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@@ -0,0 +1,714 @@
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+-- Module options:
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+local always_try_using_lpeg = true
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+local register_global_module_table = false
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+local global_module_name = 'json'
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+
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+--[==[
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+
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+David Kolf's JSON module for Lua 5.1/5.2
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+
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+Version 2.5
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+
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+
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+For the documentation see the corresponding readme.txt or visit
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+<http://dkolf.de/src/dkjson-lua.fsl/>.
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+
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+You can contact the author by sending an e-mail to 'david' at the
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+domain 'dkolf.de'.
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+
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+
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+Copyright (C) 2010-2013 David Heiko Kolf
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+
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+Permission is hereby granted, free of charge, to any person obtaining
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+a copy of this software and associated documentation files (the
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+"Software"), to deal in the Software without restriction, including
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+without limitation the rights to use, copy, modify, merge, publish,
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+distribute, sublicense, and/or sell copies of the Software, and to
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+permit persons to whom the Software is furnished to do so, subject to
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+the following conditions:
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+
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+The above copyright notice and this permission notice shall be
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+included in all copies or substantial portions of the Software.
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+
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+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
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+BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
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+ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
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+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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+SOFTWARE.
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+
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+--]==]
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+
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+-- global dependencies:
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+local pairs, type, tostring, tonumber, getmetatable, setmetatable, rawset =
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+ pairs, type, tostring, tonumber, getmetatable, setmetatable, rawset
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+local error, require, pcall, select = error, require, pcall, select
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+local floor, huge = math.floor, math.huge
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+local strrep, gsub, strsub, strbyte, strchar, strfind, strlen, strformat =
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+ string.rep, string.gsub, string.sub, string.byte, string.char,
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+ string.find, string.len, string.format
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+local strmatch = string.match
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+local concat = table.concat
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+
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+local json = { version = "dkjson 2.5" }
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+
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+if register_global_module_table then
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+ _G[global_module_name] = json
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+end
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+
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+local _ENV = nil -- blocking globals in Lua 5.2
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+
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+pcall (function()
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+ -- Enable access to blocked metatables.
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+ -- Don't worry, this module doesn't change anything in them.
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+ local debmeta = require "debug".getmetatable
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+ if debmeta then getmetatable = debmeta end
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+end)
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+
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+json.null = setmetatable ({}, {
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+ __tojson = function () return "null" end
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+})
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+
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+local function isarray (tbl)
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+ local max, n, arraylen = 0, 0, 0
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+ for k,v in pairs (tbl) do
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+ if k == 'n' and type(v) == 'number' then
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+ arraylen = v
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+ if v > max then
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+ max = v
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+ end
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+ else
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+ if type(k) ~= 'number' or k < 1 or floor(k) ~= k then
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+ return false
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+ end
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+ if k > max then
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+ max = k
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+ end
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+ n = n + 1
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+ end
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+ end
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+ if max > 10 and max > arraylen and max > n * 2 then
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+ return false -- don't create an array with too many holes
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+ end
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+ return true, max
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+end
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+
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+local escapecodes = {
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+ ["\""] = "\\\"", ["\\"] = "\\\\", ["\b"] = "\\b", ["\f"] = "\\f",
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+ ["\n"] = "\\n", ["\r"] = "\\r", ["\t"] = "\\t"
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+}
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+
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+local function escapeutf8 (uchar)
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+ local value = escapecodes[uchar]
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+ if value then
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+ return value
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+ end
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+ local a, b, c, d = strbyte (uchar, 1, 4)
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+ a, b, c, d = a or 0, b or 0, c or 0, d or 0
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+ if a <= 0x7f then
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+ value = a
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+ elseif 0xc0 <= a and a <= 0xdf and b >= 0x80 then
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+ value = (a - 0xc0) * 0x40 + b - 0x80
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+ elseif 0xe0 <= a and a <= 0xef and b >= 0x80 and c >= 0x80 then
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+ value = ((a - 0xe0) * 0x40 + b - 0x80) * 0x40 + c - 0x80
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+ elseif 0xf0 <= a and a <= 0xf7 and b >= 0x80 and c >= 0x80 and d >= 0x80 then
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+ value = (((a - 0xf0) * 0x40 + b - 0x80) * 0x40 + c - 0x80) * 0x40 + d - 0x80
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+ else
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+ return ""
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+ end
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+ if value <= 0xffff then
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+ return strformat ("\\u%.4x", value)
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+ elseif value <= 0x10ffff then
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+ -- encode as UTF-16 surrogate pair
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+ value = value - 0x10000
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+ local highsur, lowsur = 0xD800 + floor (value/0x400), 0xDC00 + (value % 0x400)
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+ return strformat ("\\u%.4x\\u%.4x", highsur, lowsur)
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+ else
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+ return ""
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+ end
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+end
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+
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+local function fsub (str, pattern, repl)
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+ -- gsub always builds a new string in a buffer, even when no match
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+ -- exists. First using find should be more efficient when most strings
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+ -- don't contain the pattern.
