#-:triple-quoted-typedoc
(defun read-tdl-type-comment (istream name)
  ;;; enclosed in """..."""s as in Python - called when we've just peeked a "
  (let ((start-position (file-position istream))) ; record in case the comment isn't closed
    ;; first read the peeked double quote, and then the only legal following characters are
    ;; two more double quotes
    (read-char istream)
    (cond
      ((and (eql (read-char istream nil 'eof) #\")
            (eql (read-char istream nil 'eof) #\")))
      (t
        (lkb-read-cerror istream 
          "Need three double-quote marks for type comment for ~A (comment start at ~A)" 
          name start-position)))
    ;; accumulate characters until encountering 3 consecutive non-escaped double quotes
    ;; !!! this is not a general Python string reader: only \newline, \\, \' and \" are
    ;; recognised as escape sequences
    (loop 
      for c = (read-char istream nil 'eof)
      with ndouble = 0
      with chars = nil
      do
      (block do
        (case c
          (eof
            (lkb-read-cerror istream 
              "File ended in middle of type comment for ~A (comment start at ~A)" 
              name start-position)
            (return ""))
          (#\\
            (setq ndouble 0)
            (let ((next (peek-char nil istream nil 'eof)))
              (case next
                (#\newline (read-char istream nil 'eof) (return-from do))
                ((#\\ #\" #\') (setq c (read-char istream nil 'eof)))
                (t nil))))
          (#\"
            (incf ndouble)
            (when (= ndouble 3) (loop-finish)))
          (t
            (setq ndouble 0)))
        (push c chars))
      finally
      (return (coerce (nreverse (cddr chars)) 'string))))) ; last 2 chars were the pre-final "s