Go Modules

x.go

Hell
├── main.go 
└── world
    └── test.go
------------------------------------------|------------------------------------------
main.go:                                  |test.go:
    package main                          |  package world
    import "example.com/modulename/world" |  import "fmt"
    func main(){world.Quest()}            |   func Quest(){fmt.Println("test done!")}
------------------------------------------|------------------------------------------

1. run "go mod init example.com/modulename
2. Import with main.go -> import "example.com/modulename/world"
3. Call the function "Quest" with main.go -> "world.Quest()"
[IMPORTANT: Your function has to start with a capilat letter because god knows why] <- https://golang.org/ref/spec#Exported_identifiers
5. Profit

Reference: https://blog.golang.org/using-go-modules