Lots of optimizations and simplifications, especially towards getting

better performance on luajit.

12 files changed, 189 insertions, 291 deletions

diff --git a/code_obj.lua b/code_obj.lua
index 47e08cb..39f6c95 100644
--- a/code_obj.lua
+++ b/code_obj.lua
@@ -187,7 +187,7 @@ do
       for _index_0 = 1, #vars do
         local var = vars[_index_0]
         assert(var.type == "Var")
-        removals[var.value] = true
+        removals[var[1]] = true
       end
       local stack = {
         self
@@ -196,7 +196,7 @@ do
         local lua
         lua, stack[#stack] = stack[#stack], nil
         for i = #lua.free_vars, 1, -1 do
-          if removals[lua.free_vars[i].value] then
+          if removals[lua.free_vars[i][1]] then
             remove(lua.free_vars, i)
           end
         end
@@ -264,7 +264,7 @@ do
           local _len_0 = 1
           for _index_0 = 1, #to_declare do
             local v = to_declare[_index_0]
-            _accum_0[_len_0] = string.as_lua_id(v.value)
+            _accum_0[_len_0] = string.as_lua_id(v[1])
             _len_0 = _len_0 + 1
           end
           return _accum_0
diff --git a/code_obj.moon b/code_obj.moon
index 45df615..dae3f52 100644
--- a/code_obj.moon
+++ b/code_obj.moon
@@ -109,13 +109,13 @@ class Lua extends Code
         removals = {}
         for var in *vars
             assert(var.type == "Var")
-            removals[var.value] = true
+            removals[var[1]] = true
         
         stack = {self}
         while #stack > 0
             lua, stack[#stack] = stack[#stack], nil
             for i=#lua.free_vars,1,-1
-                if removals[lua.free_vars[i].value]
+                if removals[lua.free_vars[i][1]]
                     remove lua.free_vars, i
             for b in *lua.bits
                 if type(b) != 'string'
@@ -147,7 +147,7 @@ class Lua extends Code
             gather_from self
         if #to_declare > 0
             @remove_free_vars to_declare
-            @prepend "local #{concat [string.as_lua_id(v.value) for v in *to_declare], ", "};\n"
+            @prepend "local #{concat [string.as_lua_id(v[1]) for v in *to_declare], ", "};\n"
         return to_declare
 
     __tostring: =>
diff --git a/compile_lib.sh b/compile_lib.sh
index fa932b3..d7df5f8 100755
--- a/compile_lib.sh
+++ b/compile_lib.sh
@@ -6,11 +6,11 @@ moonc *.moon
 rm -f core/*.lua lib/*.lua
 for file in core/*.nom; do
     printf "Compiling $file ..."
-    lua ./nomsu.lua -O -o "core/$(basename $file .nom).lua" $file
+    luajit ./nomsu.lua -O -o "core/$(basename $file .nom).lua" $file
     echo "done."
 done
 for file in lib/*.nom; do
     printf "Compiling $file ..."
-    lua ./nomsu.lua -O -o "lib/$(basename $file .nom).lua" $file
+    luajit ./nomsu.lua -O -o "lib/$(basename $file .nom).lua" $file
     echo "done."
 done
diff --git a/core/control_flow.nom b/core/control_flow.nom
index 73a0f43..f0238a4 100644
--- a/core/control_flow.nom
+++ b/core/control_flow.nom
@@ -188,14 +188,14 @@ immediately
             %body has subtree % where
                 (%.type = "Action") and
                     (%.stub is "do next %") and
-                        %.3.value = %var.value
+                        %.3.(1) = %var.(1)
         ..: to %lua write (Lua "\n    ::continue_\(%var as lua identifier)::")
         to %lua write "\nend --foreach-loop"
         if
             %body has subtree % where
                 (%.type = "Action") and
                     (%.stub is "stop %") and
-                        %.2.value = %var.value
+                        %.2.(1) = %var.(1)
         ..
             %lua <-
                 Lua ".."
@@ -222,14 +222,14 @@ immediately
             %body has subtree % where
                 (%.type = "Action") and
                     (%.stub is "do next %") and
-                        %.3.value = %key.value
+                        %.3.(1) = %key.(1)
         ..: to %lua write (Lua "\n    ::continue_\(%key as lua identifier)::")
 
         if
             %body has subtree % where
                 (%.type = "Action") and
                     (%.stub is "do next %") and
-                        %.3.value = %value.value
+                        %.3.(1) = %value.(1)
         ..: to %lua write (Lua "\n    ::continue_\(%value as lua identifier)::")
         to %lua write "\nend --foreach-loop"
         
@@ -238,14 +238,14 @@ immediately
             %body has subtree % where
                 (%.type = "Action") and
                     (%.stub is "stop %") and
-                        %.2.value = %key.value
+                        %.2.(1) = %key.(1)
         ..: to %stop_labels write "\n::stop_\(%key as lua identifier)::"
 
         if
             %body has subtree % where
                 (%.type = "Action") and
                     (%.stub is "stop %") and
-                        %.2.value = %value.value
+                        %.2.(1) = %value.(1)
         ..: to %stop_labels write "\n::stop_\(%value as lua identifier)::"
 
