mirror of
https://github.com/clap-rs/clap
synced 2024-12-13 14:22:34 +00:00
38 lines
955 B
Rust
38 lines
955 B
Rust
// Note: this requires the `cargo` feature
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use std::ops::RangeInclusive;
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use clap::{arg, command};
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fn main() {
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let matches = command!()
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.arg(
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arg!(<PORT>)
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.help("Network port to use")
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.validator(port_in_range),
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)
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.get_matches();
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// Note, it's safe to call unwrap() because the arg is required
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let port: usize = matches
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.value_of_t("PORT")
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.expect("'PORT' is required and parsing will fail if its missing");
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println!("PORT = {}", port);
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}
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const PORT_RANGE: RangeInclusive<usize> = 1..=65535;
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fn port_in_range(s: &str) -> Result<(), String> {
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let port: usize = s
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.parse()
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.map_err(|_| format!("`{}` isn't a port number", s))?;
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if PORT_RANGE.contains(&port) {
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Ok(())
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} else {
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Err(format!(
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"Port not in range {}-{}",
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PORT_RANGE.start(),
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PORT_RANGE.end()
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))
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}
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}
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