diff --git a/moonscript/compile/format.lua b/moonscript/compile/format.lua
index c27d0dd..6dfc591 100644
--- a/moonscript/compile/format.lua
+++ b/moonscript/compile/format.lua
@@ -1,7 +1,6 @@
 module("moonscript.compile", package.seeall)
 local util = require("moonscript.util")
 local data = require("moonscript.data")
-local itwos = util.itwos
 local Set, ntype = data.Set, data.ntype
 local concat, insert = table.concat, table.insert
 indent_char = "  "
diff --git a/moonscript/compile/format.moon b/moonscript/compile/format.moon
index 5f1b1b1..a36d41e 100644
--- a/moonscript/compile/format.moon
+++ b/moonscript/compile/format.moon
@@ -3,7 +3,6 @@ module "moonscript.compile", package.seeall
 util = require "moonscript.util"
 data = require "moonscript.data"
 
-import itwos from util
 import Set, ntype from data
 import concat, insert from table
 
diff --git a/moonscript/compile/line.lua b/moonscript/compile/line.lua
index 9759e7f..20abd37 100644
--- a/moonscript/compile/line.lua
+++ b/moonscript/compile/line.lua
@@ -1,7 +1,6 @@
 module("moonscript.compile", package.seeall)
 local util = require("moonscript.util")
 local data = require("moonscript.data")
-local dump = require("moonscript.dump")
 require("moonscript.compile.format")
 require("moonscript.compile.types")
 local reversed = util.reversed
diff --git a/moonscript/compile/line.moon b/moonscript/compile/line.moon
index f2c819b..ac9920c 100644
--- a/moonscript/compile/line.moon
+++ b/moonscript/compile/line.moon
@@ -2,7 +2,6 @@ module "moonscript.compile", package.seeall
 
 util = require "moonscript.util"
 data = require "moonscript.data"
-dump = require "moonscript.dump"
 
 require "moonscript.compile.format"
 require "moonscript.compile.types"
diff --git a/moonscript/compile/value.lua b/moonscript/compile/value.lua
index 2303513..613eec8 100644
--- a/moonscript/compile/value.lua
+++ b/moonscript/compile/value.lua
@@ -1,7 +1,6 @@
 module("moonscript.compile", package.seeall)
 local util = require("moonscript.util")
 local data = require("moonscript.data")
-local dump = require("moonscript.dump")
 require("moonscript.compile.format")
 local ntype = data.ntype
 local concat, insert = table.concat, table.insert
diff --git a/moonscript/compile/value.moon b/moonscript/compile/value.moon
index 136192d..40530a1 100644
--- a/moonscript/compile/value.moon
+++ b/moonscript/compile/value.moon
@@ -3,7 +3,6 @@ module "moonscript.compile", package.seeall
 
 util = require "moonscript.util"
 data = require "moonscript.data"
-dump = require "moonscript.dump"
 
 require "moonscript.compile.format"
 