         if: (length of %stop_labels) > 0
diff --git a/core/metaprogramming.nom b/core/metaprogramming.nom
index ec65f3e..e413191 100644
--- a/core/metaprogramming.nom
+++ b/core/metaprogramming.nom
@@ -82,7 +82,7 @@ immediately
             for i,tok in ipairs(\%shorthand[1]) do
                 if tok.type == "Var" then
                     local lua_var = tostring(nomsu:tree_to_lua(tok))
-                    replacements[tok.value] = lua_var
+                    replacements[tok[1]] = lua_var
                     lua:append(", ", lua_var)
                 end
             end
@@ -90,12 +90,10 @@ immediately
             local function make_tree(t)
                 if type(t) ~= 'table' and type(t) ~= 'userdata' then
                     return repr(t)
-                elseif t.type == 'Var' and replacements[t.value] then
-                    return replacements[t.value]
+                elseif t.type == 'Var' and replacements[t[1]] then
+                    return replacements[t[1]]
                 elseif t.type == 'Var' then
-                    return t.type.."("..repr(tostring(t.source))..", "..repr(t.value.."#"..tostring(MANGLE_INDEX))..")"
-                elseif t.value then
-                    return t.type.."("..repr(tostring(t.source))..", "..repr(t.value)..")"
+                    return t.type.."("..repr(tostring(t.source))..", "..repr(t[1].."#"..tostring(MANGLE_INDEX))..")"
                 else
                     local bits = {repr(tostring(t.source))}
                     for i, entry in ipairs(t) do
diff --git a/core/operators.nom b/core/operators.nom
index 4ec8ff1..555a636 100644
--- a/core/operators.nom
+++ b/core/operators.nom
@@ -160,8 +160,7 @@ immediately
     # Unary operators
     compile [- %] to: Lua value "(- \(% as lua expr))"
     compile [not %] to: Lua value "(not \(% as lua expr))"
-    # Using custom "len()" instead of Lua's "#" operator for compatibility with luajit.
-    compile [length of %list] to: Lua value "len(\(%list as lua expr))"
+    compile [length of %list] to: Lua value "(#\(%list as lua expr))"
 
