lua/json/encode/others.lua

   1 --[[
   2         Licensed according to the included 'LICENSE' document
   3         Author: Thomas Harning Jr <harningt@gmail.com>
   4 ]]
   5 local tostring = tostring
   6
   7 local assert = assert
   8 local jsonutil = require("json.util")
   9 local type = type
  10
  11 _ENV = nil
  12
  13 -- Shortcut that works
  14 local encodeBoolean = tostring
  15
  16 local defaultOptions = {
  17         allowUndefined = true,
  18         null = jsonutil.null,
  19         undefined = jsonutil.undefined
  20 }
  21
  22 local modeOptions = {}
  23
  24 modeOptions.strict = {
  25         allowUndefined = false
  26 }
  27
  28 local function mergeOptions(options, mode)
  29         jsonutil.doOptionMerge(options, false, 'others', defaultOptions, mode and modeOptions[mode])
  30 end
  31 local function getEncoder(options)
  32         options = options and jsonutil.merge({}, defaultOptions, options) or defaultOptions
  33         local function encodeOthers(value, state)
  34                 if value == options.null then
  35                         return 'null'
  36                 elseif value == options.undefined then
  37                         assert(options.allowUndefined, "Invalid value: Unsupported 'Undefined' parameter")
  38                         return 'undefined'
  39                 else
  40                         return false
  41                 end
  42         end
  43         local function encodeBoolean(value, state)
  44                 return value and 'true' or 'false'
  45         end
  46         local nullType = type(options.null)
  47         local undefinedType = options.undefined and type(options.undefined)
  48         -- Make sure that all of the types handled here are handled
  49         local ret = {
  50                 boolean = encodeBoolean,
  51                 ['nil'] = function() return 'null' end,
  52                 [nullType] = encodeOthers
  53         }
  54         if undefinedType then
  55                 ret[undefinedType] = encodeOthers
  56         end
  57         return ret
  58 end
  59
  60 local others = {
  61         encodeBoolean = encodeBoolean,
  62         mergeOptions = mergeOptions,
  63         getEncoder = getEncoder
  64 }
  65
  66 return others