diff --git a/moonscript/data.lua b/moonscript/data.lua
index 1eb670f..e3b32b0 100644
--- a/moonscript/data.lua
+++ b/moonscript/data.lua
@@ -1,52 +1,87 @@
-
 module("moonscript.data", package.seeall)
-
-local stack_t = {}
-local _stack_mt = { __index = stack_t, __tostring = function(self)
-	return "<Stack {"..table.concat(self, ", ").."}>"
-end}
-
-function stack_t:pop()
-	return table.remove(self)
+local concat = table.concat
+ntype = function(node)
+  if type(node) ~= "table" then
+    return "value"
+  else
+    return node[1]
+  end
 end
-
-function stack_t:push(value)
-	table.insert(self, value)
-	return value
+Set = function(items)
+  local self = { }
+  do
+    local _item_0 = items
+    for _index_0 = 1, #_item_0 do
+      local key = _item_0[_index_0]
+      self[key] = true
+    end
+  end
+  return self
 end
-
-function stack_t:top()
-	return self[#self]
-end
-
-function Stack(...)
-	local self = setmetatable({}, _stack_mt)
-
-	for _, v in ipairs{...} do
-		self:push(v)
-	end
-
-	return self
-end
-
-function Set(items)
-	local self = {}
-	for _,item in ipairs(items) do
-		self[item] = true
-	end
-	return self
-end
-
--- find out the type of a node
-function ntype(node)
-	if type(node) ~= "table" then return "value" end
-	return node[1]
-end
-
-lua_keywords = Set{
-	'and', 'break', 'do', 'else', 'elseif',
-	'end', 'false', 'for', 'function', 'if',
-	'in', 'local', 'nil', 'not', 'or',
-	'repeat', 'return', 'then', 'true',
-	'until', 'while'
-}
+Stack = (function(_parent_0)
+  local _base_0 = {
+    __tostring = function(self)
+      return "<Stack {" .. concat(self, ", ") .. "}>"
+    end,
+    pop = function(self)
+      return table.remove(self)
+    end,
+    push = function(self, value)
+      table.insert(self, value)
+      return value
+    end,
+    top = function(self)
+      return self[#self]
+    end
+  }
+  _base_0.__index = _base_0
+  if _parent_0 then
+    setmetatable(_base_0, getmetatable(_parent_0).__index)
+  end
+  local _class_0 = setmetatable({
+    __init = function(self, ...)
+      do
+        local _item_0 = {
+          ...
+        }
+        for _index_0 = 1, #_item_0 do
+          local v = _item_0[_index_0]
+          self:push(v)
+        end
+      end
+      return nil
+    end
+  }, {
+    __index = _base_0,
+    __call = function(mt, ...)
+      local self = setmetatable({}, _base_0)
+      mt.__init(self, ...)
+      return self
+    end
+  })
+  _base_0.__class = _class_0
+  return _class_0
+end)()
+lua_keywords = Set({
+  'and',
+  'break',
+  'do',
+  'else',
+  'elseif',
+  'end',
+  'false',
+  'for',
+  'function',
+  'if',
+  'in',
+  'local',
+  'nil',
+  'not',
+  'or',
+  'repeat',
+  'return',
+  'then',
+  'true',
+  'until',
+  'while'
+})
diff --git a/moonscript/data.moon b/moonscript/data.moon
new file mode 100644
index 0000000..770e37b
--- /dev/null
+++ b/moonscript/data.moon
@@ -0,0 +1,47 @@
+-- data structure utils
+
+module "moonscript.data", package.seeall
+
+export Set, Stack
+export ntype, lua_keywords
+
+import concat from table
+
+-- type of node as string
+ntype = (node) ->
+  if type(node) != "table"
+    "value"
+  else
+    node[1]
+
+Set = (items) ->
+  self = {}
+  self[key] = true for key in *items
+  self
+
+class Stack
+  __tostring: => "<Stack {"..concat(self, ", ").."}>"
+
+  new: (...) =>
+    @push v for v in *{...}
+    nil
+
+  pop: =>
+    table.remove self
+
+  push: (value) =>
+    table.insert self, value
+    value
+
+  top: =>
+    self[#self]
+
+
+lua_keywords = Set{
+	'and', 'break', 'do', 'else', 'elseif',
+	'end', 'false', 'for', 'function', 'if',
+	'in', 'local', 'nil', 'not', 'or',
+	'repeat', 'return', 'then', 'true',
+	'until', 'while'
+}
+
diff --git a/moonscript/dump.lua b/moonscript/dump.lua
index c00bc32..780dea3 100644
--- a/moonscript/dump.lua
+++ b/moonscript/dump.lua
@@ -1,29 +1,46 @@
-
 module("moonscript.dump", package.seeall)
-
-local function flat_value(op, depth)
-	depth = depth or 1
-
-	if type(op) == "string" then return '"'..op..'"' end
-	if type(op) ~= "table" then return tostring(op) end
-	local items = {}
-	for _, item in ipairs(op) do
-		table.insert(items, flat_value(item, depth+1))
-	end
-
-	local pos = op[-1]
-
-	return "{"..(pos and "["..pos.."] " or "")..table.concat(items, ", ").."}"
+local flat_value
+flat_value = function(op, depth)
+  if depth == nil then