 # Update operators
 immediately
diff --git a/nomsu.lua b/nomsu.lua
index e9d394f..4f61c29 100644
--- a/nomsu.lua
+++ b/nomsu.lua
@@ -1,33 +1,10 @@
 local _pairs, _ipairs = pairs, ipairs
 if jit then
   package.cpath = "./luajit_lpeg/?.so;" .. package.cpath
-  lpeg = require('lpeg')
+  package.path = "./luajit_lpeg/?.lua;" .. package.path
   bit32 = require('bit')
-  pairs = function(x)
-    do
-      local mt = getmetatable(x)
-      if mt then
-        if mt.__pairs then
-          return mt.__pairs(x)
-        end
-      end
-    end
-    return _pairs(x)
-  end
-  ipairs = function(x)
-    do
-      local mt = getmetatable(x)
-      if mt then
-        if mt.__ipairs then
-          return mt.__ipairs(x)
-        end
-      end
-    end
-    return _ipairs(x)
-  end
-else
-  lpeg = require('lpeg')
 end
+lpeg = require('lpeg')
 re = require('re')
 lpeg.setmaxstack(10000)
 local P, R, V, S, Cg, C, Cp, B, Cmt, Carg
@@ -53,6 +30,11 @@ do
   local _obj_0 = table
   insert, remove, concat = _obj_0.insert, _obj_0.remove, _obj_0.concat
 end
+local match, sub, rep, gsub, format, byte
+do
+  local _obj_0 = string
+  match, sub, rep, gsub, format, byte, match = _obj_0.match, _obj_0.sub, _obj_0.rep, _obj_0.gsub, _obj_0.format, _obj_0.byte, _obj_0.match
+end
 local debug_getinfo = debug.getinfo
 local Nomsu, Lua, Source
 do
@@ -61,11 +43,11 @@ do
 end
 local STDIN, STDOUT, STDERR = "/dev/fd/0", "/dev/fd/1", "/dev/fd/2"
 string.as_lua_id = function(str)
-  return "_" .. (str:gsub("%W", function(c)
+  return "_" .. (gsub(str, "%W", function(c)
     if c == "_" then
       return "__"
     else
-      return ("_%x"):format(c:byte())
+      return format("_%x", byte(c))
     end
   end))
 end
@@ -91,10 +73,13 @@ iterate_single = function(item, prev)
 end
 local all_files
 all_files = function(path)
-  if path:match("%.nom$") or path:match("%.lua$") or path:match("^/dev/fd/[012]$") then
+  if match(path, "%.nom$") or match(path, "%.lua$") or match(path, "^/dev/fd/[012]$") then
     return iterate_single, path
   end
-  path = path:gsub("\\", "\\\\"):gsub("`", ""):gsub('"', '\\"'):gsub("$", "")
+  path = gsub(path, "\\", "\\\\")
+  path = gsub(path, "`", "")
+  path = gsub(path, '"', '\\"')
+  path = gsub(path, "$", "")
   return coroutine.wrap(function()
     local f = io.popen('find -L "' .. path .. '" -not -path "*/\\.*" -type f -name "*.nom"')
     for line in f:lines() do
@@ -153,9 +138,9 @@ do
       return ret
     end
     if type(i) == 'number' then
-      return string.sub(self, i, i)
+      return sub(self, i, i)
     elseif type(i) == 'table' then
-      return string.sub(self, i[1], i[2])
+      return sub(self, i[1], i[2])
     end
   end
 end
@@ -187,19 +172,19 @@ do
   _with_0.utf8_char = (R("\194\223") * R("\128\191") + R("\224\239") * R("\128\191") * R("\128\191") + R("\240\244") * R("\128\191") * R("\128\191") * R("\128\191"))
   _with_0.ident_char = R("az", "AZ", "09") + P("_") + _with_0.utf8_char
   _with_0.indent = Cmt(Carg(1), function(self, start, userdata)
-    if #self:match("^[ ]*", start) >= userdata.indent + 4 then
+    if #match(self, "^[ ]*", start) >= userdata.indent + 4 then
       userdata.indent = userdata.indent + 4
       return start + userdata.indent
     end
   end)
   _with_0.dedent = Cmt(Carg(1), function(self, start, userdata)
-    if #self:match("^[ ]*", start) <= userdata.indent - 4 then
+    if #match(self, "^[ ]*", start) <= userdata.indent - 4 then
       userdata.indent = userdata.indent - 4
       return start
     end
   end)
   _with_0.nodent = Cmt(Carg(1), function(self, start, userdata)
-    if #self:match("^[ ]*", start) >= userdata.indent then
+    if #match(self, "^[ ]*", start) >= userdata.indent then
       return start + userdata.indent
     end
   end)
@@ -403,12 +388,12 @@ do
             end
           end
           insert(_running_files, filename)
-          if filename:match("%.lua$") then
+          if match(filename, "%.lua$") then
             local file = assert(FILE_CACHE[filename], "Could not find file: " .. tostring(filename))
             ret = self:run_lua(Lua(Source(filename, 1, #file), file))
-          elseif filename:match("%.nom$") or filename:match("^/dev/fd/[012]$") then
+          elseif match(filename, "%.nom$") or match(filename, "^/dev/fd/[012]$") then
             if not self.skip_precompiled then
-              local lua_filename = filename:gsub("%.nom$", ".lua")
+              local lua_filename = gsub(filename, "%.nom$", ".lua")
               local file = FILE_CACHE[lua_filename]
               if file then
                 ret = self:run_lua(Lua(Source(filename, 1, #file), file))
@@ -439,7 +424,7 @@ do
     run_lua = function(self, lua)
       assert(type(lua) ~= 'string', "Attempt to run lua string instead of Lua (object)")
       local lua_string = tostring(lua)
-      local run_lua_fn, err = load(lua_string, nil and tostring(lua.source), "t", self.environment)
+      local run_lua_fn, err = load(lua_string, tostring(lua.source), "t", self.environment)
       if not run_lua_fn then
         local n = 1
         local fn
@@ -590,22 +575,18 @@ do
           if not (AST.is_syntax_tree(t)) then
             return repr(t)
           end
-          if t.value then
-            return t.type .. "(" .. repr(tostring(t.source)) .. ", " .. repr(t.value) .. ")"
-          else
-            local bits
-            do
-              local _accum_0 = { }
-              local _len_0 = 1
-              for _index_0 = 1, #t do
-                local bit = t[_index_0]
-                _accum_0[_len_0] = make_tree(bit)
-                _len_0 = _len_0 + 1
-              end
-              bits = _accum_0
+          local bits
+          do
+            local _accum_0 = { }
+            local _len_0 = 1
+            for _index_0 = 1, #t do
+              local bit = t[_index_0]
+              _accum_0[_len_0] = make_tree(bit)
+              _len_0 = _len_0 + 1
             end
-            return t.type .. "(" .. repr(tostring(t.source)) .. ", " .. table.concat(bits, ", ") .. ")"
+            bits = _accum_0
           end
+          return t.type .. "(" .. repr(tostring(t.source)) .. ", " .. table.concat(bits, ", ") .. ")"
         end
         return Lua.Value(tree.source, make_tree(tree[1]))
       elseif "Block" == _exp_0 then
@@ -638,7 +619,7 @@ do
             end
             local bit_lua = self:tree_to_lua(bit)
             if not (bit_lua.is_value) then
-              local src = '    ' .. tostring(self:tree_to_nomsu(bit)):gsub('\n', '\n    ')
+              local src = '    ' .. gsub(tostring(self:tree_to_nomsu(bit)), '\n', '\n    ')
               local line = tostring(bit.source.filename) .. ":" .. tostring(pos_to_line(FILE_CACHE[bit.source.filename], bit.source.start))
               compile_error(bit, "Cannot use:\n%s\nas a string interpolation value, since it's not an expression.")
             end
@@ -675,8 +656,8 @@ do
           end
           lua:append(item_lua)
           local item_string = tostring(item_lua)
-          local last_line = item_string:match("[^\n]*$")
-          if item_string:match("\n") then
