Use :when as :enable-funcion in tempel-abbrev-mode (#149)

* Added feature: :enable-function

* Use :when instead of :enable-function for tempel-abbrev-mode

tempel.el

@@ -490,25 +490,27 @@ This is meant to be a source in `tempel-template-sources'."
       (unless (equal (car tempel--path-templates) timestamps)
         (setq tempel--path-templates (cons timestamps
                                            (mapcan #'tempel--file-read files))))))
+
   (cl-loop
    for (modes plist . templates) in (cdr tempel--path-templates)
-   if (tempel--condition-p modes plist)
-   append templates))
-
-(defun tempel--condition-p (modes plist)
-  "Return non-nil if one of MODES matches and the PLIST condition is satisfied."
-  (and
-   (cl-loop
-    for m in modes thereis
-    (or (eq m #'fundamental-mode)
-        (derived-mode-p m)
-        (when-let ((remap (alist-get m (bound-and-true-p major-mode-remap-alist))))
-          (derived-mode-p remap))))
-   (or (not (plist-member plist :when))
-       (save-excursion
-         (save-restriction
-           (save-match-data
-             (eval (plist-get plist :when) 'lexical)))))))
+   if (tempel--mode-matches-p modes)
+   collect (list modes plist templates)))
+
+(defun tempel--mode-matches-p (modes)
+  "Return non-nil if one of MODES matches."
+  (cl-loop
+   for m in modes thereis
+   (or (eq m #'fundamental-mode)
+       (derived-mode-p m)
+       (when-let ((remap (alist-get m (bound-and-true-p major-mode-remap-alist))))
+         (derived-mode-p remap)))))
+
+(defun tempel--eval-condition (condition)
+  "Return non-nil if CONDITION is satisfied."
+  (save-excursion
+    (save-restriction
+      (save-match-data
+        (eval condition 'lexical)))))
 
 (defun tempel--templates ()
   "Return templates for current mode."
@@ -523,6 +525,16 @@ This is meant to be a source in `tempel-template-sources'."
        nil))
     result))
 
+
+(defun tempel--enabled-templates ()
+  "Return enabled templates for the current mode."
+  (cl-loop
+     for (modes plist templates) in (tempel--templates)
+     if (tempel--eval-condition (if-let (condition (plist-get plist :when))
+                                    (tempel--eval-condition condition)
+                                  t))
+     append templates))
+
 (defun tempel--region ()
   "Return region bounds."
   (when (use-region-p)
@@ -687,7 +699,7 @@ command."
   (interactive (list t))
   (if interactive
       (tempel--interactive #'tempel-expand)
-    (when-let ((templates (tempel--templates))
+    (when-let ((templates (tempel--enabled-templates))
                (bounds (tempel--prefix-bounds))
                (name (buffer-substring-no-properties
                       (car bounds) (cdr bounds)))
@@ -714,7 +726,7 @@ Capf, otherwise like an interactive completion command."
           (insert tempel-trigger-prefix))
         (tempel--interactive #'tempel-complete))
     (let ((region (tempel--region)))
-      (when-let ((templates (tempel--templates))
+      (when-let ((templates (tempel--enabled-templates))
                  (bounds (or (and (not region) (tempel--prefix-bounds))
                              (and (not tempel-trigger-prefix) (cons (point) (point))))))
         (list (car bounds) (cdr bounds)
@@ -745,7 +757,7 @@ If called interactively, select a template with `completing-read'."
   (interactive (list nil))
   (tempel--insert
    (if (consp template-or-name) template-or-name
-     (let* ((templates (or (tempel--templates)
+     (let* ((templates (or (tempel--enabled-templates)
                            (error "Tempel: No templates for %s" major-mode)))
             (completion-extra-properties
              (and tempel-insert-annotation
@@ -796,16 +808,27 @@ If called interactively, select a template with `completing-read'."
             (default-value 'abbrev-minor-mode-table-alist))
     (kill-local-variable 'abbrev-minor-mode-table-alist))
   (when tempel-abbrev-mode
-    (let ((table (make-abbrev-table)))
-      (dolist (template (tempel--templates))
-        (let* ((name (symbol-name (car template)))
-               (hook (make-symbol name)))
-          (fset hook (apply-partially #'tempel--abbrev-hook name (cdr template)))
-          (put hook 'no-self-insert t)
-          (define-abbrev table name 'Template hook :system t)))
-      (setq-local abbrev-minor-mode-table-alist
-                  (cons `(tempel-abbrev-mode . ,table)
-                        abbrev-minor-mode-table-alist)))))
+      (cl-loop
+       for (modes plist templates) in (tempel--templates)
+       do (let ((table (make-abbrev-table)))
+            (dolist (template templates)
+              (let* ((name (symbol-name (car template)))
+                     (hook (make-symbol name)))
+                (fset hook (apply-partially #'tempel--abbrev-hook name (cdr template)))
+                (put hook 'no-self-insert t)
+                (define-abbrev table name 'Template hook :system t)))
+
+            (when-let (condition (plist-get plist :when))
+              (abbrev-table-put table
+                                :enable-function
+                                (lambda ()
+                                  (tempel--eval-condition condition))))
+
+
+            (setq-local abbrev-minor-mode-table-alist
+                        (cons `(tempel-abbrev-mode . ,table)
+                              abbrev-minor-mode-table-alist))
+            ))))
 
 ;;;###autoload
 (define-globalized-minor-mode global-tempel-abbrev-mode