A little refactoring. Add a new function to get all symbols in a destructuring.

lib/ast.js

@@ -445,15 +445,13 @@ var AST_Lambda = DEFNODE("Lambda", "name argnames uses_arguments", {
     },
     args_as_names: function () {
         var out = [];
-        this.walk(new TreeWalker(function (parm) {
-            var that = this;
-            if (parm instanceof AST_SymbolFunarg) {
-                out.push(parm);
+        for (var i = 0; i < this.argnames.length; i++) {
+            if (this.argnames[i] instanceof AST_Destructuring) {
+                out = out.concat(this.argnames[i].all_symbols());
+            } else {
+                out.push(this.argnames[i]);
             }
-            if (parm instanceof AST_Expansion) {
-                out.push(parm.symbol);
-            }
-        }));
+        }
         return out;
     },
     _walk: function(visitor) {
@@ -492,6 +490,18 @@ var AST_Destructuring = DEFNODE("Destructuring", "names is_array", {
                 name._walk(visitor);
             });
         });
+    },
+    all_symbols: function() {
+        var out = [];
+        this.walk(new TreeWalker(function (node) {
+            if (node instanceof AST_Symbol) {
+                out.push(node);
+            }
+            if (node instanceof AST_Expansion) {
+                out.push(node.symbol);
+            }
+        }));
+        return out;
     }
 });