package main import ( "fmt" "launchpad.net/gnuflag" ) func main() { var name string fs := gnuflag.NewFlagSet("myflags", gnuflag.ExitOnError) fs.StringVar(&name, "name", "World", "A greeting message") fs.Parse(true) fmt.Printf("Hello, %s!\n", name) }In this example, we create a new FlagSet and add a string flag called "name". We also use the StringVar method to set a default value of "World" and provide a description of the flag. The Parse method is called to parse the command-line arguments and retrieve the value of the "name" flag. Finally, we print out a greeting message using the value of the "name" flag. This example shows how launchpad.net.gnuflag package library can be used to define and parse command-line arguments.