// include the latest version of the regex crate in your Cargo.toml
extern crate regex;
use regex::Regex;
fn main() {
let regex = Regex::new(r"(?is)Diagnostic-Code:\s+?(.*)").unwrap();
let string = "Diagnostic-Code: smtp; 550-5.1.1 The email account that you tried to reach does
not exist. Please try 550-5.1.1 double-checking the recipient's email
address for typos or 550-5.1.1 unnecessary spaces. Learn more at 550 5.1.1
https://support.google.com/mail/?p=NoSuchUser 63si4621095ybi.465 - gsmtp";
// result will be a tuple containing the start and end indices for the first match in the string
let result = regex.captures(string);
let (start, end) = match result {
Some((s, e)) => (s, e),
None => {
// ...
}
};
println!("{}", &string[start, end]);
}
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Rust, please visit: https://docs.rs/regex/latest/regex/