elisp/printer.el

   1 (defun pr-str (form &optional print-readably)
   2   (let ((type (mal-type form))
   3         (value (mal-value form)))
   4     (cond
   5      ((eq type 'nil)
   6       "nil")
   7      ((eq type 'true)
   8       "true")
   9      ((eq type 'false)
  10       "false")
  11      ((eq type 'number)
  12       (number-to-string (mal-value form)))
  13      ((eq type 'string)
  14       (if print-readably
  15           (let ((print-escape-newlines t))
  16             (prin1-to-string value))
  17         value))
  18      ((or (eq type 'symbol) (eq type 'keyword))
  19       (symbol-name value))
  20      ((eq type 'list)
  21       (pr-list value print-readably))
  22      ((eq type 'vector)
  23       (pr-vector value print-readably))
  24      ((eq type 'map)
  25       (pr-map value print-readably))
  26      ((eq type 'fn)
  27       "#<fn>")
  28      ((eq type 'func)
  29       "#<func>")
  30      ((eq type 'atom)
  31       (format "(atom %s)" (mal-value value))))))
  32
  33 (defun pr-list (form print-readably)
  34   (let ((items (mapconcat
  35                 (lambda (item) (pr-str item print-readably))
  36                 form " ")))
  37     (concat "(" items ")")))
  38
  39 (defun pr-vector (form print-readably)
  40   (let ((items (mapconcat
  41                 (lambda (item) (pr-str item print-readably))
  42                 (append form nil) " ")))
  43     (concat "[" items "]")))
  44
  45 (defun pr-map (form print-readably)
  46   (let (pairs)
  47     (maphash
  48      (lambda (key value)
  49        (push (cons (pr-str key print-readably)
  50                    (pr-str value print-readably))
  51              pairs))
  52      form)
  53     (let ((items (mapconcat
  54                   (lambda (item) (concat (car item) " " (cdr item)))
  55                   (nreverse pairs) " ")))
  56       (concat "{" items "}"))))