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+ if strfind (str, pattern) then
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+ return gsub (str, pattern, repl)
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+ else
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+ return str
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+ end
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+end
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+
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+local function quotestring (value)
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+ -- based on the regexp "escapable" in https://github.com/douglascrockford/JSON-js
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+ value = fsub (value, "[%z\1-\31\"\\\127]", escapeutf8)
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+ if strfind (value, "[\194\216\220\225\226\239]") then
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+ value = fsub (value, "\194[\128-\159\173]", escapeutf8)
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+ value = fsub (value, "\216[\128-\132]", escapeutf8)
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+ value = fsub (value, "\220\143", escapeutf8)
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+ value = fsub (value, "\225\158[\180\181]", escapeutf8)
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+ value = fsub (value, "\226\128[\140-\143\168-\175]", escapeutf8)
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+ value = fsub (value, "\226\129[\160-\175]", escapeutf8)
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+ value = fsub (value, "\239\187\191", escapeutf8)
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+ value = fsub (value, "\239\191[\176-\191]", escapeutf8)
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+ end
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+ return "\"" .. value .. "\""
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+end
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+json.quotestring = quotestring
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+
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+local function replace(str, o, n)
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+ local i, j = strfind (str, o, 1, true)
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+ if i then
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+ return strsub(str, 1, i-1) .. n .. strsub(str, j+1, -1)
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+ else
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+ return str
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+ end
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+end
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+
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+-- locale independent num2str and str2num functions
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+local decpoint, numfilter
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+
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+local function updatedecpoint ()
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+ decpoint = strmatch(tostring(0.5), "([^05+])")
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+ -- build a filter that can be used to remove group separators
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+ numfilter = "[^0-9%-%+eE" .. gsub(decpoint, "[%^%$%(%)%%%.%[%]%*%+%-%?]", "%%%0") .. "]+"
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+end
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+
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+updatedecpoint()
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+
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+local function num2str (num)
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+ return replace(fsub(tostring(num), numfilter, ""), decpoint, ".")
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+end
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+
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+local function str2num (str)
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+ local num = tonumber(replace(str, ".", decpoint))
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+ if not num then
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+ updatedecpoint()
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+ num = tonumber(replace(str, ".", decpoint))
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+ end
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+ return num
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+end
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+
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+local function addnewline2 (level, buffer, buflen)
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+ buffer[buflen+1] = "\n"
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+ buffer[buflen+2] = strrep (" ", level)
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+ buflen = buflen + 2
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+ return buflen
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+end
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+
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+function json.addnewline (state)
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+ if state.indent then
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+ state.bufferlen = addnewline2 (state.level or 0,
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+ state.buffer, state.bufferlen or #(state.buffer))
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+ end
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+end
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+
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+local encode2 -- forward declaration
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+
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+local function addpair (key, value, prev, indent, level, buffer, buflen, tables, globalorder, state)
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+ local kt = type (key)
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+ if kt ~= 'string' and kt ~= 'number' then
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+ return nil, "type '" .. kt .. "' is not supported as a key by JSON."
