derive/
derive.rs

1//! pretty basic derive example with external function
2
3use bpaf::{short, Bpaf, Parser};
4use std::path::PathBuf;
5
6#[derive(Debug, Clone, Bpaf)]
7#[bpaf(options, version)]
8#[allow(dead_code)]
9struct Opts {
10    /// Activate debug mode
11    #[bpaf(short, long)]
12    debug: bool,
13    /// this comment is ignored
14    #[bpaf(external(verbose))]
15    verbose: usize,
16    /// Set speed
17    #[bpaf(argument("SPEED"), fallback(42.0))]
18    speed: f64,
19    /// Output file
20    output: PathBuf,
21
22    #[bpaf(guard(positive, "must be positive"), fallback(1))]
23    nb_cars: u32,
24    files_to_process: Vec<PathBuf>,
25}
26
27fn verbose() -> impl Parser<usize> {
28    // number of occurrences of the v/verbose flag capped at 3
29    short('v')
30        .long("verbose")
31        .help("Increase the verbosity\nYou can specify it up to 3 times\neither as -v -v -v or as -vvv")
32        .req_flag(())
33        .many()
34        .map(|xs| xs.len())
35        .guard(|&x| x <= 3, "It doesn't get any more verbose than this")
36}
37
38fn positive(input: &u32) -> bool {
39    *input > 0
40}
41
42fn main() {
43    println!("{:#?}", opts().run());
44}
derive/derive.rs

derive/
derive.rs
