diff --git a/lib/coffeescript/rewriter.js b/lib/coffeescript/rewriter.js
index 69b62aea..69042ecc 100644
--- a/lib/coffeescript/rewriter.js
+++ b/lib/coffeescript/rewriter.js
@@ -281,7 +281,7 @@
         stack = [];
         start = null;
         return this.scanTokens(function(token, i, tokens) {
-          var endImplicitCall, endImplicitObject, forward, implicitObjectContinues, inImplicit, inImplicitCall, inImplicitControl, inImplicitObject, isImplicit, isImplicitCall, isImplicitObject, k, newLine, nextTag, nextToken, offset, prevTag, prevToken, ref, ref1, s, sameLine, stackIdx, stackItem, stackTag, stackTop, startIdx, startImplicitCall, startImplicitObject, startsLine, tag;
+          var endImplicitCall, endImplicitObject, forward, implicitObjectContinues, inImplicit, inImplicitCall, inImplicitControl, inImplicitObject, isImplicit, isImplicitCall, isImplicitObject, k, newLine, nextTag, nextToken, offset, prevTag, prevToken, ref, ref1, ref2, s, sameLine, stackIdx, stackItem, stackTag, stackTop, startIdx, startImplicitCall, startImplicitObject, startsLine, tag;
           [tag] = token;
           [prevTag] = prevToken = i > 0 ? tokens[i - 1] : [];
           [nextTag] = nextToken = i < tokens.length - 1 ? tokens[i + 1] : [];
@@ -539,7 +539,7 @@
 
           //     f a, b: c, d: e, f, g: h: i, j
 
-          if (tag === ',' && !this.looksObjectish(i + 1) && inImplicitObject() && (nextTag !== 'TERMINATOR' || !this.looksObjectish(i + 2))) {
+          if (tag === ',' && !this.looksObjectish(i + 1) && inImplicitObject() && !((ref2 = this.tag(i + 2)) === 'FOROF' || ref2 === 'FORIN') && (nextTag !== 'TERMINATOR' || !this.looksObjectish(i + 2))) {
             // When nextTag is OUTDENT the comma is insignificant and
             // should just be ignored so embed it in the implicit object.
 
diff --git a/src/rewriter.coffee b/src/rewriter.coffee
index a997f58c..7808d9e9 100644
--- a/src/rewriter.coffee
+++ b/src/rewriter.coffee
@@ -377,7 +377,7 @@ exports.Rewriter = class Rewriter
       #
       #     f a, b: c, d: e, f, g: h: i, j
       #
-      if tag is ',' and not @looksObjectish(i + 1) and inImplicitObject() and
+      if tag is ',' and not @looksObjectish(i + 1) and inImplicitObject() and not (@tag(i + 2) in ['FOROF', 'FORIN']) and
          (nextTag isnt 'TERMINATOR' or not @looksObjectish(i + 2))
         # When nextTag is OUTDENT the comma is insignificant and
         # should just be ignored so embed it in the implicit object.
diff --git a/test/objects.coffee b/test/objects.coffee
index 43c757c5..4cd9496c 100644
--- a/test/objects.coffee
+++ b/test/objects.coffee
@@ -652,20 +652,22 @@ test "#4544: Postfix conditionals in first line of implicit object literals", ->
 test "#4579: Postfix for/while/until in first line of implicit object literals", ->
   two =
     foo:
-      bar: x for x in [1, 2, 3]
+      bar1: x for x in [1, 2, 3]
+      bar2: x + y for x, y in [1, 2, 3]
       baz: 1337
-  arrayEq [1, 2, 3], two.foo.bar
+  arrayEq [1, 2, 3], two.foo.bar1
+  arrayEq [1, 3, 5], two.foo.bar2
   eq 1337, two.foo.baz
 
   f = (x) -> x
 
   three =
     foo: f
-      # Uncomment when #4580 is fixed
-      # bar: x + y for x, y of a: 'b', c: 'd'
-      bar: x + 'c' for x of a: 1, b: 2
+      bar1: x + y for x, y of a: 'b', c: 'd'
+      bar2: x + 'c' for x of a: 1, b: 2
       baz: 1337
-  arrayEq ['ac', 'bc'], three.foo.bar
+  arrayEq ['ab', 'cd'], three.foo.bar1
+  arrayEq ['ac', 'bc'], three.foo.bar2
   eq 1337, three.foo.baz
 
   four =
@@ -696,4 +698,3 @@ test "#4579: Postfix for/while/until in first line of implicit object literals",
       baz: 1337
   arrayEq [4, 3, 2, 1, 0], six.foo.bar
   eq 1337, six.foo.baz
-