arbitrary type support (e.g., LuaJIT's cdata)

inspect.lua

@@ -5,6 +5,17 @@
 -- inspired by http://lua-users.org/wiki/TableSerialization
 -----------------------------------------------------------------------------------------------------------------------
 
+local type = type
+local ipairs, pairs = ipairs, pairs
+local string = string
+local table = table
+local tostring = tostring
+local rawget = rawget
+local pcall = pcall
+local getmetatable, setmetatable = getmetatable, setmetatable
+local rawget, rawset = rawget, rawset
+local math = math
+
 local inspect ={}
 inspect.__VERSION = '1.2.0'
 
@@ -41,10 +52,15 @@ local function isDictionaryKey(k, length)
   return not isArrayKey(k, length)
 end
 
-local sortOrdersByType = {
+local sortOrdersByType = setmetatable({
   ['number']   = 1, ['boolean']  = 2, ['string'] = 3, ['table'] = 4,
   ['function'] = 5, ['userdata'] = 6, ['thread'] = 7
-}
+},
+{ __index = function (t, k)
+  if not rawget(t, k) then
+    return math.huge
+  end
+end })
 
 local function sortKeys(a, b)
   local ta, tb = type(a), type(b)
@@ -73,6 +89,26 @@ local function getToStringResultSafely(t, mt)
   return string
 end
 
+local inspectorMaxIdsMetaTable = {
+  __index = function (t, k)
+    if not rawget(t, k) then
+      rawset(t, k, 0)
+    end
+    return 0
+  end
+}
+
+local inspectorIdsMetaTable = {
+  __index = function (t, k)
+    local v = rawget(t, k)
+    if not v then
+      rawset(t, k, setmetatable({}, {__mode = "kv"}))
+      v = rawget(t, k)
+    end
+    return v
+  end
+}
+
 local Inspector = {}
 
 function Inspector:new(t, depth)
@@ -80,18 +116,8 @@ function Inspector:new(t, depth)
     buffer = {},
     depth = depth,
     level = 0,
-    maxIds = {
+    maxIds = setmetatable({}, inspectorMaxIdsMetaTable),
-      ['function'] = 0,
+    ids = setmetatable({}, inspectorIdsMetaTable),
-      ['userdata'] = 0,
-      ['thread']   = 0,
-      ['table']    = 0
-    },
-    ids = {
-      ['function'] = setmetatable({}, {__mode = "kv"}),
-      ['userdata'] = setmetatable({}, {__mode = "kv"}),
-      ['thread']   = setmetatable({}, {__mode = "kv"}),
-      ['table']    = setmetatable({}, {__mode = "kv"})
-    },
     tableAppearances = setmetatable({}, {__mode = "k"})
   }