// 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"(?m)^(?!(?:[^A\n]*A){2})(?!(?:[^B\n]*B){3})(?!(?:[^C\n]*C){2})(?!(?:[^D\n]*D){2})(?:[ABCD](?:\s|$)){3}").unwrap();
let string = "# These are valid:
A B C
A B B
B C B
D A B
# These are invalid:
A A B
B B B";
// result will be an iterator over tuples containing the start and end indices for each match in the string
let result = regex.captures_iter(string);
for mat in result {
println!("{:?}", mat);
}
}
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/