+          local last_line = match(item_string, "[^\n]*$")
+          if match(item_string, "\n") then
             line_length = #last_line
           else
             line_length = line_length + #last_line
@@ -700,7 +681,7 @@ do
           local entry_lua = self:tree_to_lua(entry)
           lua:append(entry_lua)
           local entry_lua_str = tostring(entry_lua)
-          local last_line = entry_lua_str:match("\n([^\n]*)$")
+          local last_line = match(entry_lua_str, "\n([^\n]*)$")
           if last_line then
             line_length = #last_line
           else
@@ -728,10 +709,10 @@ do
         if not (value_lua.is_value) then
           compile_error(tree[2], "Cannot use:\n%s\nas a dict value, since it's not an expression.")
         end
-        local key_str = tostring(key_lua):match([=[["']([a-zA-Z_][a-zA-Z0-9_]*)['"]]=])
+        local key_str = match(tostring(key_lua), [=[["']([a-zA-Z_][a-zA-Z0-9_]*)['"]]=])
         if key_str then
           return Lua(tree.source, key_str, "=", value_lua)
-        elseif tostring(key_lua):sub(1, 1) == "[" then
+        elseif sub(tostring(key_lua), 1, 1) == "[" then
           return Lua(tree.source, "[ ", key_lua, "]=", value_lua)
         else
           return Lua(tree.source, "[", key_lua, "]=", value_lua)
@@ -741,7 +722,7 @@ do
         if not (lua.is_value) then
           compile_error(tree[1], "Cannot index:\n%s\nsince it's not an expression.")
         end
-        local first_char = tostring(lua):sub(1, 1)
+        local first_char = sub(tostring(lua), 1, 1)
         if first_char == "{" or first_char == '"' or first_char == "[" then
           lua:parenthesize()
         end
@@ -753,10 +734,10 @@ do
           end
           local key_lua_str = tostring(key_lua)
           do
-            local lua_id = key_lua_str:match("^['\"]([a-zA-Z_][a-zA-Z0-9_]*)['\"]$")
+            local lua_id = match(key_lua_str, "^['\"]([a-zA-Z_][a-zA-Z0-9_]*)['\"]$")
             if lua_id then
               lua:append("." .. tostring(lua_id))
-            elseif key_lua_str:sub(1, 1) == '[' then
+            elseif sub(key_lua_str, 1, 1) == '[' then
               lua:append("[ ", key_lua, " ]")
             else
               lua:append("[", key_lua, "]")
@@ -765,9 +746,9 @@ do
         end
         return lua
       elseif "Number" == _exp_0 then
-        return Lua.Value(tree.source, tostring(tree.value))
+        return Lua.Value(tree.source, tostring(tree[1]))
       elseif "Var" == _exp_0 then
-        return Lua.Value(tree.source, string.as_lua_id(tree.value))
+        return Lua.Value(tree.source, string.as_lua_id(tree[1]))
       else
         return error("Unknown type: " .. tostring(tree.type))
       end
@@ -824,7 +805,7 @@ do
               if arg_nomsu and #arg_nomsu < MAX_LINE then
                 if bit.type == "Action" then
                   if can_use_colon and i > 1 then
-                    nomsu:append(next_space:match("[^ ]*"), ": ", arg_nomsu)
+                    nomsu:append(match(next_space, "[^ ]*"), ": ", arg_nomsu)
                     next_space = "\n.."
                     last_colon = i
                   else
@@ -853,7 +834,7 @@ do
                 nomsu:append(next_space, arg_nomsu)
                 next_space = "\n.."
               end
-              if next_space == " " and #(tostring(nomsu):match("[^\n]*$")) > MAX_LINE then
+              if next_space == " " and #(match(tostring(nomsu), "[^\n]*$")) > MAX_LINE then
                 next_space = "\n.."
               end
             end
@@ -888,7 +869,7 @@ do
           nomsu:append(line)
           if i < #tree then
             nomsu:append("\n")
-            if tostring(line):match("\n") then
+            if match(tostring(line), "\n") then
               nomsu:append("\n")
             end
           end
@@ -900,7 +881,7 @@ do
           for _index_0 = 1, #tree do
             local bit = tree[_index_0]
             if type(bit) == 'string' then
-              nomsu:append((bit:gsub("\\", "\\\\"):gsub("\n", "\\n")))
+              nomsu:append((gsub(gsub(bit, "\\", "\\\\"), "\n", "\\n")))
             else
               local interp_nomsu = self:tree_to_nomsu(bit, true)
               if interp_nomsu then
@@ -923,7 +904,7 @@ do
           local nomsu = Nomsu(tree.source, '".."\n    ')
           for i, bit in ipairs(self) do
             if type(bit) == 'string' then
-              nomsu:append((bit:gsub("\\", "\\\\"):gsub("\n", "\n    ")))
+              nomsu:append((gsub(gsub(bit, "\\", "\\\\"), "\n", "\\n")))
             else
               local interp_nomsu = self:tree_to_nomsu(bit, true)
               if interp_nomsu then
@@ -1085,9 +1066,9 @@ do
         end
         return nomsu
       elseif "Number" == _exp_0 then
-        return Nomsu(tree.source, tostring(tree.value))
+        return Nomsu(tree.source, tostring(tree[1]))
       elseif "Var" == _exp_0 then
-        return Nomsu(tree.source, "%", tree.value)
+        return Nomsu(tree.source, "%", tree[1])
       else
         return error("Unknown type: " .. tostring(tree.type))
       end
@@ -1268,60 +1249,11 @@ do
         math = math,
         io = io,
         load = load,
+        pairs = pairs,
+        ipairs = ipairs,
         list = list,
         dict = dict
       }
-      if jit then
-        self.environment.len = function(x)
-          do
-            local mt = getmetatable(x)
-            if mt then
-              if mt.__len then
-                return mt.__len(x)
-              end
-            end
-          end
-          return #x
-        end
-      else
-        self.environment.len = (function(x)
-          return #x
-        end)
-      end
-      self.environment.ipairs = function(x)
-        if type(x) == 'function' then
-          return coroutine.wrap(x)
-        elseif type(x) == 'thread' then
-          return coroutine.resume, x, nil
-        else
-          do
-            local mt = getmetatable(x)
-            if mt then
-              if mt.__ipairs then
-                return mt.__ipairs(x)
-              end
-            end
-          end
-        end
-        return _ipairs(x)
-      end
-      self.environment.pairs = function(x)
-        if type(x) == 'function' then
-          return coroutine.wrap(x)
-        elseif type(x) == 'thread' then
-          return coroutine.resume, x, nil
-        else
-          do
-            local mt = getmetatable(x)
-            if mt then
-              if mt.__pairs then
-                return mt.__pairs(x)
-              end
-            end
-          end
-        end
-        return _pairs(x)
-      end
       for k, v in pairs(AST) do
         self.environment[k] = v
       end
diff --git a/nomsu.moon b/nomsu.moon
index bef479b..5aaf683 100755
--- a/nomsu.moon
+++ b/nomsu.moon
@@ -14,27 +14,12 @@ export lpeg, re
 _pairs, _ipairs = pairs, ipairs
 if jit
     package.cpath = "./luajit_lpeg/?.so;"..package.cpath
-    --package.path = "./LPegLJ/src/?.lua;"..package.path
-    --lpeg = require "lpeglj"
-    lpeg = require 'lpeg'
+    package.path = "./luajit_lpeg/?.lua;"..package.path
     
