Positional arguments in reverse order

[b1rger]

Hi,

I am trying to mimic the behavior of the cal tool using clap. In cal there are 0 to 3 positional arguments: year, month and day. The problem is that they are given in the reverse order:

• One argument denotes the year
• Two arguments are: <month> <year>
• Three arguments are: <day> <month> <year>

Is it possible to implement something like this using clap? I know I could simple have posarg1, posarg2 and posarg3 and then add custom logic to do assignment, validation, help and so on, but I was wondering if it was possible to use the clap onboard features.

[pksunkara]

I don't remember any specific feature for this in clap. We don't allow optional positional arguments to appear before required positional ones.

I am afraid that you have to do what you are suggesting instead.