Convert s-expression backend functions to methods

They are also renamed to match the names of the generic functions.

doc/manual.info

@@ -262,7 +262,7 @@ The next one was released in v0.5. Till then, any time the @uref{../elisp/chrono
 After the optimization@dots{}
 @enumerate
 @item
-Two backend functions (@uref{../elisp/chronometrist-sexp.el, @samp{chronometrist-sexp-new}} and @uref{../elisp/chronometrist-sexp.el, @samp{chronometrist-sexp-replace-last}}) were modified to set a flag (@uref{../elisp/chronometrist.el, @samp{chronometrist--inhibit-read-p}}) before saving the file.
+Two backend functions (@uref{../elisp/chronometrist-sexp.el, @samp{chronometrist-new}} and @uref{../elisp/chronometrist-sexp.el, @samp{chronometrist-replace-last}}) were modified to set a flag (@uref{../elisp/chronometrist.el, @samp{chronometrist--inhibit-read-p}}) before saving the file.
 @item
 If this flag is non-nil, @uref{../elisp/chronometrist.el, @samp{chronometrist-refresh-file}} skips the expensive calls to @samp{chronometrist-events-populate}, @samp{chronometrist-tasks-from-table}, and @samp{chronometrist-tags-history-populate}, and resets the flag.
 @item
@@ -1106,33 +1106,35 @@ Function - chronometrist-goal-on-file-change ()
 
 @enumerate
 @item
+Class - chronometrist-sexp
+@item
+Object - chronometrist-sexp
+@item
 Custom variable - chronometrist-sexp-pretty-print-function
 @item
 Macro - chronometrist-sexp-in-file (file &rest body)
 @item
-Function - chronometrist-sexp-open-log ()
+Method - chronometrist-to-hash ((backend chronometrist-sexp) table)
 @item
-Function - chronometrist-sexp-between (&optional (ts-beg (chronometrist-date)) (ts-end (ts-adjust 'day +1 (chronometrist-date))))
+Method - chronometrist-from-hash ((backend chronometrist-sexp) table)
 @item
-Function - chronometrist-sexp-query-till (&optional (date (chronometrist-date)))
+Method - chronometrist-open-log ((backend chronometrist-sexp))
 @item
-Function - chronometrist-sexp-last ()
+Method - chronometrist-last ((backend chronometrist-sexp))
 @itemize
 @item
 -> plist
 @end itemize
 @item
-Function - chronometrist-sexp-current-task ()
+Method - chronometrist-current-task ((backend chronometrist-sexp))
 @item
-Function - chronometrist-sexp-events-populate ()
+Method - chronometrist-create-file ((backend chronometrist-sexp))
 @item
-Function - chronometrist-sexp-create-file ()
-@item
-Function - chronometrist-sexp-new (plist &optional (buffer (find-file-noselect chronometrist-file)))
+Method - chronometrist-new (((backend chronometrist-sexp)) plist)
 @item
 Function - chronometrist-sexp-delete-list (&optional arg)
 @item
-Function - chronometrist-sexp-replace-last (plist)
+Method - chronometrist-replace-last (((backend chronometrist-sexp)) plist)
 @item
 Command - chronometrist-sexp-reindent-buffer ()
 @end enumerate

doc/manual.org

@@ -87,7 +87,7 @@ One of the earliest 'optimizations' of great importance turned out to simply be
 The next one was released in v0.5. Till then, any time the [[file:../elisp/chronometrist-custom.el::defcustom chronometrist-file (][=chronometrist-file=]] was modified, we'd clear the [[file:../elisp/chronometrist-events.el::defvar chronometrist-events (][=chronometrist-events=]] hash table and read data into it again. The reading itself is nearly-instant, even with ~2 years' worth of data [fn:1] (it uses Emacs' [[elisp:(describe-function 'read)][=read=]], after all), but the splitting of [[* Midnight-spanning events][midnight-spanning events]] is the real performance killer.
 