     export bit32
     bit32 = require('bit')
 
-    export pairs, ipairs
-    pairs = (x)->
-        if mt = getmetatable(x)
-            if mt.__pairs
-                return mt.__pairs(x)
-        return _pairs(x)
-    ipairs = (x)->
-        if mt = getmetatable(x)
-            if mt.__ipairs
-                return mt.__ipairs(x)
-        return _ipairs(x)
-else
-    lpeg = require 'lpeg'
-
+lpeg = require 'lpeg'
 re = require 're'
 lpeg.setmaxstack 10000
 {:P,:R,:V,:S,:Cg,:C,:Cp,:B,:Cmt,:Carg} = lpeg
@@ -45,12 +30,13 @@ colors = setmetatable({}, {__index:->""})
 export colored
 colored = setmetatable({}, {__index:(_,color)-> ((msg)-> colors[color]..tostring(msg or '')..colors.reset)})
 {:insert, :remove, :concat} = table
+{:match, :sub, :rep, :gsub, :format, :byte, :match} = string
 debug_getinfo = debug.getinfo
 {:Nomsu, :Lua, :Source} = require "code_obj"
 STDIN, STDOUT, STDERR = "/dev/fd/0", "/dev/fd/1", "/dev/fd/2"
 
 string.as_lua_id = (str)->
-    "_"..(str\gsub("%W", (c)-> if c == "_" then "__" else ("_%x")\format(c\byte!)))
+    "_"..(gsub(str, "%W", (c)-> if c == "_" then "__" else format("_%x", byte(c))))
 
 -- TODO:
 -- consider non-linear codegen, rather than doing thunks for things like comprehensions
@@ -77,10 +63,13 @@ FILE_CACHE = setmetatable {}, {
 iterate_single = (item, prev) -> if item == prev then nil else item
 all_files = (path)->
     -- Sanitize path
-    if path\match("%.nom$") or path\match("%.lua$") or path\match("^/dev/fd/[012]$")
+    if match(path, "%.nom$") or match(path, "%.lua$") or match(path, "^/dev/fd/[012]$")
         return iterate_single, path
     -- TODO: improve sanitization
-    path = path\gsub("\\","\\\\")\gsub("`","")\gsub('"','\\"')\gsub("$","")
+    path = gsub(path,"\\","\\\\")
+    path = gsub(path,"`","")
+    path = gsub(path,'"','\\"')
+    path = gsub(path,"$","")
     return coroutine.wrap ->
         f = io.popen('find -L "'..path..'" -not -path "*/\\.*" -type f -name "*.nom"')
         for line in f\lines!
@@ -128,8 +117,8 @@ do
     STRING_METATABLE.__index = (i)=>
         ret = string[i]
         if ret != nil then return ret
-        if type(i) == 'number' then return string.sub(@, i, i)
-        elseif type(i) == 'table' then return string.sub(@, i[1], i[2])
+        if type(i) == 'number' then return sub(@, i, i)
+        elseif type(i) == 'table' then return sub(@, i[1], i[2])
 
 AST = require "nomsu_tree"
 
@@ -153,19 +142,19 @@ NOMSU_DEFS = with {}
     -- If the line begins with #indent+4 spaces, the pattern matches *those* spaces
     -- and adds them to the stack (not any more).
     .indent = Cmt Carg(1), (start, userdata)=>
-        if #@match("^[ ]*", start) >= userdata.indent + 4
+        if #match(@, "^[ ]*", start) >= userdata.indent + 4
             userdata.indent += 4
             return start + userdata.indent
     -- If the number of leading space characters is <= the number of space on the top of the
     -- stack minus 4, this pattern matches and pops off the top of the stack exactly once.
     .dedent = Cmt Carg(1), (start, userdata)=>
-        if #@match("^[ ]*", start) <= userdata.indent - 4
+        if #match(@, "^[ ]*", start) <= userdata.indent - 4
             userdata.indent -= 4
             return start
     -- If the number of leading space characters is >= the number on the top of the
     -- stack, this pattern matches and does not modify the stack.
     .nodent = Cmt Carg(1), (start, userdata)=>
-        if #@match("^[ ]*", start) >= userdata.indent
+        if #match(@, "^[ ]*", start) >= userdata.indent
             return start + userdata.indent
 
     .userdata = Carg(1)
@@ -178,8 +167,6 @@ NOMSU_DEFS = with {}
             seen_errors[start_pos+1] = colored.bright colored.yellow colored.onred "Too many errors, canceling parsing..."
             return #src+1
         err_pos = start_pos
-        --if src\sub(err_pos,err_pos)\match("[\r\n]")
-        --    err_pos += #src\match("[ \t\n\r]*", err_pos)
         line_no = pos_to_line(src, err_pos)
         src = FILE_CACHE[userdata.source.filename]
         line_starts = LINE_STARTS[src]
@@ -276,34 +263,10 @@ class NomsuCompiler
             :error, :package, :os, :require, :tonumber, :tostring, :string, :xpcall, :module,
             :print, :loadfile, :rawset, :_VERSION, :collectgarbage, :rawget, :bit32, :rawlen,
             :table, :assert, :dofile, :loadstring, :type, :select, :debug, :math, :io, :load,
+            :pairs, :ipairs,
             -- Nomsu types:
             :list, :dict,
         }
-        @environment.len = if jit
-            (x)->
-                if mt = getmetatable(x)
-                    if mt.__len
-                        return mt.__len(x)
-                return #x
-        else ((x) -> #x)
-        @environment.ipairs = (x)->
-            if type(x) == 'function'
-                return coroutine.wrap(x)
-            elseif type(x) == 'thread'
-                return coroutine.resume, x, nil
-            elseif mt = getmetatable(x)
-                if mt.__ipairs
-                    return mt.__ipairs(x)
-            return _ipairs(x)
-        @environment.pairs = (x)->
-            if type(x) == 'function'
-                return coroutine.wrap(x)
-            elseif type(x) == 'thread'
-                return coroutine.resume, x, nil
-            elseif mt = getmetatable(x)
-                if mt.__pairs
-                    return mt.__pairs(x)
-            return _pairs(x)
         for k,v in pairs(AST) do @environment[k] = v
         @environment.Lua = Lua
         @environment.Nomsu = Nomsu
@@ -400,12 +363,12 @@ class NomsuCompiler
                     error("Circular import, this loops forever: #{concat loop, " -> "}")
 
