( "fmt" "golang.org/x/tools/go/packages" ) func main() { pkgs, err := packages.Load(nil, "std") if err != nil { panic(err) } fmt.Println(pkgs) // Output: [archive/tar archive/zip bufio bytes compress/bzip2 ... ] } To get a isStandardPackage()

I can not find a way to factor out some code from main.go into a local package when using Go modules (go version >= 1.11) outside of $GOPATH . I am not importing any external dependencies that need to be included into go.mod , I am just trying to organize locally the source code of this Go module. The file main.go : package main // this import does not work import "./stuff" func main() { stuff.PrintBaz() } The file ./stuff/bar.go (pretending to be a local package): package stuff import "log" type Bar struct { Baz int } func PrintBaz() { baz := Bar{42} log.Printf("Bar struct: %v", baz) } The