 After the optimization...
-1. Two backend functions ([[file:../elisp/chronometrist-sexp.el::cl-defun chronometrist-sexp-new (][=chronometrist-sexp-new=]] and [[file:../elisp/chronometrist-sexp.el::defun chronometrist-sexp-replace-last (][=chronometrist-sexp-replace-last=]]) were modified to set a flag ([[file:../elisp/chronometrist.el::defvar chronometrist--inhibit-read-p ][=chronometrist--inhibit-read-p=]]) before saving the file.
+1. Two backend functions ([[file:../elisp/chronometrist-sexp.el::cl-defmethod chronometrist-new (][=chronometrist-new=]] and [[file:../elisp/chronometrist-sexp.el::cl-defmethod chronometrist-replace-last (][=chronometrist-replace-last=]]) were modified to set a flag ([[file:../elisp/chronometrist.el::defvar chronometrist--inhibit-read-p ][=chronometrist--inhibit-read-p=]]) before saving the file.
 2. If this flag is non-nil, [[file:../elisp/chronometrist.el::defun chronometrist-refresh-file (][=chronometrist-refresh-file=]] skips the expensive calls to =chronometrist-events-populate=, =chronometrist-tasks-from-table=, and =chronometrist-tags-history-populate=, and resets the flag.
 3. Instead, the aforementioned backend functions modify the relevant variables - =chronometrist-events=, =chronometrist-task-list=, and =chronometrist-tags-history= - via...
    * =chronometrist-events-add= / =chronometrist-events-replace-last=
@@ -455,20 +455,21 @@ Each of these has a corresponding function to clear it and fill it with values -
 13. Function - chronometrist-goal-on-file-change ()
 
 ** chronometrist-sexp
-1.  Custom variable - chronometrist-sexp-pretty-print-function
-2.  Macro - chronometrist-sexp-in-file (file &rest body)
-3.  Function - chronometrist-sexp-open-log ()
-4.  Function - chronometrist-sexp-between (&optional (ts-beg (chronometrist-date)) (ts-end (ts-adjust 'day +1 (chronometrist-date))))
-5.  Function - chronometrist-sexp-query-till (&optional (date (chronometrist-date)))
-6.  Function - chronometrist-sexp-last ()
-    * -> plist
-7.  Function - chronometrist-sexp-current-task ()
-8.  Function - chronometrist-sexp-events-populate ()
-9.  Function - chronometrist-sexp-create-file ()
-10. Function - chronometrist-sexp-new (plist &optional (buffer (find-file-noselect chronometrist-file)))
-11. Function - chronometrist-sexp-delete-list (&optional arg)
-12. Function - chronometrist-sexp-replace-last (plist)
-13. Command - chronometrist-sexp-reindent-buffer ()
+1. Class - chronometrist-sexp
+2. Object - chronometrist-sexp
+3. Custom variable - chronometrist-sexp-pretty-print-function
+4. Macro - chronometrist-sexp-in-file (file &rest body)
+5. Method - chronometrist-to-hash ((backend chronometrist-sexp) table)
+5. Method - chronometrist-from-hash ((backend chronometrist-sexp) table)
+5. Method - chronometrist-open-log ((backend chronometrist-sexp))
+8. Method - chronometrist-last ((backend chronometrist-sexp))
+   * -> plist
+9. Method - chronometrist-current-task ((backend chronometrist-sexp))
+11. Method - chronometrist-create-file ((backend chronometrist-sexp))
+12. Method - chronometrist-new (((backend chronometrist-sexp)) plist)
+13. Function - chronometrist-sexp-delete-list (&optional arg)
+14. Method - chronometrist-replace-last (((backend chronometrist-sexp)) plist)
+15. Command - chronometrist-sexp-reindent-buffer ()
 
 # Local Variables:
 # org-link-file-path-type: relative

elisp/chronometrist-backend.el

@@ -19,6 +19,9 @@
     "The extension used by a file of this backend, without a leading period."
     :initform "")))
 
+(defvar chronometrist-current-backend nil
+  "The current backend in use.")
+
 (defvar chronometrist-backends nil
   "List of enabled backends.")
 

elisp/chronometrist-common.el

@@ -61,7 +61,7 @@ file.")
 