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+ end
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+ if prev then
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+ buflen = buflen + 1
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+ buffer[buflen] = ","
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+ end
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+ if indent then
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+ buflen = addnewline2 (level, buffer, buflen)
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+ end
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+ buffer[buflen+1] = quotestring (key)
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+ buffer[buflen+2] = ":"
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+ return encode2 (value, indent, level, buffer, buflen + 2, tables, globalorder, state)
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+end
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+
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+local function appendcustom(res, buffer, state)
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+ local buflen = state.bufferlen
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+ if type (res) == 'string' then
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+ buflen = buflen + 1
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+ buffer[buflen] = res
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+ end
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+ return buflen
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+end
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+
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+local function exception(reason, value, state, buffer, buflen, defaultmessage)
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+ defaultmessage = defaultmessage or reason
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+ local handler = state.exception
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+ if not handler then
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+ return nil, defaultmessage
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+ else
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+ state.bufferlen = buflen
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+ local ret, msg = handler (reason, value, state, defaultmessage)
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+ if not ret then return nil, msg or defaultmessage end
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+ return appendcustom(ret, buffer, state)
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+ end
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+end
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+
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+function json.encodeexception(reason, value, state, defaultmessage)
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+ return quotestring("<" .. defaultmessage .. ">")
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+end
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+
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+encode2 = function (value, indent, level, buffer, buflen, tables, globalorder, state)
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+ local valtype = type (value)
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+ local valmeta = getmetatable (value)
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+ valmeta = type (valmeta) == 'table' and valmeta -- only tables
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+ local valtojson = valmeta and valmeta.__tojson
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+ if valtojson then
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+ if tables[value] then
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+ return exception('reference cycle', value, state, buffer, buflen)
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+ end
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+ tables[value] = true
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+ state.bufferlen = buflen
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+ local ret, msg = valtojson (value, state)
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+ if not ret then return exception('custom encoder failed', value, state, buffer, buflen, msg) end
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+ tables[value] = nil
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+ buflen = appendcustom(ret, buffer, state)
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+ elseif value == nil then
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+ buflen = buflen + 1
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+ buffer[buflen] = "null"
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+ elseif valtype == 'number' then
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+ local s
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+ if value ~= value or value >= huge or -value >= huge then
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+ -- This is the behaviour of the original JSON implementation.
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+ s = "null"
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+ else
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+ s = num2str (value)
