options

spec, err := Parse(`
    usage: example-tool
    A short description of the command
    --
    flag        --flag,-f,FLAG           A description for this flag
    option=     --option=,-o=,OPTION=    A description for this option
                                         the description continues here
    !required=  --required,-r=,REQUIRED= A required option
    --
    env_var=    ENV_VAR=                 An environment variable
    --
    help        help,h                   Show this help message
    run         run                      Run some function
    --
    More freestyle text
    `)
if err != nil {
	spec.PrintUsageWithError(err)
}

opts, err := spec.Interpret([]string{"example-tool", "--required", "hello world"}, []string{})
if err != nil {
	spec.PrintUsageWithError(err)
}

fmt.Printf("required: %s", opts.Get("required"))

Output:

required: hello world