__anonymousmixin DEF!("greet", string, Flag_d!"-g [greeting]", Desc_d!"set the greeting string", Default_d!"hi!", Preset_d!"hello!", Negate_d!("-G", "opposite to `--greet`"), Export_d!("-x", "-y", "-z", "--xyz"), N_Export_d!("-X", "-Y", "-Z", "--XYZ"))