Merge 0e6634a54e into dbf4b2dd2e

json.lua

@@ -22,7 +22,10 @@
 -- SOFTWARE.
 --
 
-local json = { _version = "0.1.2" }
+local json = { 
+	_version = "0.1.2" ,
+	SPARSELIMIT = 100,			-- To set the limit on how long sparse arrays can be
+}
 
 -------------------------------------------------------------------------------
 -- Encode
@@ -64,32 +67,39 @@ local function encode_table(val, stack)
 	if stack[val] then error("circular reference") end
 
 	stack[val] = true
+	-- Check whether to treat as a array or object
+	local array = true
+	local length = 0
+	local nLen = 0
+	local count = 0
+	for k,v in pairs(val) do
+		if (type(k) ~= "number" or k<=0 or k%1 ~= 0) and not (k == "n" and type(v) == "number") then
+			array = nil
+			break	-- Treat as object
+		else
+			if k > length then 
+				length = k
+			end
+			if k == "n" and type(v) == "number" then
+				nLen = v
+			end
+			count = count + 1
+		end
+	end
 
-  if rawget(val, 1) ~= nil or next(val) == nil then
+	if nLen > length then
-    -- Treat as array -- check keys are valid and it is not sparse
+		length = nLen
-    local n = 0
-    for k in pairs(val) do
-      if type(k) ~= "number" then
-        error("invalid table: mixed or invalid key types")
-      end
-      n = n + 1
-    end
-    if n ~= #val then
-      error("invalid table: sparse array")
 	end
+	if array and not (length > SPARSELIMIT and count ~= length) then	-- Check Array detected but sparse > 100 length then treat as object
 		-- Encode
-    for i, v in ipairs(val) do
+		for i=1,length do
-      table.insert(res, encode(v, stack))
+			table.insert(res, encode(val[i], stack))
 		end
 		stack[val] = nil
 		return "[" .. table.concat(res, ",") .. "]"
-
 	else
 		-- Treat as an object
 		for k, v in pairs(val) do
-      if type(k) ~= "string" then
-        error("invalid table: mixed or invalid key types")
-      end
 			table.insert(res, encode(k, stack) .. ":" .. encode(v, stack))
 		end
 		stack[val] = nil
@@ -108,7 +118,7 @@ local function encode_number(val)
 	if val ~= val or val <= -math.huge or val >= math.huge then
 		error("unexpected number value '" .. tostring(val) .. "'")
 	end
-  return string.format("%.14g", val)
+	return string.format("%.14g",val)
 end