fn type_aliases(&mut self) -> WeldResult<Vec<TypeAlias>> {
        let mut res: Vec<TypeAlias> = Vec::new();
        while *self.peek() == TType {
            res.push(self.type_alias_()?);
        }
        Ok(res)
    }
Parse a list of type aliases starting at the current position.
weld/src/syntax/parser.rs