mirror of
https://github.com/clap-rs/clap
synced 2024-12-14 14:52:33 +00:00
feat(parser): Check if args were present
In clap2, `ArgMatches.args` was public but hidden. We made it private in clap3, giving us more implementation flexibility but many people relied on it, like to short-circuit defaulting, providing their own `ArgRequiredElseHelp`, etc. The main problem was how to expose this - If we think of `ArgMatches` as a container (a DAG), should we have an `is_empty` and what all is included in that, like subcommands? - If we focus on only args, what term how do we refer to this to convey the right intent? In the end, I realized that this aligns most with our existing `is_present` check and reporting if args are present fits the best within the existing API. I looked into also exposing iterating over the args (`present_arg_ids`) but we have no way to expose the Id. The Id is currently private and if we made it public, it can't be used to access any arg because it can't implement `Key`. This supersedes #3265
This commit is contained in:
parent
8efee8a671
commit
50a58e98eb
1 changed files with 23 additions and 0 deletions
|
@ -80,6 +80,29 @@ pub struct ArgMatches {
|
|||
}
|
||||
|
||||
impl ArgMatches {
|
||||
/// Check if any args were present on the command line
|
||||
///
|
||||
/// # Examples
|
||||
///
|
||||
/// ```rust
|
||||
/// # use clap::{App, Arg};
|
||||
/// let mut app = App::new("myapp")
|
||||
/// .arg(Arg::new("output")
|
||||
/// .takes_value(true));
|
||||
///
|
||||
/// let m = app
|
||||
/// .try_get_matches_from_mut(vec!["myapp", "something"])
|
||||
/// .unwrap();
|
||||
/// assert!(m.args_present());
|
||||
///
|
||||
/// let m = app
|
||||
/// .try_get_matches_from_mut(vec!["myapp"])
|
||||
/// .unwrap();
|
||||
/// assert!(! m.args_present());
|
||||
pub fn args_present(&self) -> bool {
|
||||
!self.args.is_empty()
|
||||
}
|
||||
|
||||
/// Gets the value of a specific option or positional argument.
|
||||
///
|
||||
/// i.e. an argument that [takes an additional value][crate::Arg::takes_value] at runtime.
|
||||
|
|
Loading…
Reference in a new issue