don't let unpack names reuse ones in scope, fixes #211, fixes #256

moonscript/transform/names.lua

@@ -101,7 +101,18 @@ do
   _base_0.__class = _class_0
   NameProxy = _class_0
 end
+local is_name_proxy
+is_name_proxy = function(v)
+  if not (type(v) == "table") then
+    return false
+  end
+  local _exp_0 = v.__class
+  if LocalName == _exp_0 or NameProxy == _exp_0 then
+    return true
+  end
+end
 return {
   NameProxy = NameProxy,
-  LocalName = LocalName
+  LocalName = LocalName,
+  is_name_proxy = is_name_proxy
 }

moonscript/transform/names.moon

@@ -41,5 +41,11 @@ class NameProxy
     else
       ("name<prefix(%s)>")\format @prefix
 
+is_name_proxy = (v) ->
+  return false unless type(v) == "table"
 
-{ :NameProxy, :LocalName }
+  switch v.__class
+    when LocalName, NameProxy
+      true
+
+{ :NameProxy, :LocalName, :is_name_proxy }

moonscript/transform/statement.lua

@@ -1,7 +1,10 @@
 local Transformer
 Transformer = require("moonscript.transform.transformer").Transformer
-local NameProxy
+local NameProxy, LocalName, is_name_proxy
-NameProxy = require("moonscript.transform.names").NameProxy
+do
+  local _obj_0 = require("moonscript.transform.names")
+  NameProxy, LocalName, is_name_proxy = _obj_0.NameProxy, _obj_0.LocalName, _obj_0.is_name_proxy
+end
 local Run, transform_last_stm, implicitly_return, last_stm
 do
   local _obj_0 = require("moonscript.transform.statements")
@@ -649,6 +652,18 @@ return Transformer({
           }
         }
       end
+      local names
+      do
+        local _accum_0 = { }
+        local _len_0 = 1
+        local _list_0 = node.names
+        for _index_0 = 1, #_list_0 do
+          local n = _list_0[_index_0]
+          _accum_0[_len_0] = is_name_proxy(n) and n or LocalName(n) or n
+          _len_0 = _len_0 + 1
+        end
+        names = _accum_0
+      end
       return build.group({
         list_name ~= list and build.assign_one(list_name, list) or NOOP,
         slice_var or NOOP,
@@ -658,7 +673,7 @@ return Transformer({
           body = {
             {
               "assign",
-              node.names,
+              names,
               {
                 NameProxy.index(list_name, index_name)
               }

moonscript/transform/statement.moon

@@ -1,6 +1,6 @@
 import Transformer from require "moonscript.transform.transformer"
 
-import NameProxy from require "moonscript.transform.names"
+import NameProxy, LocalName, is_name_proxy from require "moonscript.transform.names"
 
 import Run, transform_last_stm, implicitly_return, last_stm
   from require "moonscript.transform.statements"
@@ -400,6 +400,8 @@ Transformer {
       else
         {1, {"length", list_name}}
 
+      names = [is_name_proxy(n) and n or LocalName(n) or n for n in *node.names]
+
       return build.group {
         list_name != list and build.assign_one(list_name, list) or NOOP
         slice_var or NOOP
@@ -407,7 +409,7 @@ Transformer {
           name: index_name
           bounds: bounds
           body: {
-            {"assign", node.names, { NameProxy.index list_name, index_name }}
+            {"assign", names, { NameProxy.index list_name, index_name }}
             build.group node.body
           }
         }