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use std::path::PathBuf;
fn parse_dashnum(parser: &mut lexopt::Parser) -> Option<u64> {
let mut raw = parser.try_raw_args()?;
let arg = raw.peek()?.to_str()?;
let num = arg.strip_prefix('-')?.parse::<u64>().ok()?;
raw.next(); Some(num)
}
fn main() -> Result<(), lexopt::Error> {
use lexopt::prelude::*;
let mut parser = lexopt::Parser::from_env();
loop {
if let Some(num) = parse_dashnum(&mut parser) {
println!("Got number {}", num);
} else if let Some(arg) = parser.next()? {
match arg {
Short('f') | Long("follow") => {
println!("Got --follow");
}
Short('n') | Long("number") => {
let num: u64 = parser.value()?.parse()?;
println!("Got number {}", num);
}
Value(path) => {
let path = PathBuf::from(path);
println!("Got file {}", path.display());
}
_ => return Err(arg.unexpected()),
}
} else {
break;
}
}
Ok(())
}