New function `configuration-layer/layer-declaredp`

core/configuration-layer.el

@@ -153,18 +153,22 @@ for that layer."
           (push (cons (intern f) dir) result)))
       result)))
 
-(defun configuration-layer//declare-layer (sym)
-  "Declare a layer with SYM name (symbol). Return a cons cell (symbol . plist)
+(defun configuration-layer//declare-layer (name)
+  "Declare a layer with NAME symbol. Return a cons cell (symbol . plist)
 where `symbol' is the name of the layer and `plist' is a property list with
 the following keys:
 - `:dir'     the absolute path to the base directory of the layer.
 - `:ext-dir' the absolute path to the directory containing the extensions."
-  (let* ((sym-name (symbol-name sym))
-         (base-dir (configuration-layer/get-layer-path sym))
-         (dir (format "%s%s/" base-dir sym-name))
+  (let* ((namestr (symbol-name name))
+         (base-dir (configuration-layer/get-layer-path name))
+         (dir (format "%s%s/" base-dir namestr))
          (ext-dir (format "%sextensions/" dir)))
     (when (and base-dir (file-exists-p dir))
-        (cons sym (list :dir dir :ext-dir ext-dir)))))
+        (cons name (list :dir dir :ext-dir ext-dir)))))
+
+(defun configuration-layer/layer-declaredp (layer)
+  "Return non-nil if LAYER symbol corresponds to a declared layer."
+  (ht-contains? configuration-layer-all-packages layer))
 
 (defun configuration-layer/get-layers-list ()
   "Return a list of all discovered layer symbols."

spacemacs/keybindings.el

@@ -102,7 +102,7 @@
 (evil-leader/set-key "cC" 'compile)
 (evil-leader/set-key "cr" 'recompile)
 ;; narrow & widen -------------------------------------------------------------
-(unless (ht-contains? configuration-layer-all-packages 'fancy-narrow)
+(unless (configuration-layer/layer-declaredp 'fancy-narrow)
   (evil-leader/set-key
     "nr" 'narrow-to-region
     "np" 'narrow-to-page