feature: updateWithKey(f, k, o).

updates the value if 'k' key is in the object.
the function 'f' will receive the pair (k, v)
as arguments.

Author: diasbruno

readme.md

@@ -8,6 +8,12 @@ Simple objects utilities.
 update(f : Any -> Any, k : String, o : Object) -> Object
 
 // Update the value of key 'k' if present.
+
+
+updateWithKey(f : (String, Any) -> Any, k : String, o : Object) -> Object
+
+// Update the value of key 'k' if present.
+// Function 'f' will receive the pair (k, v) and must return the new value of 'k'.
 ```
 
 ## license

src/index.js

@@ -3,3 +3,9 @@ export function update(f, k, o) {
   o[k] = f(o[k]);
   return o;
 }
+
+export function updateWithKey(f, k, o) {
+  if (!o[k]) return o;
+  o[k] = f(k, o[k]);
+  return o;
+}

tests/index.js

@@ -8,4 +8,12 @@ describe("objects", () => {
       c: 1
     });
   });
+
+  it("updateWithKey(f, k, o)", () => {
+    const obj = { a: "b", c: 1 };
+    O.updateWithKey((k, v) => k + v, "a", obj).should.be.eql({
+      a: "ab",
+      c: 1
+    });
+  });
 });