diff options
Diffstat (limited to 'vendor/clap/examples/tutorial_builder/04_02_validate.rs')
-rw-r--r-- | vendor/clap/examples/tutorial_builder/04_02_validate.rs | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/vendor/clap/examples/tutorial_builder/04_02_validate.rs b/vendor/clap/examples/tutorial_builder/04_02_validate.rs new file mode 100644 index 000000000..e60018a46 --- /dev/null +++ b/vendor/clap/examples/tutorial_builder/04_02_validate.rs @@ -0,0 +1,38 @@ +// Note: this requires the `cargo` feature + +use std::ops::RangeInclusive; + +use clap::{arg, command}; + +fn main() { + let matches = command!() + .arg( + arg!(<PORT>) + .help("Network port to use") + .value_parser(port_in_range), + ) + .get_matches(); + + // Note, it's safe to call unwrap() because the arg is required + let port: u16 = *matches + .get_one::<u16>("PORT") + .expect("'PORT' is required and parsing will fail if its missing"); + println!("PORT = {}", port); +} + +const PORT_RANGE: RangeInclusive<usize> = 1..=65535; + +fn port_in_range(s: &str) -> Result<u16, String> { + let port: usize = s + .parse() + .map_err(|_| format!("`{}` isn't a port number", s))?; + if PORT_RANGE.contains(&port) { + Ok(port as u16) + } else { + Err(format!( + "Port not in range {}-{}", + PORT_RANGE.start(), + PORT_RANGE.end() + )) + } +} |