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+ end
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+ buflen = buflen + 1
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+ buffer[buflen] = s
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+ elseif valtype == 'boolean' then
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+ buflen = buflen + 1
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+ buffer[buflen] = value and "true" or "false"
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+ elseif valtype == 'string' then
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+ buflen = buflen + 1
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+ buffer[buflen] = quotestring (value)
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+ elseif valtype == 'table' then
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+ if tables[value] then
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+ return exception('reference cycle', value, state, buffer, buflen)
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+ end
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+ tables[value] = true
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+ level = level + 1
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+ local isa, n = isarray (value)
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+ if n == 0 and valmeta and valmeta.__jsontype == 'object' then
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+ isa = false
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+ end
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+ local msg
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+ if isa then -- JSON array
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+ buflen = buflen + 1
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+ buffer[buflen] = "["
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+ for i = 1, n do
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+ buflen, msg = encode2 (value[i], indent, level, buffer, buflen, tables, globalorder, state)
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+ if not buflen then return nil, msg end
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+ if i < n then
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+ buflen = buflen + 1
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+ buffer[buflen] = ","
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+ end
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+ end
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+ buflen = buflen + 1
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+ buffer[buflen] = "]"
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+ else -- JSON object
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+ local prev = false
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+ buflen = buflen + 1
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+ buffer[buflen] = "{"
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+ local order = valmeta and valmeta.__jsonorder or globalorder
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+ if order then
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+ local used = {}
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+ n = #order
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+ for i = 1, n do
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+ local k = order[i]
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+ local v = value[k]
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+ if v then
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+ used[k] = true
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+ buflen, msg = addpair (k, v, prev, indent, level, buffer, buflen, tables, globalorder, state)
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+ prev = true -- add a seperator before the next element
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+ end
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+ end
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+ for k,v in pairs (value) do
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+ if not used[k] then
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+ buflen, msg = addpair (k, v, prev, indent, level, buffer, buflen, tables, globalorder, state)
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+ if not buflen then return nil, msg end
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+ prev = true -- add a seperator before the next element
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+ end
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+ end
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+ else -- unordered
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+ for k,v in pairs (value) do
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+ buflen, msg = addpair (k, v, prev, indent, level, buffer, buflen, tables, globalorder, state)
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+ if not buflen then return nil, msg end
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+ prev = true -- add a seperator before the next element
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+ end
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+ end
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+ if indent then
