Choices for ArgParse.jl argument

Question

In Python one can set the choices for a flag with argparse:

parser.add_argument('-q', 
                    dest='quality_scale', 
                    type=str, 
                    choices=["sanger", "illumina"],
                    help='Base quality scale',
                    required=True)

Is there a way to do this in Julia using ArgParse? I checked the documentation here (General settings), but I could not find anything.

Answer 1

You can use the range_tester parameter, which takes a one-argument function, to perform validation on the input value. Something like the following, which will only accept "a", "b", or "c".

s = ArgParseSettings()
@add_arg_table s begin
    "--opt"
        range_tester = in(["a", "b", "c"])
end