diff --git a/lib/coffee-script/nodes.js b/lib/coffee-script/nodes.js
index f5eb07723a..13bd8dc8d8 100644
--- a/lib/coffee-script/nodes.js
+++ b/lib/coffee-script/nodes.js
@@ -1428,7 +1428,7 @@
     Obj.prototype.children = ['properties'];
 
     Obj.prototype.compileNode = function(o) {
-      var answer, dynamicIndex, hasDynamic, i, idt, indent, j, join, k, key, l, lastNoncom, len1, len2, len3, node, oref, prop, props, ref3, value;
+      var answer, i, idt, indent, j, join, k, key, lastNoncom, len1, len2, node, prop, props, ref3, value;
       props = this.properties;
       if (this.generated) {
         for (j = 0, len1 = props.length; j < len1; j++) {
@@ -1438,34 +1438,14 @@
           }
         }
       }
-      for (dynamicIndex = k = 0, len2 = props.length; k < len2; dynamicIndex = ++k) {
-        prop = props[dynamicIndex];
-        if ((prop.variable || prop).base instanceof Parens) {
-          break;
-        }
-      }
-      hasDynamic = dynamicIndex < props.length;
       idt = o.indent += TAB;
       lastNoncom = this.lastNonComment(this.properties);
       answer = [];
-      if (hasDynamic) {
-        oref = o.scope.freeVariable('obj');
-        answer.push(this.makeCode("(\n" + idt + oref + " = "));
-      }
-      answer.push(this.makeCode("{" + (props.length === 0 || dynamicIndex === 0 ? '}' : '\n')));
-      for (i = l = 0, len3 = props.length; l < len3; i = ++l) {
+      answer.push(this.makeCode("{" + (props.length === 0 ? '}' : '\n')));
+      for (i = k = 0, len2 = props.length; k < len2; i = ++k) {
         prop = props[i];
-        if (i === dynamicIndex) {
-          if (i !== 0) {
-            answer.push(this.makeCode("\n" + idt + "}"));
-          }
-          answer.push(this.makeCode(',\n'));
-        }
-        join = i === props.length - 1 || i === dynamicIndex - 1 ? '' : prop === lastNoncom || prop instanceof Comment ? '\n' : ',\n';
+        join = i === props.length - 1 ? '' : prop === lastNoncom || prop instanceof Comment ? '\n' : ',\n';
         indent = prop instanceof Comment ? '' : idt;
-        if (hasDynamic && i < dynamicIndex) {
-          indent += TAB;
-        }
         if (prop instanceof Assign) {
           if (prop.context !== 'object') {
             prop.operatorToken.error("unexpected " + prop.operatorToken.value);
@@ -1477,22 +1457,15 @@
         if (prop instanceof Value && prop["this"]) {
           prop = new Assign(prop.properties[0].name, prop, 'object');
         }
-        if (!(prop instanceof Comment)) {
-          if (i < dynamicIndex) {
-            if (!(prop instanceof Assign)) {
-              prop = new Assign(prop, prop, 'object');
+        if (!(prop instanceof Comment) && !(prop instanceof Assign)) {
+          if (prop.isComplex()) {
+            ref3 = prop.base.cache(o), key = ref3[0], value = ref3[1];
+            if (key instanceof IdentifierLiteral) {
+              key = new PropertyName(key.value);
             }
+            prop = new Assign(key, value, 'object');
           } else {
-            if (prop instanceof Assign) {
-              key = prop.variable;
-              value = prop.value;
-            } else {
-              ref3 = prop.base.cache(o), key = ref3[0], value = ref3[1];
-              if (key instanceof IdentifierLiteral) {
-                key = new PropertyName(key.value);
-              }
-            }
-            prop = new Assign(new Value(new IdentifierLiteral(oref), [new Access(key)]), value);
+            prop = new Assign(prop, prop, 'object');
           }
         }
         if (indent) {
@@ -1503,14 +1476,10 @@
           answer.push(this.makeCode(join));
         }
       }
-      if (hasDynamic) {
-        answer.push(this.makeCode(",\n" + idt + oref + "\n" + this.tab + ")"));
-      } else {
-        if (props.length !== 0) {
-          answer.push(this.makeCode("\n" + this.tab + "}"));
-        }
+      if (props.length !== 0) {
+        answer.push(this.makeCode("\n" + this.tab + "}"));
       }
-      if (this.front && !hasDynamic) {
+      if (this.front) {
         return this.wrapInBraces(answer);
       } else {
         return answer;
@@ -2193,7 +2162,10 @@
       }
       compiledName = this.variable.compileToFragments(o, LEVEL_LIST);
