Validate all arguments together

[epage]

Issue by giggio
Saturday Feb 06, 2021 at 22:12 GMT
Originally opened as clap-rs/clap#2332

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Describe your use case

I'd like to have a validation function that would validate the arguments together.

Describe the solution you'd like

I'm thinking something like this:

App::new("x")
    .validate(|args| /* some logic and... */ Err(("myarg", "Why invalid"));

(I'm not married to this example, it is just so we can have an idea)

In this case, argument myarg is invalid, after I've gone through some logic that would go through all arguments already supplied (and validated individually).

Alternatives, if applicable

Validate after parsing using ArgMatches.

Additional context

Already discussed at #1913 and #1206, and I think a solution with a closure after on the app context could make sense.