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+ buflen = addnewline2 (level - 1, buffer, buflen)
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+ end
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+ buflen = buflen + 1
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+ buffer[buflen] = "}"
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+ end
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+ tables[value] = nil
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+ else
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+ return exception ('unsupported type', value, state, buffer, buflen,
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+ "type '" .. valtype .. "' is not supported by JSON.")
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+ end
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+ return buflen
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+end
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+
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+function json.encode (value, state)
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+ state = state or {}
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+ local oldbuffer = state.buffer
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+ local buffer = oldbuffer or {}
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+ state.buffer = buffer
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+ updatedecpoint()
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+ local ret, msg = encode2 (value, state.indent, state.level or 0,
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+ buffer, state.bufferlen or 0, state.tables or {}, state.keyorder, state)
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+ if not ret then
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+ error (msg, 2)
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+ elseif oldbuffer == buffer then
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+ state.bufferlen = ret
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+ return true
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+ else
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+ state.bufferlen = nil
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+ state.buffer = nil
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+ return concat (buffer)
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+ end
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+end
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+
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+local function loc (str, where)
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+ local line, pos, linepos = 1, 1, 0
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+ while true do
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+ pos = strfind (str, "\n", pos, true)
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+ if pos and pos < where then
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+ line = line + 1
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+ linepos = pos
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+ pos = pos + 1
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+ else
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+ break
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+ end
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+ end
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+ return "line " .. line .. ", column " .. (where - linepos)
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+end
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+
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+local function unterminated (str, what, where)
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+ return nil, strlen (str) + 1, "unterminated " .. what .. " at " .. loc (str, where)
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+end
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+
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+local function scanwhite (str, pos)
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+ while true do
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+ pos = strfind (str, "%S", pos)
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+ if not pos then return nil end
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+ local sub2 = strsub (str, pos, pos + 1)
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|
|
+ if sub2 == "\239\187" and strsub (str, pos + 2, pos + 2) == "\191" then
|
|
|
+ -- UTF-8 Byte Order Mark
|
|
|
+ pos = pos + 3
|
|
|
+ elseif sub2 == "//" then
|
|
|
+ pos = strfind (str, "[\n\r]", pos + 2)
|
|
|
+ if not pos then return nil end
|
|
|
+ elseif sub2 == "/*" then
|
|
|
+ pos = strfind (str, "*/", pos + 2)
|
|
|
+ if not pos then return nil end
|
|
|
+ pos = pos + 2
|
|
|
+ else
|
|
|
+ return pos
|
|
|
+ end
|
|
|
+ end
|
|
|
+end
|
|
|
+
|
|
|
+local escapechars = {
|
|
|
+ ["\""] = "\"", ["\\"] = "\\", ["/"] = "/", ["b"] = "\b", ["f"] = "\f",
|
|
|
+ ["n"] = "\n", ["r"] = "\r", ["t"] = "\t"
|
|
|
+}
|
|
|
+
|
|
|
+local function unichar (value)
|
|
|
+ if value < 0 then
|
|
|
+ return nil
|
|
|
+ elseif value <= 0x007f then
|
|
|
+ return strchar (value)
|
|
|
+ elseif value <= 0x07ff then
|
|
|
+ return strchar (0xc0 + floor(value/0x40),
|
|
