Method peek

core/src/lexer.rs:761–767

Peeks the upcoming token. It is OK to call this function several times on the same token before extracting it from the lexer.

(&mut self)

    /// It is OK to call this function several times on the same token before extracting it from
    /// the lexer.
    pub fn peek(&mut self) -> Result<&TokenSpan> {
        if self.peeked.is_none() {
            let span = self.read()?;
            self.peeked.replace(span);
        }
        Ok(self.peeked.as_ref().unwrap())
    }

    /// Reads the next token.
    ///