       if (this.context === 'object') {
-        if (ref8 = fragmentsToText(compiledName), indexOf.call(JS_FORBIDDEN, ref8) >= 0) {
+        if (this.variable.isComplex()) {
+          compiledName.unshift(this.makeCode('['));
+          compiledName.push(this.makeCode(']'));
+        } else if (ref8 = fragmentsToText(compiledName), indexOf.call(JS_FORBIDDEN, ref8) >= 0) {
           compiledName.unshift(this.makeCode('"'));
           compiledName.push(this.makeCode('"'));
         }
diff --git a/src/nodes.coffee b/src/nodes.coffee
index 680bb21f01..781a2bcfb7 100644
--- a/src/nodes.coffee
+++ b/src/nodes.coffee
@@ -981,27 +981,18 @@ exports.Obj = class Obj extends Base
     if @generated
       for node in props when node instanceof Value
         node.error 'cannot have an implicit value in an implicit object'
-    break for prop, dynamicIndex in props when (prop.variable or prop).base instanceof Parens
-    hasDynamic  = dynamicIndex < props.length
-    idt         = o.indent += TAB
-    lastNoncom  = @lastNonComment @properties
+    idt        = o.indent += TAB
+    lastNoncom = @lastNonComment @properties
     answer = []
-    if hasDynamic
-      oref = o.scope.freeVariable 'obj'
-      answer.push @makeCode "(\n#{idt}#{oref} = "
-    answer.push @makeCode "{#{if props.length is 0 or dynamicIndex is 0 then '}' else '\n'}"
+    answer.push @makeCode "{#{if props.length is 0 then '}' else '\n'}"
     for prop, i in props
-      if i is dynamicIndex
-        answer.push @makeCode "\n#{idt}}" unless i is 0
-        answer.push @makeCode ',\n'
-      join = if i is props.length - 1 or i is dynamicIndex - 1
+      join = if i is props.length - 1
         ''
       else if prop is lastNoncom or prop instanceof Comment
         '\n'
       else
         ',\n'
       indent = if prop instanceof Comment then '' else idt
-      indent += TAB if hasDynamic and i < dynamicIndex
       if prop instanceof Assign
         if prop.context isnt 'object'
           prop.operatorToken.error "unexpected #{prop.operatorToken.value}"
@@ -1009,26 +1000,18 @@ exports.Obj = class Obj extends Base
           prop.variable.error 'invalid object key'
       if prop instanceof Value and prop.this
         prop = new Assign prop.properties[0].name, prop, 'object'
-      if prop not instanceof Comment
-        if i < dynamicIndex
-          if prop not instanceof Assign
-            prop = new Assign prop, prop, 'object'
+      if prop not instanceof Comment and prop not instanceof Assign
+        if prop.isComplex()
+          [key, value] = prop.base.cache o
+          key  = new PropertyName key.value if key instanceof IdentifierLiteral
+          prop = new Assign key, value, 'object'
         else
-          if prop instanceof Assign
-            key = prop.variable
-            value = prop.value
-          else
-            [key, value] = prop.base.cache o
-            key = new PropertyName key.value if key instanceof IdentifierLiteral
-          prop = new Assign (new Value (new IdentifierLiteral oref), [new Access key]), value
+          prop = new Assign prop, prop, 'object'
       if indent then answer.push @makeCode indent
       answer.push prop.compileToFragments(o, LEVEL_TOP)...
       if join then answer.push @makeCode join
-    if hasDynamic
-      answer.push @makeCode ",\n#{idt}#{oref}\n#{@tab})"
-    else
-      answer.push @makeCode "\n#{@tab}}" unless props.length is 0
-    if @front and not hasDynamic then @wrapInBraces answer else answer
+    answer.push @makeCode "\n#{@tab}}" unless props.length is 0
+    if @front then @wrapInBraces answer else answer
 
   assigns: (name) ->
     for prop in @properties when prop.assigns name then return yes
@@ -1431,7 +1414,10 @@ exports.Assign = class Assign extends Base
     compiledName = @variable.compileToFragments o, LEVEL_LIST
 
     if @context is 'object'
-      if fragmentsToText(compiledName) in JS_FORBIDDEN
+      if @variable.isComplex()
+        compiledName.unshift @makeCode '['
+        compiledName.push @makeCode ']'
+      else if fragmentsToText(compiledName) in JS_FORBIDDEN
         compiledName.unshift @makeCode '"'
         compiledName.push @makeCode '"'
       return compiledName.concat @makeCode(": "), val