             insert _running_files, filename
-            if filename\match("%.lua$")
+            if match(filename, "%.lua$")
                 file = assert(FILE_CACHE[filename], "Could not find file: #{filename}")
                 ret = @run_lua(Lua(Source(filename, 1, #file), file))
-            elseif filename\match("%.nom$") or filename\match("^/dev/fd/[012]$")
+            elseif match(filename, "%.nom$") or match(filename, "^/dev/fd/[012]$")
                 if not @skip_precompiled -- Look for precompiled version
-                    lua_filename = filename\gsub("%.nom$", ".lua")
+                    lua_filename = gsub(filename, "%.nom$", ".lua")
                     file = FILE_CACHE[lua_filename]
                     if file
                         ret = @run_lua(Lua(Source(filename, 1, #file), file))
@@ -426,7 +389,7 @@ class NomsuCompiler
     run_lua: (lua)=>
         assert(type(lua) != 'string', "Attempt to run lua string instead of Lua (object)")
         lua_string = tostring(lua)
-        run_lua_fn, err = load(lua_string, nil and tostring(lua.source), "t", @environment)
+        run_lua_fn, err = load(lua_string, tostring(lua.source), "t", @environment)
         if not run_lua_fn
             n = 1
             fn = ->
@@ -526,11 +489,8 @@ class NomsuCompiler
                 make_tree = (t)->
                     unless AST.is_syntax_tree(t)
                         return repr(t)
-                    if t.value
-                        return t.type.."("..repr(tostring t.source)..", "..repr(t.value)..")"
-                    else
-                        bits = [make_tree(bit) for bit in *t]
-                        return t.type.."("..repr(tostring t.source)..", "..table.concat(bits, ", ")..")"
+                    bits = [make_tree(bit) for bit in *t]
+                    return t.type.."("..repr(tostring t.source)..", "..table.concat(bits, ", ")..")"
                 Lua.Value tree.source, make_tree(tree[1])
             
             when "Block"
@@ -555,7 +515,7 @@ class NomsuCompiler
                         string_buffer = ""
                     bit_lua = @tree_to_lua(bit)
                     unless bit_lua.is_value
-                        src = '    '..tostring(@tree_to_nomsu(bit))\gsub('\n','\n    ')
+                        src = '    '..gsub(tostring(@tree_to_nomsu(bit)), '\n','\n    ')
                         line = "#{bit.source.filename}:#{pos_to_line(FILE_CACHE[bit.source.filename], bit.source.start)}"
                         compile_error bit,
                             "Cannot use:\n%s\nas a string interpolation value, since it's not an expression."
@@ -582,8 +542,8 @@ class NomsuCompiler
                             "Cannot use:\n%s\nas a list item, since it's not an expression."
                     lua\append item_lua
                     item_string = tostring(item_lua)
-                    last_line = item_string\match("[^\n]*$")
-                    if item_string\match("\n")
+                    last_line = match(item_string, "[^\n]*$")
+                    if match(item_string, "\n")
                         line_length = #last_line
                     else
                         line_length += #last_line
@@ -605,7 +565,7 @@ class NomsuCompiler
                     lua\append entry_lua
                     entry_lua_str = tostring(entry_lua)
                     -- TODO: maybe make this more accurate? It's only a heuristic, so eh...
-                    last_line = entry_lua_str\match("\n([^\n]*)$")
+                    last_line = match(entry_lua_str, "\n([^\n]*)$")
                     if last_line
                         line_length = #last_line
                     else
@@ -630,10 +590,10 @@ class NomsuCompiler
                 unless value_lua.is_value
                     compile_error tree[2],
                         "Cannot use:\n%s\nas a dict value, since it's not an expression."
-                key_str = tostring(key_lua)\match([=[["']([a-zA-Z_][a-zA-Z0-9_]*)['"]]=])
+                key_str = match(tostring(key_lua), [=[["']([a-zA-Z_][a-zA-Z0-9_]*)['"]]=])
                 return if key_str
                     Lua tree.source, key_str,"=",value_lua
-                elseif tostring(key_lua)\sub(1,1) == "["
+                elseif sub(tostring(key_lua),1,1) == "["
                     -- NOTE: this *must* use a space after the [ to avoid freaking out
                     -- Lua's parser if the inner expression is a long string. Lua
                     -- parses x[[[y]]] as x("[y]"), not as x["y"]
@@ -646,7 +606,7 @@ class NomsuCompiler
                 unless lua.is_value
                     compile_error tree[1],
                         "Cannot index:\n%s\nsince it's not an expression."
-                first_char = tostring(lua)\sub(1,1)
+                first_char = sub(tostring(lua),1,1)
                 if first_char == "{" or first_char == '"' or first_char == "["
                     lua\parenthesize!
 
@@ -657,9 +617,9 @@ class NomsuCompiler
                         compile_error key,
                             "Cannot use:\n%s\nas an index, since it's not an expression."
                     key_lua_str = tostring(key_lua)
-                    if lua_id = key_lua_str\match("^['\"]([a-zA-Z_][a-zA-Z0-9_]*)['\"]$")
+                    if lua_id = match(key_lua_str, "^['\"]([a-zA-Z_][a-zA-Z0-9_]*)['\"]$")
                         lua\append ".#{lua_id}"
-                    elseif key_lua_str\sub(1,1) == '['
+                    elseif sub(key_lua_str,1,1) == '['
                         -- NOTE: this *must* use a space after the [ to avoid freaking out
                         -- Lua's parser if the inner expression is a long string. Lua
                         -- parses x[[[y]]] as x("[y]"), not as x["y"]
@@ -669,10 +629,10 @@ class NomsuCompiler
                 return lua
 