|
+ 0x80 + (floor(value) % 0x40))
|
|
|
+ elseif value <= 0xffff then
|
|
|
+ return strchar (0xe0 + floor(value/0x1000),
|
|
|
+ 0x80 + (floor(value/0x40) % 0x40),
|
|
|
+ 0x80 + (floor(value) % 0x40))
|
|
|
+ elseif value <= 0x10ffff then
|
|
|
+ return strchar (0xf0 + floor(value/0x40000),
|
|
|
+ 0x80 + (floor(value/0x1000) % 0x40),
|
|
|
+ 0x80 + (floor(value/0x40) % 0x40),
|
|
|
+ 0x80 + (floor(value) % 0x40))
|
|
|
+ else
|
|
|
+ return nil
|
|
|
+ end
|
|
|
+end
|
|
|
+
|
|
|
+local function scanstring (str, pos)
|
|
|
+ local lastpos = pos + 1
|
|
|
+ local buffer, n = {}, 0
|
|
|
+ while true do
|
|
|
+ local nextpos = strfind (str, "[\"\\]", lastpos)
|
|
|
+ if not nextpos then
|
|
|
+ return unterminated (str, "string", pos)
|
|
|
+ end
|
|
|
+ if nextpos > lastpos then
|
|
|
+ n = n + 1
|
|
|
+ buffer[n] = strsub (str, lastpos, nextpos - 1)
|
|
|
+ end
|
|
|
+ if strsub (str, nextpos, nextpos) == "\"" then
|
|
|
+ lastpos = nextpos + 1
|
|
|
+ break
|
|
|
+ else
|
|
|
+ local escchar = strsub (str, nextpos + 1, nextpos + 1)
|
|
|
+ local value
|
|
|
+ if escchar == "u" then
|
|
|
+ value = tonumber (strsub (str, nextpos + 2, nextpos + 5), 16)
|
|
|
+ if value then
|
|
|
+ local value2
|
|
|
+ if 0xD800 <= value and value <= 0xDBff then
|
|
|
+ -- we have the high surrogate of UTF-16. Check if there is a
|
|
|
+ -- low surrogate escaped nearby to combine them.
|
|
|
+ if strsub (str, nextpos + 6, nextpos + 7) == "\\u" then
|
|
|
+ value2 = tonumber (strsub (str, nextpos + 8, nextpos + 11), 16)
|
|
|
+ if value2 and 0xDC00 <= value2 and value2 <= 0xDFFF then
|
|
|
+ value = (value - 0xD800) * 0x400 + (value2 - 0xDC00) + 0x10000
|
|
|
+ else
|
|
|
+ value2 = nil -- in case it was out of range for a low surrogate
|
|
|
+ end
|
|
|
+ end
|
|
|
+ end
|
|
|
+ value = value and unichar (value)
|
|
|
+ if value then
|
|
|
+ if value2 then
|
|
|
+ lastpos = nextpos + 12
|
|
|
+ else
|
|
|
+ lastpos = nextpos + 6
|
|
|
+ end
|
|
|
+ end
|
|
|
+ end
|
|
|
+ end
|
|
|
+ if not value then
|
|
|
+ value = escapechars[escchar] or escchar
|
|
|
+ lastpos = nextpos + 2
|
|
|
+ end
|
|
|
+ n = n + 1
|
|
|
+ buffer[n] = value
|
|
|
+ end
|
|
|
+ end
|
|
|
+ if n == 1 then
|
|
|
+ return buffer[1], lastpos
|
|
|
+ elseif n > 1 then
|
|
|
+ return concat (buffer), lastpos
|
|
|
+ else
|
|
|
+ return "", lastpos
|
|
|
+ end
|
|
|
+end
|
|
|
+
|
|
|
+local scanvalue -- forward declaration
|
|
|
+
|
|
|
+local function scantable (what, closechar, str, startpos, nullval, objectmeta, arraymeta)
|
|
|
+ local len = strlen (str)
|
|
|
+ local tbl, n = {}, 0
|
|
|
+ local pos = startpos + 1
|
|
|
+ if what == 'object' then
|
|
|
+ setmetatable (tbl, objectmeta)
|
|
|
+ else
|
|
|
+ setmetatable (tbl, arraymeta)
|
|
|
+ end
|
|
|
+ while true do
|
|
|
+ pos = scanwhite (str, pos)
|
|
|
+ if not pos then return unterminated (str, what, startpos) end
|
|
|
+ local char = strsub (str, pos, pos)
|
|
|
+ if char == closechar then
|
|
|
+ return tbl, pos + 1
|
|
|
+ end
|
|
|
+ local val1, err
|
|
|
+ val1, pos, err = scanvalue (str, pos, nullval, objectmeta, arraymeta)
|
|
|
+ if err then return nil, pos, err end
|
|
|
+ pos = scanwhite (str, pos)
|
|
|
+ if not pos then return unterminated (str, what, startpos) end
|
|
|
+ char = strsub (str, pos, pos)
|
|
|
+ if char == ":" then
|
|
|
+ if val1 == nil then
|
|
|
+ return nil, pos, "cannot use nil as table index (at " .. loc (str, pos) .. ")"
|
|
|
+ end
|
|
|
+ pos = scanwhite (str, pos + 1)
|
|
|
+ if not pos then return unterminated (str, what, startpos) end
|
|
|
+ local val2
|
|
|
+ val2, pos, err = scanvalue (str, pos, nullval, objectmeta, arraymeta)
|
|
|
+ if err then return nil, pos, err end
|
|
|
+ tbl[val1] = val2
|
|
|
+ pos = scanwhite (str, pos)
|
|
|
+ if not pos then return unterminated (str, what, startpos) end
|
|
|
+ char = strsub (str, pos, pos)
|
|
|
+ else
|
|
|
+ n = n + 1
|
|
|
+ tbl[n] = val1
|
|
|
+ end
|
|
|
+ if char == "," then
|
|
|
+ pos = pos + 1
|
|
|
+ end
|
|
|
+ end
|
|
|
+end
|
|
|
+
|
|
|
+scanvalue = function (str, pos, nullval, objectmeta, arraymeta)
|
|
|
+ pos = pos or 1
|
|
|
+ pos = scanwhite (str, pos)
|
|
|
+ if not pos then
|
|
|
+ return nil, strlen (str) + 1, "no valid JSON value (reached the end)"
|
|
|
+ end
|
|
|
+ local char = strsub (str, pos, pos)
|
|
|
+ if char == "{" then
|
|
|
+ return scantable ('object', "}", str, pos, nullval, objectmeta, arraymeta)
|
|
|
+ elseif char == "[" then
|
|
|
+ return scantable ('array', "]", str, pos, nullval, objectmeta, arraymeta)
|
|
|
+ elseif char == "\"" then
|
|
|
+ return scanstring (str, pos)
|
|
|
+ else
|
|
|
+ local pstart, pend = strfind (str, "^%-?[%d%.]+[eE]?[%+%-]?%d*", pos)
|
|
|
+ if pstart then
|
|
|
+ local number = str2num (strsub (str, pstart, pend))
|
|
|
+ if number then
|
|
|
+ return number, pend + 1
|
|
|
+ end
|
|
|
+ end
|
|
|
+ pstart, pend = strfind (str, "^%a%w*", pos)
|
|
|
+ if pstart then
|
|
|
+ local name = strsub (str, pstart, pend)
|
|
|
+ if name == "true" then
|
|
|
+ return true, pend + 1
|
|
|
+ elseif name == "false" then
|
|
|
+ return false, pend + 1
|
|
|
+ elseif name == "null" then
|
|
|
+ return nullval, pend + 1
|
|
|
+ end
|
|
|
+ end
|
|
|
+ return nil, pos, "no valid JSON value at " .. loc (str, pos)
|
|
|
+ end
|
|
|
+end
|
|
|
+
|
|
|
+local function optionalmetatables(...)
