pub struct Lexer {
    str: String,
    c: usize
}

impl Lexer {
    pub fn get_string(&mut self) -> Option<&str> {
        let w = self.str[self.c..].find(|c: char| c.is_whitespace())? + self.c;
        let t = &self.str[self.c..w];
        self.c = w;
        for c in self.str[self.c..].chars() {
            if !c.is_whitespace() {
                break;
            }
            else {
                self.c += 1
            }
        }

        Some(t)
    }

    pub fn get_rest(&mut self) -> &str {
        &self.str[self.c..]
    }
}