Shared via Rust Playground

playground.rs

trait Substring {
    fn substr(&self, start_index: u32, length: u32) -> &str;
    fn substring(&self, start_index: u32) -> &str;
}

impl Substring for str {
    fn substr(&self, start_index: u32, length: u32) -> &str {
        if length == 0 { return ""; }
        if start_index == 0 && length == self.len() as u32 { return &self; }
        return &self[start_index as usize .. start_index as usize + length as usize];
    }
    
    fn substring(&self, start_index: u32) -> &str {
        return &self.substr(start_index, self.len() as u32 - start_index);
    }
}



fn main() {
    let string = "The quick brown fox jumped over the lazy dog";
    println!("Substring: {}", string.substring(5));
}