Revert "Revert "revert underscore""

This reverts commit 143eb425.

forbid/underscore.lua

@@ -37,11 +37,12 @@ end
 
 function Underscore.iter(list_or_iter)
 	if type(list_or_iter) == "function" then return list_or_iter end
-	local i = 0
-	return function()
-		i = i + 1
-		return list_or_iter[i]
-	end
+	
+	return coroutine.wrap(function() 
+		for i=1,#list_or_iter do
+			coroutine.yield(list_or_iter[i])
+		end
+	end)
 end
 
 function Underscore.range(start_i, end_i, step)
@@ -50,11 +51,11 @@ function Underscore.range(start_i, end_i, step)
 		start_i = 1
 	end
 	step = step or 1
-	local list = {}
-	for i=start_i, end_i, step do
-		table.insert(list,i)
-	end
-	local range_iter = Underscore.iter(list)
+	local range_iter = coroutine.wrap(function() 
+		for i=start_i, end_i, step do
+			coroutine.yield(i)
+		end
+	end)
 	return Underscore:new(range_iter)
 end