feat(lib): add doom-plist-{map,map*}

lisp/lib/plist.el

@@ -26,6 +26,36 @@
       (cadr val)
     nil-value))
 
+;;;###autoload
+(defun doom-plist-map (fn plist)
+  "Map FN on each keyword/value pair in PLIST.
+
+FN is a function that takes two arguments: a keyword and value, and its return
+values are accumulated ala `mapcar'."
+  (cl-loop for (key val) on plist by #'cddr
+           while (keywordp key)
+           do (plist-put plist key (funcall fn key val))))
+
+;;;###autoload
+(defun doom-plist-map* (fn vplist)
+  "Apply FN to each variadic property in VPLIST.
+
+FN is a variadic function, whose first argument is the keyword and the rest the
+values that follow (until the next keyword). Its return value is accumulated ala
+`mapcar'.
+
+VPLIST is a variadic-property list (a plist whose key may be followed by one or
+more values)."
+  (let ((vplist (copy-sequence vplist))
+        results)
+    (while vplist
+      (let ((prop (pop vplist))
+            vals)
+        (while (and vplist (not (keywordp (car vplist))))
+          (push (pop vplist) vals))
+        (push (funcall fn prop (nreverse vals)) results)))
+    (nreverse results)))
+
 ;;;###autoload
 (defun doom-plist-merge (from-plist to-plist)
   "Non-destructively merge FROM-PLIST onto TO-PLIST"