             when "Number"
-                Lua.Value(tree.source, tostring(tree.value))
+                Lua.Value(tree.source, tostring(tree[1]))
 
             when "Var"
-                Lua.Value(tree.source, string.as_lua_id(tree.value))
+                Lua.Value(tree.source, string.as_lua_id(tree[1]))
             
             else
                 error("Unknown type: #{tree.type}")
@@ -713,7 +673,7 @@ class NomsuCompiler
                             if arg_nomsu and #arg_nomsu < MAX_LINE
                                 if bit.type == "Action"
                                     if can_use_colon and i > 1
-                                        nomsu\append next_space\match("[^ ]*"), ": ", arg_nomsu
+                                        nomsu\append match(next_space,"[^ ]*"), ": ", arg_nomsu
                                         next_space = "\n.."
                                         last_colon = i
                                     else
@@ -737,7 +697,7 @@ class NomsuCompiler
                                 nomsu\append next_space, arg_nomsu
                                 next_space = "\n.."
 
-                            if next_space == " " and #(tostring(nomsu)\match("[^\n]*$")) > MAX_LINE
+                            if next_space == " " and #(match(tostring(nomsu),"[^\n]*$")) > MAX_LINE
                                 next_space = "\n.."
                     return nomsu
 
@@ -764,7 +724,7 @@ class NomsuCompiler
                     nomsu\append line
                     if i < #tree
                         nomsu\append "\n"
-                        if tostring(line)\match("\n")
+                        if match(tostring(line), "\n")
                             nomsu\append "\n"
                 return nomsu
 
@@ -774,7 +734,7 @@ class NomsuCompiler
                     for bit in *tree
                         if type(bit) == 'string'
                             -- TODO: unescape better?
-                            nomsu\append (bit\gsub("\\","\\\\")\gsub("\n","\\n"))
+                            nomsu\append (gsub(gsub(bit,"\\","\\\\"),"\n","\\n"))
                         else
                             interp_nomsu = @tree_to_nomsu(bit, true)
                             if interp_nomsu
@@ -791,7 +751,8 @@ class NomsuCompiler
                     nomsu = Nomsu(tree.source, '".."\n    ')
                     for i, bit in ipairs @
                         if type(bit) == 'string'
-                            nomsu\append (bit\gsub("\\","\\\\")\gsub("\n","\n    "))
+                            -- TODO: unescape better?
+                            nomsu\append (gsub(gsub(bit,"\\","\\\\"),"\n","\\n"))
                         else
                             interp_nomsu = @tree_to_nomsu(bit, true)
                             if interp_nomsu
@@ -902,10 +863,10 @@ class NomsuCompiler
                 return nomsu
             
             when "Number"
-                return Nomsu(tree.source, tostring(tree.value))
+                return Nomsu(tree.source, tostring(tree[1]))
 
             when "Var"
-                return Nomsu(tree.source, "%", tree.value)
+                return Nomsu(tree.source, "%", tree[1])
             
             else
                 error("Unknown type: #{tree.type}")
diff --git a/nomsu.peg b/nomsu.peg
index 2de5292..2654f21 100644
--- a/nomsu.peg
+++ b/nomsu.peg
@@ -98,11 +98,11 @@ text_interpolation:
     inline_text_interpolation /
     ("\" indented_expression nodent "..")
 
-number (Number): {| {:value: (("-"? (([0-9]+ "." [0-9]+) / ("." [0-9]+) / ([0-9]+)))-> tonumber) :} |}
+number (Number): {| (("-"? (([0-9]+ "." [0-9]+) / ("." [0-9]+) / ([0-9]+)))-> tonumber) |}
 
 -- Variables can be nameless (i.e. just %) and can't contain operators like apostrophe
 -- which is a hack to allow %'s to parse as "%" and "' s" separately
-variable (Var): "%" {| {:value: (%ident_char+ ((!"'" %operator_char+) / %ident_char+)*)? :} |}
+variable (Var): "%" {| {(%ident_char+ ((!"'" %operator_char+) / %ident_char+)*)?} |}
 
