for let with when fix

Author: gkz

lib/ast.js

@@ -1698,7 +1698,7 @@ class exports.Fun extends Node
         if vr.isEmpty!
           vr = Var scope.temporary \arg
         else if vr.value is \..
-          vr = Var o.ref = scope.reference!
+          vr = Var o.ref = scope.temporary!
         else if vr not instanceof Var
           unaries = []
           while vr instanceof Unary
@@ -1977,7 +1977,7 @@ class exports.While extends Node
     for node in @body?.lines or [] then return node if node.getJump ctx
 
   addBody: (@body) ->
-    @body = Block If @guard, body if @guard
+    @body = Block If @guard, @body if @guard
     [top] = @body.lines
     @body.lines.length = 0 if top?verb is \continue and not top.label
     this
@@ -2080,11 +2080,24 @@ class exports.For extends While
       @item = Literal \.. if delete @ref
       body = Block Call.let do
         with []
-          ..push Assign Var(that), Literal \index if delete @index
-          ..push Assign that,      Literal \item if delete @item
+          ..push Assign Var(that), Literal \index$$ if @index
+          ..push Assign that,      Literal \item$$ if @item
         body
+
     super body
 
+    if @guard and @let and (@index or @item)
+      @body.lines[0].if.traverse-children !~>
+        if it instanceof Var
+          if @index and it.value is @index
+            it.value = \index$$
+          if @item and it.value is @item.value
+            it.value = \item$$
+    if @let
+      delete @index
+      delete @item
+    this
+
   compileNode: (o) ->
     o.loop = true
     temps = @temps = []
@@ -2141,8 +2154,8 @@ class exports.For extends While
     if @let
       @body.traverseChildren !->
         switch it.value
-        | \index => it.value = idx
-        | \item  => it.value = "#svar[#idx]"
+        | \index$$ => it.value = idx
+        | \item$$  => it.value = "#svar[#idx]"
     else
       @infuseIIFE!
     o.indent += TAB

src/ast.ls

@@ -594,8 +594,18 @@ for let k, v of {a: \b}
   ok true
 ok 7 is i is v
 
-fns = for <[foo bar]>
-  for let i in [7 8]
-    -> .. + i
-eq \foo7 fns.0.0!
-eq \bar8 fns.1.1!
+fns = for let <[foo bar]>
+  for let x in [6 7 8 9] when x % 2 == 0
+      -> .. + x
+eq \foo6 fns.0.0!
+eq \bar8 fns.1.1!
+
+xs = for let x, i in [1 to 10] by 2 when x % 3 == 0
+  -> i + x
+eq 5, xs[0]!
+eq 17, xs[1]!
+
+xs = for own let key, value of {a: 1, b: 2, c: 3, d: 4} when value % 2 == 0
+  -> key + value
+eq 'b2', xs[0]!
+eq 'd4', xs[1]!