diff --git a/builtin_metatables.lua b/builtin_metatables.lua
index e579e6c..f659ad3 100644
--- a/builtin_metatables.lua
+++ b/builtin_metatables.lua
@@ -1,6 +1,9 @@
 require("text")
 local number_mt = {
   __type = "a Number",
+  __len = function(self)
+    return self
+  end,
   as_lua = tostring,
   as_nomsu = tostring,
   as_text = tostring,
@@ -23,12 +26,24 @@ number_mt.__index = number_mt
 debug.setmetatable(0, number_mt)
 local bool_mt = {
   __type = "a Boolean",
+  __len = function(self)
+    return self and 1 or 0
+  end,
   as_lua = tostring,
   as_nomsu = function(self)
     return self and "yes" or "no"
   end,
   as_text = function(self)
     return self and "yes" or "no"
+  end,
+  _and = function(self, cond)
+    return self and cond
+  end,
+  _or = function(self, cond)
+    return self or cond
+  end,
+  xor = function(self, cond)
+    return self == (not cond)
   end
 }
 bool_mt.__index = bool_mt
@@ -37,6 +52,126 @@ local fn_mt = {
   __type = "an Action",
   as_text = function(self)
     return (tostring(self):gsub("function", "Action"))
+  end,
+  __add = function(self, other)
+    if type(self) == 'function' and type(other) == 'function' then
+      return function(...)
+        return (self(...) + other(...))
+      end
+    elseif type(self) == 'function' then
+      return function(...)
+        return (self(...) + other)
+      end
+    else
+      return function(...)
+        return (self + other(...))
+      end
+    end
+  end,
+  __sub = function(self, other)
+    if type(self) == 'function' and type(other) == 'function' then
+      return function(...)
+        return (self(...) - other(...))
+      end
+    elseif type(self) == 'function' then
+      return function(...)
+        return (self(...) - other)
+      end
+    else
+      return function(...)
+        return (self - other(...))
+      end
+    end
+  end,
+  __mul = function(self, other)
+    if type(self) == 'function' and type(other) == 'function' then
+      return function(...)
+        return (self(...) * other(...))
+      end
+    elseif type(self) == 'function' then
+      return function(...)
+        return (self(...) * other)
+      end
+    else
+      return function(...)
+        return (self * other(...))
+      end
+    end
+  end,
+  __div = function(self, other)
+    if type(self) == 'function' and type(other) == 'function' then
+      return function(...)
+        return (self(...)(other(...)))
+      end
+    elseif type(self) == 'function' then
+      return function(...)
+        return (self(...)(other))
+      end
+    else
+      return function(...)
+        return (self(other(...)))
+      end
+    end
+  end,
+  __mod = function(self, other)
+    if type(self) == 'function' and type(other) == 'function' then
+      return function(...)
+        return (self(...) % other(...))
+      end
+    elseif type(self) == 'function' then
+      return function(...)
+        return (self(...) % other)
+      end
+    else
+      return function(...)
+        return (self % other(...))
+      end
+    end
+  end,
+  __band = function(self, other)
+    if type(self) == 'function' and type(other) == 'function' then
+      return function(...)
+        return (self(...) and other(...))
+      end
+    elseif type(self) == 'function' then
+      return function(...)
+        return (self(...) and other)
+      end
+    else
+      return function(...)
+        return (self and other(...))
+      end
+    end
+  end,
+  __bor = function(self, other)
+    if type(self) == 'function' and type(other) == 'function' then
+      return function(...)
+        return (self(...) or other(...))
+      end
+    elseif type(self) == 'function' then
+      return function(...)
+        return (self(...) or other)
+      end
+    else
+      return function(...)
+        return (self or other(...))
+      end
+    end
+  end,
+  __bxor = function(self, other)
+    if type(self) == 'function' and type(other) == 'function' then
+      return function(...)
+        return (self(...) ~= other(...))
+      end
+    elseif type(self) == 'function' then
+      return function(...)
+        return (self(...) ~= other)
+      end
+    else
+      return function(...)
+        return (self ~= other(...))
+      end
+    end
   end
 }
 fn_mt.__index = fn_mt
diff --git a/builtin_metatables.moon b/builtin_metatables.moon
index eb7e27e..ac8beff 100644
--- a/builtin_metatables.moon
+++ b/builtin_metatables.moon
@@ -3,6 +3,7 @@ require "text"
 
 number_mt =
     __type: "a Number"
+    __len: => @
     as_lua: tostring
     as_nomsu: tostring
     as_text: tostring
@@ -17,15 +18,59 @@ debug.setmetatable 0, number_mt
 
 bool_mt =
     __type: "a Boolean"
+    __len: => @ and 1 or 0
     as_lua: tostring
     as_nomsu: => @ and "yes" or "no"
     as_text: => @ and "yes" or "no"
+    _and: (cond)=> @ and cond
+    _or: (cond)=> @ or cond
+    xor: (cond)=> @ == (not cond)
 bool_mt.__index = bool_mt
 debug.setmetatable true, bool_mt
 
 fn_mt =
     __type: "an Action"
     as_text: => (tostring(@)\gsub("function", "Action"))
+    __add: (other)=>
+        if type(@) == 'function' and type(other) == 'function'
+            (...)-> (@(...) + other(...))
+        elseif type(@) == 'function' then (...)-> (@(...) + other)
+        else (...)-> (@ + other(...))
+    __sub: (other)=>
+        if type(@) == 'function' and type(other) == 'function'
+            (...)-> (@(...) - other(...))
+        elseif type(@) == 'function' then (...)-> (@(...) - other)
+        else (...)-> (@ - other(...))
+    __mul: (other)=>
+        if type(@) == 'function' and type(other) == 'function'
+            (...)-> (@(...) * other(...))
+        elseif type(@) == 'function' then (...)-> (@(...) * other)
+        else (...)-> (@ * other(...))
+    __div: (other)=>
+        if type(@) == 'function' and type(other) == 'function'
+            (...)-> (@(...)  other(...))
+        elseif type(@) == 'function' then (...)-> (@(...)  other)
+        else (...)-> (@  other(...))
+    __mod: (other)=>
+        if type(@) == 'function' and type(other) == 'function'
+            (...)-> (@(...) % other(...))
+        elseif type(@) == 'function' then (...)-> (@(...) % other)
+        else (...)-> (@ % other(...))
+    __band: (other)=>
+        if type(@) == 'function' and type(other) == 'function'
+            (...)-> (@(...) and other(...))
+        elseif type(@) == 'function' then (...)-> (@(...) and other)
+        else (...)-> (@ and other(...))
+    __bor: (other)=>
+        if type(@) == 'function' and type(other) == 'function'
+            (...)-> (@(...) or other(...))
+        elseif type(@) == 'function' then (...)-> (@(...) or other)
+        else (...)-> (@ or other(...))
+    __bxor: (other)=>
+        if type(@) == 'function' and type(other) == 'function'
+            (...)-> (@(...) != other(...))
+        elseif type(@) == 'function' then (...)-> (@(...) != other)
+        else (...)-> (@ != other(...))
 fn_mt.__index = fn_mt
 debug.setmetatable (->), fn_mt