Method concat

std/re/src/main/parser.rs:59–72

A run of quantified atoms until pipe, close paren, or end. */

(&mut self)

    /* A run of quantified atoms until pipe, close paren, or end. */
    fn concat(&mut self) -> Result<Node, ParseError> {
        let mut items = Vec::new();
        loop {
            match self.peek() {
                None | Some('|') | Some(')') => break,
                _ => items.push(self.quantified()?),
            }
        }
        match items.len() {
            0 => Ok(Node::Empty),
            1 => Ok(items.pop().unwrap()),
            _ => Ok(Node::Concat(items)),
        }
    }

    /* An atom plus optional repetition operator. */
    fn quantified(&mut self) -> Result<Node, ParseError> {