[Common Lisp] SQL

こんなふうに SQL を書くのはどうだろう？

(defun |#q-quote-reader| (stream char)
  (declare (ignore char))
  (with-output-to-string (out)
    (loop for c = (read-char stream t nil t)
          until (and (char= #\' c)
                     (char/= #\' (peek-char nil stream nil #\a t)))
          do (progn
               (write-char c out)
               (when (char= c #\')
                 (read-char stream))))))

(defun |#q-reader| (stream sub-char numarg)
  (declare (ignore sub-char numarg))
  (let ((*readtable* (copy-readtable nil)))
    (set-macro-character #\, {(declare (ignore _x _y)) '|,|})
    (set-macro-character #\' #'|#q-quote-reader|)
    `(quote ,(read stream t nil t))))

(set-dispatch-macro-character #\# #\q #'|#q-reader|)


#q(select item, price, 'Hello ''World''' as hello from order-header)
;; => (SELECT ITEM YOU::|,| PRICE YOU::|,| "Hello 'World'" AS HELLO FROM ORDER-HEADER)