Check if every preprocessing lexeme in a list is a token or newline.
(plexeme-list-token/newline-p x) → std::bool
This is an ordinary std::deflist. It is
"loose" in that it does not care whether
Function:
(defun plexeme-list-token/newline-p (x) (declare (xargs :guard (plexeme-listp x))) (if (consp x) (and (plexeme-token/newline-p (car x)) (plexeme-list-token/newline-p (cdr x))) t))