pub trait Tokens {
    type Error;
    // Required methods
    fn peek(
        &mut self,
    ) -> Result<Meta<Option<&Token>, Span>, Meta<Self::Error, Span>>;
    fn next(
        &mut self,
    ) -> Result<Meta<Option<Token>, Span>, Meta<Self::Error, Span>>;
    fn last(&self) -> Span;
}Expand description
Fallible tokens iterator with lookahead.