+    depth = 1
+  end
+  if type(op) == "string" then
+    return '"' .. op .. '"'
+  end
+  if type(op) ~= "table" then
+    return tostring(op)
+  end
+  local items = (function()
+    local _accum_0 = { }
+    local _len_0 = 0
+    do
+      local _item_0 = op
+      for _index_0 = 1, #_item_0 do
+        local item = _item_0[_index_0]
+        _len_0 = _len_0 + 1
+        _accum_0[_len_0] = flat_value(item, depth + 1)
+      end
+    end
+    return _accum_0
+  end)()
+  local pos = op[-1]
+  return "{" .. (pos and "[" .. pos .. "] " or "") .. table.concat(items, ", ") .. "}"
 end
-
-function value(op)
-	return flat_value(op)
+value = function(op)
+  return flat_value(op)
 end
-
-function tree(block, depth)
-	depth = depth or 0
-	for _, op in ipairs(block) do
-		print(flat_value(op))
-	end
+tree = function(block)
+  return (function()
+    local _accum_0 = { }
+    local _len_0 = 0
+    do
+      local _item_0 = block
+      for _index_0 = 1, #_item_0 do
+        local value = _item_0[_index_0]
+        _len_0 = _len_0 + 1
+        _accum_0[_len_0] = print(flat_value(value))
+      end
+    end
+    return _accum_0
+  end)()
 end
-
diff --git a/moonscript/dump.moon b/moonscript/dump.moon
new file mode 100644
index 0000000..077fc96
--- /dev/null
+++ b/moonscript/dump.moon
@@ -0,0 +1,19 @@
+
+module "moonscript.dump", package.seeall
+
+export value, tree
+
+flat_value = (op, depth=1) ->
+  return '"'..op..'"' if type(op) == "string"
+  return tostring(op) if type(op) != "table"
+
+  items = [flat_value item, depth + 1 for item in *op]
+  pos = op[-1]
+
+  "{"..(pos and "["..pos.."] " or "")..table.concat(items, ", ").."}"
+
+value = (op) ->
+  flat_value op
+
+tree = (block) ->
+  print flat_value value for value in *block
diff --git a/moonscript/util.lua b/moonscript/util.lua
index 15d9166..a1a9123 100644
--- a/moonscript/util.lua
+++ b/moonscript/util.lua
@@ -1,144 +1,101 @@
-
 module("moonscript.util", package.seeall)
-
+local concat = table.concat
 moon = {
-	is_object = function(value)
-		return type(value) == "table" and value.__class
-	end,
-	type = function(value)
-		base_type = type(value)
-		if base_type == "table" then
-			cls = value.__class
-			if cls then return cls end
-		end
-		return base_type
-	end
+  is_object = function(value)
+    return type(value) == "table" and value.__class
+  end,
+  type = function(value)
+    local base_type = type(value)
+    if base_type == "table" then
+      local cls = value.__class
+      if cls then
+        return cls
+      end
+    end
+    return base_type
+  end
 }
-
-function pos_to_line(str, pos)
-	local line = 1
-	for _ in str:sub(1, pos):gmatch("\n") do
-		line = line + 1
-	end
-	return line
+pos_to_line = function(str, pos)
+  local line = 1
+  for _ in str:sub(1, pos):gmatch("\n") do
+    line = line + 1
+  end
+  return line
 end
-
-function get_closest_line(str, line_num)
-	local line = get_line(str, line_num)
-	if (not line or trim(line) == "") and line_num > 1 then
-		return get_closest_line(str, line_num - 1)
-	end
-
-	return line, line_num
+get_closest_line = function(str, line_num)
+  local line = get_line(str, line_num)
+  if (not line or trim(line) == "") and line_num > 1 then
+    return get_closest_line(str, line_num - 1)
+  else
+    return line, line_num
+  end
 end
-
-function get_line(str, line_num)
-	for line in str:gmatch("(.-)[\n$]") do
-		if line_num == 1 then
-			return line
-		end
-		line_num = line_num - 1
-	end
+get_line = function(str, line_num)
+  for line in str:gmatch("(.-)[\n$]") do
+    if line_num == 1 then
+      return line
+    end
+    line_num = line_num - 1
+  end
 end
-
--- shallow copy
-function clone(tbl)
-	local out = {}
-	for k,v in pairs(tbl) do
-		out[k] = v
-	end
-	return out
+reversed = function(seq)
+  return coroutine.wrap(function()
+    for i = #seq, 1, -1 do
+      coroutine.yield(i, seq[i])
+    end
+  end)
 end
-
-function map(tbl, fn)
-	local out = {}
-	for i,v in ipairs(tbl) do
-		out[i] = fn(v)
-	end
-	return out
+trim = function(str)
+  return str:match("^%s*(.-)%s*$")
 end
-
-function every(tbl, fn)
-	for i=1,#tbl do
-		local pass
-		if fn then
-			pass = fn(tbl[i])
-		else
-			pass = tbl[i]
-		end
-
-		if not pass then return false end
-	end
-	return true
+split = function(str, delim)
+  if str == "" then
+    return { }
+  end
+  str = str .. delim
