src/save-restore.lisp

   1
   2 (in-package :lineal)
   3
   4 (defgeneric persist-to (v strm))
   5 (defmethod persist-to ((k number) strm)
   6   (format strm " ~S" k))
   7
   8 (defmethod persist-to ((u tuple) strm)
   9   (format strm " (vcat~{ ~S~})" (tuple-elems u)))
  10
  11 (defmethod persist-to ((a mtrix) strm)
  12   (format strm " (vcat~{ (cat~{ ~S~})~})"
  13           (mtrix-elems a)))
  14
  15 (defun persist-var-to (k strm)
  16   (format strm "(store ~S" k)
  17   (persist-to
  18     (symbol-value (find-symbol k :lineal.client-vars))
  19     strm)
  20   (princ ")" strm)
  21   (terpri strm))
  22
  23 ;V Write all variables in *clent-vars* to the stream  V
  24 ;V in a special format which uses lineal's calculator V
  25 ;V syntax. For example, if we have a                  V
  26 ;V number a, vector b, and matrix c, where            V
  27 ; a = 17
  28 ; b = (1, 2, 3)
  29 ;     [1 2]
  30 ; c = [3 4]
  31 ;V the data written to the stream is                  V
  32 ; (store "a" 17)
  33 ; (store "b" (vcat 1 2 3))
  34 ; (store "c" (vcat (cat 1 2) (cat 3 4))))
  35 ;
  36 (defun save-to-stream (strm)
  37   (loop :for k :in
  38         (append *saved-numbers*
  39                 *saved-tuples* *saved-matrices*)
  40         :do (persist-var-to k strm)))
  41
  42 (defun restore-from-stream (strm)
  43   (let ((result (process-input-from-stream strm nil)))
  44     (if (stringp result)
  45       (format nil "ERROR  ~A" result)
  46       "Variables successfully restored.")))
  47
  48 ;V Save a session capture file.V
  49 (defun local-capture
  50   (&optional
  51     (file (make-pathname :name "captured_session")))
  52   (with-open-file
  53     (strm file :direction :output
  54           :if-exists :supersede)
  55     (save-to-stream strm)))
  56
  57 ;V Restore from a capture file.V
  58 (defun local-restore
  59   (&optional
  60     (file (make-pathname :name "captured_session")))
  61   (handler-case
  62     (with-open-file (strm file :direction :input
  63                           :if-does-not-exist nil)
  64       (if strm (restore-from-stream strm)
  65         "File does not exist."))
  66     (error (condit)
  67            (declare (ignore condit))
  68            "Something went horribly wrong.")))
  69