Split string at regex and keep seperator

split_seperator_keep.rs

use regex::Regex; // 1.1.8

fn split_keep<'a>(r: &Regex, text: &'a str) -> Vec<&'a str> {
    let mut result = Vec::new();
    let mut last = 0;
    for (index, matched) in text.match_indices(r) {
        if last != index {
            result.push(&text[last..index]);
        }
        result.push(matched);
        last = index + matched.len();
    }
    if last < text.len() {
        result.push(&text[last..]);
    }
    result
}

fn main() {
    let seperator = Regex::new(r"(\[[^]]+])").expect("Invalid regex");
    let splits = split_keep(&seperator, "[abc]  content\n[xyz] next line");
    for split in splits.chunks(2).map(|x| format!("{}{}", x[0], x[1])){
        println!("XX: {:?}\n\n", split);
    }
}