 (defun chronometrist-current-task ()
   "Return the name of the currently clocked-in task, or nil if not clocked in."
-  (chronometrist-sexp-current-task))
+  (chronometrist-current-task chronometrist-current-backend))
 
 (cl-defun chronometrist-format-time (seconds &optional (blank "   "))
   "Format SECONDS as a string suitable for display in Chronometrist buffers.

elisp/chronometrist-key-values.el

@@ -96,7 +96,7 @@ be removed."
                             new-kvs
                             `(:start ,old-start)
                             (when old-stop `(:stop  ,old-stop)))))
-    (chronometrist-sexp-replace-last plist)))
+    (chronometrist-replace-last chronometrist-current-backend plist)))
 
 ;;;; TAGS ;;;;
 (defvar chronometrist-tags-history (make-hash-table :test #'equal)

elisp/chronometrist-queries.el

@@ -22,7 +22,7 @@
 
 (defun chronometrist-last ()
   "Return the last entry from `chronometrist-file' as a plist."
-  (chronometrist-sexp-last))
+  (chronometrist-last chronometrist-current-backend))
 
 (cl-defun chronometrist-task-time-one-day (task &optional (ts (ts-now)))
   "Return total time spent on TASK today or (if supplied) on timestamp TS.

elisp/chronometrist-report.el

@@ -227,7 +227,7 @@ current week. Otherwise, display data from the week specified by
              (kill-buffer buffer))
             (t (unless keep-date
                  (setq chronometrist-report--ui-date nil))
-               (chronometrist-common-create-file)
+               (chronometrist-create-file chronometrist-current-backend)
                (chronometrist-report-mode)
                (switch-to-buffer buffer)
                (chronometrist-report-refresh-file nil)

elisp/chronometrist-sexp.el

@@ -33,32 +33,10 @@ neatly), or falls back to `pp' if it isn't."
   `(with-current-buffer (find-file-noselect ,file)
      (save-excursion ,@body)))
 
-;;;; Queries
-(defun chronometrist-sexp-open-log ()
-  "Open `chronometrist-file' in another window."
-  (find-file-other-window chronometrist-file)
-  (goto-char (point-max)))
+;; # Migration #
+(cl-defmethod chronometrist-to-hash ((backend chronometrist-sexp) table))
 
-(defun chronometrist-sexp-last ()
-  "Return last s-expression from `chronometrist-file'."
-  (chronometrist-sexp-in-file chronometrist-file
-    (goto-char (point-max))
-    (backward-list)
-    (ignore-errors (read (current-buffer)))))
-
-(defun chronometrist-sexp-current-task ()
-  "Return the name of the currently clocked-in task, or nil if not clocked in."
-  (let ((last-event (chronometrist-sexp-last)))
-    (if (plist-member last-event :stop)
-        nil
-      (plist-get last-event :name))))
-
-(defun chronometrist-sexp-events-populate ()
-  "Populate hash table `chronometrist-events'.
-The data is acquired from `chronometrist-file'.
-
-Return final number of events read from file, or nil if there
-were none."
+(cl-defmethod chronometrist-from-hash ((backend chronometrist-sexp) table)
   (chronometrist-sexp-in-file chronometrist-file
     (goto-char (point-min))
     (let ((index 0) expr pending-expr)
@@ -84,15 +62,30 @@ were none."
                    chronometrist-events)))
       (unless (zerop index) index))))
 
-;;;; Modifications
-(defun chronometrist-sexp-create-file ()
-  "Create `chronometrist-file' if it doesn't already exist."
+;; # Queries #
+(cl-defmethod chronometrist-open-log ((backend chronometrist-sexp))
+  (find-file-other-window chronometrist-file)
+  (goto-char (point-max)))
+
+(cl-defmethod chronometrist-last ((backend chronometrist-sexp))
+  (chronometrist-sexp-in-file chronometrist-file
+    (goto-char (point-max))
+    (backward-list)
+    (ignore-errors (read (current-buffer)))))
+
+(cl-defmethod chronometrist-current-task ((backend chronometrist-sexp))
+  (let ((last-event (chronometrist-last backend)))
+    (if (plist-member last-event :stop)
+        nil
+      (plist-get last-event :name))))
+
+;; # Modifications #
+(cl-defmethod chronometrist-create-file ((backend chronometrist-sexp))
   (unless (file-exists-p chronometrist-file)
     (with-current-buffer (find-file-noselect chronometrist-file)
       (write-file chronometrist-file))))
 