+  return (function()
+    local _accum_0 = { }
+    local _len_0 = 0
+    for m in str:gmatch("(.-)" .. delim) do
+      _len_0 = _len_0 + 1
+      _accum_0[_len_0] = m
+    end
+    return _accum_0
+  end)()
 end
-
-function bind(obj, name)
-	return function(...)
-		return obj[name](obj, ...)
-	end
+dump = function(what)
+  local seen = { }
+  local _dump
+  _dump = function(what, depth)
+    if depth == nil then
+      depth = 0
+    end
+    local t = type(what)
+    if t == "string" then
+      return '"' .. what .. '"\n'
+    elseif t == "table" then
+      if seen[what] then
+        return "recursion(" .. tostring(what) .. ")...\n"
+      end
+      local _ = seen[what] == true
+      depth = depth + 1
+      local lines = (function()
+        local _accum_0 = { }
+        local _len_0 = 0
+        for k, v in pairs(what) do
+          local _value_0 = (" "):rep(depth * 4) .. "[" .. tostring(k) .. "] = " .. _dump(v, depth)
+          if _value_0 ~= nil then
+            _len_0 = _len_0 + 1
+            _accum_0[_len_0] = _value_0
+          end
+        end
+        return _accum_0
+      end)()
+      seen[what] = false
+      return "{\n" .. concat(lines) .. (" "):rep((depth - 1) * 4) .. "}\n"
+    else
+      return tostring(what) .. "\n"
+    end
+  end
+  return _dump(what)
 end
-
-function itwos(seq)
-	n = 2
-	return coroutine.wrap(function()
-		for i = 1, #seq-n+1 do
-			coroutine.yield(i, seq[i], i+1, seq[i+1])
-		end
-	end)
-end
-
-function reversed(seq)
-	return coroutine.wrap(function()
-		for i=#seq,1,-1 do
-			coroutine.yield(i, seq[i])
-		end
-	end)
-end
-
-function dump(what)
-	local seen = {}
-	local function _dump(what, depth)
-		depth = depth or 0
-		local t = type(what)
-
-		if t == "string" then
-			return '"'..what..'"\n'
-		elseif t == "table" then
-			if seen[what] then 
-				return "recursion("..tostring(what)..")...\n"
-			end
-			seen[what] = true
-
-			depth = depth + 1
-			out = "{\n"
-			for k,v in pairs(what) do
-				out = out..(" "):rep(depth*4).."["..tostring(k).."] = ".._dump(v, depth)
-			end
-
-			seen[what] = false
-
-			return out .. (" "):rep((depth-1)*4) .. "}\n"
-		else
-			return tostring(what).."\n"
-		end
-	end
-
-	return _dump(what)
-end
-
-function split(str, delim)
-	if str == "" then return {} end
-	str = str..delim
-	local out = {}
-	for m in str:gmatch("(.-)"..delim) do
-		table.insert(out, m)
-	end
-	return out
-end
-
-
-function trim(str)
-	return str:match("^%s*(.-)%s*$")
-end
-
-
diff --git a/moonscript/util.moon b/moonscript/util.moon
new file mode 100644
index 0000000..d58c530
--- /dev/null
+++ b/moonscript/util.moon
@@ -0,0 +1,76 @@
+
+module "moonscript.util", package.seeall
+
+export moon
+export pos_to_line, get_closest_line, get_line
+export reversed, trim, split
+export dump
+
+import concat from table
+
+moon =
+  is_object: (value) -> -- is a moonscript object
+    type(value) == "table" and value.__class
+  type: (value) -> -- the moonscript object class
+    base_type = type value
+    if base_type == "table"
+      cls = value.__class
+      return cls if cls
+    base_type
+
+-- convet position in text to line number
+pos_to_line = (str, pos) ->
+  line = 1
+  for _ in str\sub(1, pos)\gmatch("\n")
+    line += 1
+  line
+
+get_closest_line = (str, line_num) ->
+  line = get_line str, line_num
+  if (not line or trim(line) == "") and line_num > 1
+    get_closest_line(str, line_num - 1)
+  else
+    line, line_num
+
+get_line = (str, line_num) ->
+  for line in str\gmatch "(.-)[\n$]"
+    return line if line_num == 1
+    line_num -= 1
+
+reversed = (seq) ->
+  coroutine.wrap ->
+    for i=#seq,1,-1
+      coroutine.yield i, seq[i]
+
+trim = (str) ->
+  str\match "^%s*(.-)%s*$"
+
+split = (str, delim) ->
+  return {} if str == ""
+  str ..= delim
+  [m for m in str\gmatch("(.-)"..delim)]
+
+dump = (what) ->
+  seen = {}
+  _dump = (what, depth=0) ->
+    t = type what
+    if t == "string"
+			'"'..what..'"\n'
+    elseif t == "table"
+      if seen[what]
+        return "recursion("..tostring(what) ..")...\n"
+      seen[what] == true
+
+      depth += 1
+      lines = for k,v in pairs what
+        (" ")\rep(depth*4).."["..tostring(k).."] = ".._dump(v, depth)
+
+      seen[what] = false
+
+      "{\n" .. concat(lines) .. (" ")\rep((depth - 1)*4) .. "}\n"
+    else
+      tostring(what).."\n"
+
+  _dump what
+
+