|
|
|
+ if select("#", ...) > 0 then
|
|
|
+ return ...
|
|
|
+ else
|
|
|
+ return {__jsontype = 'object'}, {__jsontype = 'array'}
|
|
|
+ end
|
|
|
+end
|
|
|
+
|
|
|
+function json.decode (str, pos, nullval, ...)
|
|
|
+ local objectmeta, arraymeta = optionalmetatables(...)
|
|
|
+ return scanvalue (str, pos, nullval, objectmeta, arraymeta)
|
|
|
+end
|
|
|
+
|
|
|
+function json.use_lpeg ()
|
|
|
+ local g = require ("lpeg")
|
|
|
+
|
|
|
+ if g.version() == "0.11" then
|
|
|
+ error "due to a bug in LPeg 0.11, it cannot be used for JSON matching"
|
|
|
+ end
|
|
|
+
|
|
|
+ local pegmatch = g.match
|
|
|
+ local P, S, R = g.P, g.S, g.R
|
|
|
+
|
|
|
+ local function ErrorCall (str, pos, msg, state)
|
|
|
+ if not state.msg then
|
|
|
+ state.msg = msg .. " at " .. loc (str, pos)
|
|
|
+ state.pos = pos
|
|
|
+ end
|
|
|
+ return false
|
|
|
+ end
|
|
|
+
|
|
|
+ local function Err (msg)
|
|
|
+ return g.Cmt (g.Cc (msg) * g.Carg (2), ErrorCall)
|
|
|
+ end
|
|
|
+
|
|
|
+ local SingleLineComment = P"//" * (1 - S"\n\r")^0
|
|
|
+ local MultiLineComment = P"/*" * (1 - P"*/")^0 * P"*/"
|
|
|
+ local Space = (S" \n\r\t" + P"\239\187\191" + SingleLineComment + MultiLineComment)^0
|
|
|
+
|
|
|
+ local PlainChar = 1 - S"\"\\\n\r"
|
|
|
+ local EscapeSequence = (P"\\" * g.C (S"\"\\/bfnrt" + Err "unsupported escape sequence")) / escapechars
|
|
|
+ local HexDigit = R("09", "af", "AF")
|
|
|
+ local function UTF16Surrogate (match, pos, high, low)
|
|
|
+ high, low = tonumber (high, 16), tonumber (low, 16)
|
|
|
+ if 0xD800 <= high and high <= 0xDBff and 0xDC00 <= low and low <= 0xDFFF then
|
|
|
+ return true, unichar ((high - 0xD800) * 0x400 + (low - 0xDC00) + 0x10000)
|
|
|
+ else
|
|
|
+ return false
|
|
|
+ end
|
|
|
+ end
|
|
|
+ local function UTF16BMP (hex)
|
|
|
+ return unichar (tonumber (hex, 16))
|
|
|
+ end
|
|
|
+ local U16Sequence = (P"\\u" * g.C (HexDigit * HexDigit * HexDigit * HexDigit))
|
|
|
+ local UnicodeEscape = g.Cmt (U16Sequence * U16Sequence, UTF16Surrogate) + U16Sequence/UTF16BMP
|
|
|
+ local Char = UnicodeEscape + EscapeSequence + PlainChar
|
|
|
+ local String = P"\"" * g.Cs (Char ^ 0) * (P"\"" + Err "unterminated string")
|
|
|
+ local Integer = P"-"^(-1) * (P"0" + (R"19" * R"09"^0))
|
|
|
+ local Fractal = P"." * R"09"^0
|
|
|
+ local Exponent = (S"eE") * (S"+-")^(-1) * R"09"^1
|
|
|
+ local Number = (Integer * Fractal^(-1) * Exponent^(-1))/str2num
|
|
|
+ local Constant = P"true" * g.Cc (true) + P"false" * g.Cc (false) + P"null" * g.Carg (1)
|
|
|
+ local SimpleValue = Number + String + Constant
|
|
|
+ local ArrayContent, ObjectContent
|
|
|
+
|
|
|
+ -- The functions parsearray and parseobject parse only a single value/pair
|
|
|
+ -- at a time and store them directly to avoid hitting the LPeg limits.
