Module:JSON

- -- Original at https://github.com/rxi/json.lua/blob/master/json.lua -- -- Licensed under the MIT license -- See the bottom of the module for license text - local json = {} local table = require('Module:Table')

- -- Encode - local encode local escape_char_map = { ["\\"] = "\\",	["\""] = "\"",	["\a"] = "a", ["\v"] = "v", ["\b"] = "b", ["\f"] = "f", ["\n"] = "n", ["\r"] = "r", ["\t"] = "t", }

local escape_char_map_inv = { ["/"] = "/" } for k, v in pairs(escape_char_map) do	escape_char_map_inv[v] = k end

local function escape_char(c) return "\\" .. (escape_char_map[c] or string.format("u%04x", c:byte)) end

local function encode_nil(val) return "null" end

local function encode_table(val, stack) local res = {} stack = stack or {}

-- Circular reference? assertFalse(stack[val], "circular reference found", 2)

stack[val] = true local isMixed = false local oldVal = val local types = {} local n = 0 -- Check if table is mixed for k, v in pairs(val) do		n = n+1 local tp = type(k) types[k] = tp

if (tp ~= "number" or (tp == 'number' and k <= 0)) and not isMixed then isMixed = true val = {} break end end -- Change all keys to strings if the table is mixed if isMixed then n = 0 for k, v in pairs(oldVal) do			n = n+1 local tp = types[k] val[tp ~= 'string' and tostring(k) or k] = v		end end if not isMixed then -- Treat as array -- check keys are valid and it is not sparse assertFalse(n ~= #val, 'invalid table: cannot parse sparse arrays', 4) -- Encode for i, v in ipairs(val) do			table.insert(res, encode(v, stack)) end stack[val] = nil return "[" .. table.concat(res, ",") .. "]"

else -- Treat as an object for k, v in pairs(val) do			local tp = type(k) assertTrue(tp == 'string' or tp == 'number', "invalid table: invalid key type, must either be a string or number", 2) table.insert(res, encode(k, stack) .. ":" .. encode(v, stack)) end stack[val] = nil return "{" .. table.concat(res, ",") .. "}"	end end

local function encode_string(val) return '"' .. val:gsub('[%z\1-\31\\"]', escape_char) .. '"' end

local function encode_number(val) -- Check for NaN, -inf and inf assertFalse(val ~= val or val <= -math.huge or val >= math.huge, "unexpected number value '" .. tostring(val) .. "'", 5) return string.format("%.14g", val) end

local type_func_map = { ["nil"] = encode_nil, ["table"] = encode_table, ["string"] = encode_string, ["number"] = encode_number, ["boolean"] = tostring, }

encode = function(val, stack) local t = type(val) local f = type_func_map[t] if f then return f(val, stack) else formattedError("cannot parse value of type %q", 5, t)	end end

function json.encode(val) return (encode(val)) end

--- -- Decode ---

local parse local space_chars = table.Set{ " ", "\t", "\r", "\n" } local delim_chars = table.Set{ " ", "\t", "\r", "\n", "]", "}", "," } local escape_chars = table.Set{ "\\", "/", '"', "b", "f", "n", "r", "t", "u" } local literals = table.Set{ "true", "false", "null" }

local literal_map = { ["true"	] = true, ["false"] = false, ["null"	] = nil, }

local function next_char(str, idx, set, negate) for i = idx, #str do		if set[str:sub(i, i)] ~= negate then return i		end end return #str + 1 end

local function decode_error(str, idx, msg) local line_count = 1 local col_count = 1 for i = 1, idx - 1 do		col_count = col_count + 1 if str:sub(i, i) == "\n" then line_count = line_count + 1 col_count = 1 end end error( string.format("%s at line %d col %d", msg, line_count, col_count) ) end

local function codepoint_to_utf8(n) -- http://scripts.sil.org/cms/scripts/page.php?site_id=nrsi&id=iws-appendixa local f = math.floor if n <= 0x7f then return string.char(n) elseif n <= 0x7ff then return string.char(f(n / 64) + 192, n % 64 + 128) elseif n <= 0xffff then return string.char(f(n / 4096) + 224, f(n % 4096 / 64) + 128, n % 64 + 128) elseif n <= 0x10ffff then return string.char(f(n / 262144) + 240, f(n % 262144 / 4096) + 128,											 f(n % 4096 / 64) + 128, n % 64 + 128) else formattedError("invalid unicode codepoint '%x'", n, 4) end end