-(cl-defun chronometrist-sexp-new (plist)
-  "Add new PLIST at the end of `chronometrist-file'."
+(cl-defmethod chronometrist-new ((backend chronometrist-sexp) plist)
   (chronometrist-sexp-in-file chronometrist-file
     (goto-char (point-max))
     ;; If we're adding the first s-exp in the file, don't add a
@@ -114,8 +107,7 @@ were none."
     (forward-sexp (or arg 1))
     (delete-region point-1 (point))))
 
-(defun chronometrist-sexp-replace-last (plist)
-  "Replace the last s-expression in `chronometrist-file' with PLIST."
+(cl-defmethod chronometrist-replace-last ((backend chronometrist-sexp) plist)
   (chronometrist-sexp-in-file chronometrist-file
     (goto-char (point-max))
     (unless (and (bobp) (bolp))
@@ -131,7 +123,7 @@ were none."
     ;; :name should be removed from `chronometrist-task-list', but to ascertain
     ;; that condition we would have to either read the entire file or
     ;; map over the hash table, defeating the optimization. Thus, we
-    ;; don't update `chronometrist-task-list' here (unlike `chronometrist-sexp-new')
+    ;; don't update `chronometrist-task-list' here (unlike `chronometrist-new')
     (chronometrist-tags-history-replace-last plist)
     (setq chronometrist--inhibit-read-p t)
     (save-buffer)))

elisp/chronometrist-statistics.el

@@ -260,7 +260,7 @@ specified by `chronometrist-statistics--ui-state'."
                (setq chronometrist-statistics--ui-state `(:mode week
                                         :start ,week-start
                                         :end   ,week-end)))
-             (chronometrist-common-create-file)
+             (chronometrist-create-file chronometrist-current-backend)
              (chronometrist-statistics-mode)
              (switch-to-buffer buffer)
              (chronometrist-statistics-refresh))))))

elisp/chronometrist.el

@@ -89,11 +89,7 @@
 Argument _BUTTON is for the purpose of using this command as a
 button action."
   (interactive)
-  (chronometrist-sexp-open-log))
-
-(defun chronometrist-common-create-file ()
-  "Create `chronometrist-file' if it doesn't already exist."
-  (chronometrist-sexp-create-file))
+  (chronometrist-sexp-open-log chronometrist-current-backend))
 
 (defun chronometrist-task-active? (task)
   "Return t if TASK is currently clocked in, else nil."
@@ -228,7 +224,7 @@ Argument _FS-EVENT is ignored."
 TASK is the name of the task, a string. PREFIX is ignored."
   (interactive "P")
   (let ((plist `(:name ,task :start ,(chronometrist-format-time-iso8601))))
-    (chronometrist-sexp-new plist)
+    (chronometrist-new chronometrist-current-backend plist)
     (chronometrist-refresh)))
 
 (defun chronometrist-out (&optional _prefix)
@@ -236,7 +232,7 @@ TASK is the name of the task, a string. PREFIX is ignored."
 PREFIX is ignored."
   (interactive "P")
   (let ((plist (plist-put (chronometrist-last) :stop (chronometrist-format-time-iso8601))))
-    (chronometrist-sexp-replace-last plist)))
+    (chronometrist-replace-last plist)))
 
 ;; ## HOOKS ##
 (defvar chronometrist-mode-hook nil
@@ -443,7 +439,7 @@ If numeric argument ARG is 2, run `chronometrist-statistics'."
           (cond ((or (not (file-exists-p chronometrist-file))
                      (chronometrist-common-file-empty-p chronometrist-file))
                  ;; first run
-                 (chronometrist-common-create-file)
+                 (chronometrist-create-file chronometrist-current-backend)
                  (let ((inhibit-read-only t))
                    (chronometrist-common-clear-buffer buffer)
                    (insert "Welcome to Chronometrist! Hit RET to ")