Default Argument Value
To demonstrate usage of default values of arguments.
Setup
parser := argparse.NewParser("default", "Program to test default values")
Required is false
Create an argument where the required option is set to false:
s := parser.String("s", "string", &argparse.Options{Required: false, Help: "String to print", Default: "Hello"})
On execution of program, which prints the argument as
fmt.Println(*s)
$ go run default.go
Hello
Also, the default value is printed in the help.
Required is true
s := parser.String("s", "string", &argparse.Options{Required: true, Help: "String to print", Default: "Hello"})
On execution,
$ go run default.go
[-s|--string] is required
usage: default [-h|--help] -s|--string "<value>"
Program to test default values
Arguments:
-h --help Print help information
-s --string String to print
exit status 1