(libload "./readline")

(defvar history-file
  (concat-fname (getenv "HOME") "/.mal_history"))

(de blankp (line)
  (regex-match "[ \t\n]*" line))

(de load-history ()
  (let ((fd (open-read history-file)))
    (when fd
      (each ((line (read-lines fd)))
        (when (not (blankp line))
          (add-history line))))))

(de add-to-history (line)
  (add-history line)
  (writing (open-append history-file)
    (printf "%s\n" line)))

(de repl (prompt)
  (load-history)
  (let ((input nil))
    (while (setq input (readline prompt))
      (when (not (blankp input))
        (printf "%s\n" input)
        (add-to-history input)))
    (printf "\n")))

(repl "> ")