restrictions for an option

[kindlychung]

For example, I have a "--filetype" option and only asciidoc or markdown are allowed. Is there a way to do this? Of course a match {} block can be used, but is there is mechanism in the library to automate this?

[BurntSushi]

You might try decoding into an enum with only those two options.

[kindlychung]

Cool. Thanks!