Added map and map-into

diff --git a/src/js.lisp b/src/js.lisp
index d112c0a..7e1edde 100644 (file)
--- a/src/js.lisp
+++ b/src/js.lisp
@@ -1066,6 +1066,37 @@ vice-versa.")
        (let ((,var (aref ,arrvar ,idx)))
          ,@body)))))
 
+(defjsmacro map-into (function array)
+  "Call FUNCTION on each element in ARRAY, replace element with the return value."
+  ;; be friendly to both (map-into 'foo array) and (map-into foo array) calls
+  (when (and (listp function)
+             (eq 'quote (first function)))
+    (setf function (eval function)))
+  (with-unique-js-names (arrvar idx fn)
+    `((lambda ()
+        (let ((,arrvar ,array)
+              (,fn ,function))
+          (do ((,idx 0 (1+ ,idx)))
+              ((>= ,idx (slot-value ,arrvar 'length)))
+            (setf (aref ,arrvar ,idx) (,fn (aref ,arrvar ,idx)))))
+        (return array)))))
+
+(defjsmacro map (function array)
+  "Call FUNCTION on each element in ARRAY and return the returned values in a new array."
+  ;; be friendly to both (map 'foo array) and (map foo array) calls
+  (when (and (listp function)
+             (eq 'quote (first function)))
+    (setf function (eval function)))
+  (with-unique-js-names (arrvar result idx fn)
+    `((lambda ()
+        (let ((,arrvar ,array)
+              (,fn ,function)
+              (,result (make-array (slot-value ,arrvar 'length))))
+          (do ((,idx 0 (1+ ,idx)))
+              ((>= ,idx (slot-value ,arrvar 'length)))
+            (setf (aref ,result ,idx) (,fn (aref ,arrvar ,idx)))))
+        (return ,result)))))
+
 (defmethod js-to-statement-strings ((for js-for) start-pos)
   (let* ((init (dwim-join (mapcar #'(lambda (x)
                                      (dwim-join (list (list (symbol-to-js (first (var-names x))))