 inline_list (List):
     !('[..]')
diff --git a/nomsu_tree.lua b/nomsu_tree.lua
index 5aeefe8..96e5031 100644
--- a/nomsu_tree.lua
+++ b/nomsu_tree.lua
@@ -12,17 +12,18 @@ AST.is_syntax_tree = function(n)
   return type(n) == 'table' and getmetatable(n) and AST[n.type] == getmetatable(n)
 end
 local Tree
-Tree = function(name, leaf_or_branch, methods)
+Tree = function(name, methods)
   local cls = methods or { }
-  local is_multi = leaf_or_branch == 'branch'
   do
     cls.type = name
+    cls.__class = cls
+    cls.__name = name
     cls.is_instance = function(self, x)
       return getmetatable(x) == self
     end
     cls.__index = cls
     cls.__tostring = function(self)
-      return tostring(self.name) .. "(#{@value and repr(@value) or table.concat([repr(v) for v in *@]), ', '})"
+      return tostring(self.name) .. "(#{table.concat([repr(v) for v in *@]), ', '})"
     end
     cls.map = function(self, fn)
       do
@@ -31,21 +32,26 @@ Tree = function(name, leaf_or_branch, methods)
           return replacement
         end
       end
-      if self.value then
-        return self
-      end
-      local new_vals
-      do
-        local _accum_0 = { }
-        local _len_0 = 1
-        for _index_0 = 1, #self do
-          local v = self[_index_0]
-          _accum_0[_len_0] = v.map and v:map(fn) or v
-          _len_0 = _len_0 + 1
+      local made_changes, new_vals = false, { }
+      for i, v in ipairs(self) do
+        if AST.is_syntax_tree(v) then
+          do
+            local replacement = v:map(fn)
+            if replacement then
+              if replacement ~= v then
+                made_changes = true
+                v = replacement
+              end
+            end
+          end
         end
-        new_vals = _accum_0
+        new_vals[i] = v
       end
-      return getmetatable(self)(self.source, unpack(new_vals))
+      if not (made_changes) then
+        return self
+      end
+      local replacement = getmetatable(self)(self.source, unpack(new_vals))
+      return replacement
     end
   end
   AST[name] = setmetatable(cls, {
@@ -57,18 +63,10 @@ Tree = function(name, leaf_or_branch, methods)
         source = Source:from_string(source)
       end
       assert(Source:is_instance(source))
-      local inst
-      if is_multi then
-        inst = {
-          source = source,
-          ...
-        }
-      else
-        inst = {
-          source = source,
-          value = ...
-        }
-      end
+      local inst = {
+        source = source,
+        ...
+      }
       setmetatable(inst, self)
       if inst.__init then
         inst:__init()
@@ -77,16 +75,16 @@ Tree = function(name, leaf_or_branch, methods)
     end
   })
 end
-Tree("Number", 'leaf')
-Tree("Var", 'leaf')
-Tree("Block", 'branch')
-Tree("EscapedNomsu", 'branch')
-Tree("Text", 'branch')
-Tree("List", 'branch')
-Tree("Dict", 'branch')
-Tree("DictEntry", 'branch')
-Tree("IndexChain", 'branch')
-Tree("Action", 'branch', {
+Tree("Number")
+Tree("Var")
+Tree("Block")
+Tree("EscapedNomsu")
+Tree("Text")
+Tree("List")
+Tree("Dict")
+Tree("DictEntry")
+Tree("IndexChain")
+Tree("Action", {
   __init = function(self)
     local stub_bits
     do
@@ -107,7 +105,7 @@ Tree("Action", 'branch', {
       local _len_0 = 1
       for _index_0 = 1, #self do
         local a = self[_index_0]
-        _accum_0[_len_0] = type(a) == "string" and a or "%" .. tostring(a.value)
+        _accum_0[_len_0] = type(a) == "string" and a or "%" .. tostring(a[1])
         _len_0 = _len_0 + 1
       end
       return _accum_0
diff --git a/nomsu_tree.moon b/nomsu_tree.moon
index fe1c4f4..315571a 100644
--- a/nomsu_tree.moon
+++ b/nomsu_tree.moon
@@ -9,19 +9,28 @@ AST.is_syntax_tree = (n)->
     type(n) == 'table' and getmetatable(n) and AST[n.type] == getmetatable(n)
 
 -- Helper method:
-Tree = (name, leaf_or_branch, methods)->
+Tree = (name, methods)->
     cls = methods or {}
-    is_multi = leaf_or_branch == 'branch'
     with cls
         .type = name
+        .__class = cls
+        .__name = name
         .is_instance = (x)=> getmetatable(x) == @
         .__index = cls
-        .__tostring = => "#{@name}(#{@value and repr(@value) or table.concat([repr(v) for v in *@]), ', '})"
+        .__tostring = => "#{@name}(#{table.concat([repr(v) for v in *@]), ', '})"
         .map = (fn)=>
             if replacement = fn(@) then return replacement
-            if @value then return @
-            new_vals = [v.map and v\map(fn) or v for v in *@]
-            return getmetatable(self)(@source, unpack(new_vals))
+            made_changes, new_vals = false, {}
+            for i,v in ipairs @
+                if AST.is_syntax_tree(v)
+                    if replacement = v\map(fn)
+                        if replacement ~= v
+                            made_changes = true
+                            v = replacement
+                new_vals[i] = v
+            return @ unless made_changes
+            replacement = getmetatable(self)(@source, unpack(new_vals))
+            return replacement
 
     AST[name] = setmetatable cls,
         __tostring: => @name
@@ -29,25 +38,25 @@ Tree = (name, leaf_or_branch, methods)->
             if type(source) == 'string'
                 source = Source\from_string(source)
             assert(Source\is_instance(source))
-            inst = if is_multi then {:source, ...} else {:source, value:...}
+            inst = {:source, ...}
             setmetatable(inst, @)
             if inst.__init then inst\__init!
             return inst
 
-Tree "Number", 'leaf'
-Tree "Var", 'leaf'
-Tree "Block", 'branch'
-Tree "EscapedNomsu", 'branch'
-Tree "Text", 'branch'
-Tree "List", 'branch'
-Tree "Dict", 'branch'
-Tree "DictEntry", 'branch'
-Tree "IndexChain", 'branch'
-Tree "Action", 'branch',
+Tree "Number"
+Tree "Var"
+Tree "Block"
+Tree "EscapedNomsu"
+Tree "Text"
+Tree "List"
+Tree "Dict"
+Tree "DictEntry"
+Tree "IndexChain"
+Tree "Action",
     __init: =>
         stub_bits = [type(a) == 'string' and a or '%' for a in *@]
         @stub = concat stub_bits, " "
     get_spec: =>
-        concat [type(a) == "string" and a or "%#{a.value}" for a in *@], " "
+        concat [type(a) == "string" and a or "%#{a[1]}" for a in *@], " "
 
 return AST
diff --git a/tests/control_flow.nom b/tests/control_flow.nom
index 886b59c..5553811 100644
--- a/tests/control_flow.nom
+++ b/tests/control_flow.nom
@@ -193,14 +193,15 @@ assume
             return %n
     ..= 6
 
-%nums <- []
-for % in
-    values
-        -> 4
-        -> 5
-        -> 6
-..
-    add % to %nums
-
-assume (%nums = [4,5,6]) or barf "Coroutine iteration failed"
+#
+    %nums <- []
+    for % in
+        values
+            -> 4
+            -> 5
+            -> 6
+    ..
+        add % to %nums
+
+    assume (%nums = [4,5,6]) or barf "Coroutine iteration failed"