|
|
|
+ local function parsearray (str, pos, nullval, state)
|
|
|
+ local obj, cont
|
|
|
+ local npos
|
|
|
+ local t, nt = {}, 0
|
|
|
+ repeat
|
|
|
+ obj, cont, npos = pegmatch (ArrayContent, str, pos, nullval, state)
|
|
|
+ if not npos then break end
|
|
|
+ pos = npos
|
|
|
+ nt = nt + 1
|
|
|
+ t[nt] = obj
|
|
|
+ until cont == 'last'
|
|
|
+ return pos, setmetatable (t, state.arraymeta)
|
|
|
+ end
|
|
|
+
|
|
|
+ local function parseobject (str, pos, nullval, state)
|
|
|
+ local obj, key, cont
|
|
|
+ local npos
|
|
|
+ local t = {}
|
|
|
+ repeat
|
|
|
+ key, obj, cont, npos = pegmatch (ObjectContent, str, pos, nullval, state)
|
|
|
+ if not npos then break end
|
|
|
+ pos = npos
|
|
|
+ t[key] = obj
|
|
|
+ until cont == 'last'
|
|
|
+ return pos, setmetatable (t, state.objectmeta)
|
|
|
+ end
|
|
|
+
|
|
|
+ local Array = P"[" * g.Cmt (g.Carg(1) * g.Carg(2), parsearray) * Space * (P"]" + Err "']' expected")
|
|
|
+ local Object = P"{" * g.Cmt (g.Carg(1) * g.Carg(2), parseobject) * Space * (P"}" + Err "'}' expected")
|
|
|
+ local Value = Space * (Array + Object + SimpleValue)
|
|
|
+ local ExpectedValue = Value + Space * Err "value expected"
|
|
|
+ ArrayContent = Value * Space * (P"," * g.Cc'cont' + g.Cc'last') * g.Cp()
|
|
|
+ local Pair = g.Cg (Space * String * Space * (P":" + Err "colon expected") * ExpectedValue)
|
|
|
+ ObjectContent = Pair * Space * (P"," * g.Cc'cont' + g.Cc'last') * g.Cp()
|
|
|
+ local DecodeValue = ExpectedValue * g.Cp ()
|
|
|
+
|
|
|
+ function json.decode (str, pos, nullval, ...)
|
|
|
+ local state = {}
|
|
|
+ state.objectmeta, state.arraymeta = optionalmetatables(...)
|
|
|
+ local obj, retpos = pegmatch (DecodeValue, str, pos, nullval, state)
|
|
|
+ if state.msg then
|
|
|
+ return nil, state.pos, state.msg
|
|
|
+ else
|
|
|
+ return obj, retpos
|
|
|
+ end
|
|
|
+ end
|
|
|
+
|
|
|
+ -- use this function only once:
|
|
|
+ json.use_lpeg = function () return json end
|
|
|
+
|
|
|
+ json.using_lpeg = true
|
|
|
+
|
|
|
+ return json -- so you can get the module using json = require "dkjson".use_lpeg()
|
|
|
+end
|
|
|
+
|
|
|
+if always_try_using_lpeg then
|
|
|
+ pcall (json.use_lpeg)
|
|
|
+end
|
|
|
+
|
|
|
+return json
|
|
|
+
|
bjorn