local function parse_unicode_escape(s) local n1 = tonumber( s:sub(1, 4),	16 ) local n2 = tonumber( s:sub(7, 10), 16 ) -- Surrogate pair? if n2 then return codepoint_to_utf8((n1 - 0xd800) * 0x400 + (n2 - 0xdc00) + 0x10000) else return codepoint_to_utf8(n1) end end

local function parse_string(str, i)	local res = "" local j = i + 1 local k = j

while j <= #str do		local x = str:byte(j)

if x < 32 then decode_error(str, j, "control character in string")

elseif x == 92 then -- `\`: Escape res = res .. str:sub(k, j - 1) j = j + 1 local c = str:sub(j, j)			if c == "u" then local hex = str:match("^[dD][89aAbB]%x%x\\u%x%x%x%x", j + 1) or str:match("^%x%x%x%x", j + 1) or decode_error(str, j - 1, "invalid unicode escape in string") res = res .. parse_unicode_escape(hex) j = j + #hex else if not escape_chars[c] then decode_error(str, j - 1, "invalid escape char '" .. c .. "' in string") end res = res .. escape_char_map_inv[c] end k = j + 1

elseif x == 34 then -- `"`: End of string			res = res .. str:sub(k, j - 1)			return res, j + 1		end

j = j + 1 end decode_error(str, i, "expected closing quote for string") end

local function parse_number(str, i)	local x = next_char(str, i, delim_chars) local s = str:sub(i, x - 1) local n = tonumber(s) if not n then decode_error(str, i, "invalid number '" .. s .. "'") end return n, x end

local function parse_literal(str, i)	local x = next_char(str, i, delim_chars) local word = str:sub(i, x - 1) if not literals[word] then decode_error(str, i, "invalid literal '" .. word .. "'") end return literal_map[word], x end

local function parse_array(str, i)	local res = {} local n = 1 i = i + 1 while 1 do		local x		i = next_char(str, i, space_chars, true) -- Empty / end of array? if str:sub(i, i) == "]" then i = i + 1 break end -- Read token x, i = parse(str, i)		res[n] = x		n = n + 1 -- Next token i = next_char(str, i, space_chars, true) local chr = str:sub(i, i)		i = i + 1 if chr == "]" then break end if chr ~= "," then decode_error(str, i, "expected ']' or ','") end end return res, i end

local function parse_object(str, i)	local res = {} i = i + 1 while 1 do		local key, val i = next_char(str, i, space_chars, true) -- Empty / end of object? if str:sub(i, i) == "}" then i = i + 1 break end -- Read key if str:sub(i, i) ~= '"' then			decode_error(str, i, "expected string for key")		end		key, i = parse(str, i)		-- Read ':' delimiter		i = next_char(str, i, space_chars, true)		if str:sub(i, i) ~= ":" then			decode_error(str, i, "expected ':' after key")		end		i = next_char(str, i + 1, space_chars, true)		-- Read value		val, i = parse(str, i)		-- Set		res[key] = val		-- Next token		i = next_char(str, i, space_chars, true)		local chr = str:sub(i, i)		i = i + 1		if chr == "}" then break end		if chr ~= "," then decode_error(str, i, "expected '}' or ','") end	end	return res, i end

local char_func_map = { ['"'] = parse_string,	["0"] = parse_number,	["1"] = parse_number,	["2"] = parse_number,	["3"] = parse_number,	["4"] = parse_number,	["5"] = parse_number,	["6"] = parse_number,	["7"] = parse_number,	["8"] = parse_number,	["9"] = parse_number,	["-"] = parse_number,	["t"] = parse_literal,	["f"] = parse_literal,	["n"] = parse_literal,	["["] = parse_array,	["{"] = parse_object, }

parse = function(str, idx) local chr = str:sub(idx, idx) local f = char_func_map[chr] if f then return f(str, idx) end decode_error(str, idx, "unexpected character '" .. chr .. "'") end

function json.decode(str) checkType(1, str, 'string') local res, idx = parse(str, next_char(str, 1, space_chars, true)) idx = next_char(str, idx, space_chars, true) if idx <= #str then decode_error(str, idx, "trailing garbage") end return res end

return json

-- Begin License text - -- Copyright (c) 2020 rxi -- -- Permission is hereby granted, free of charge, to any person obtaining a copy of -- this software and associated documentation files (the "Software"), to deal in -- the Software without restriction, including without limitation the rights to -- use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies -- of the Software, and to permit persons to whom the Software is furnished to do -- so, subject to the following conditions: -- -- The above copyright notice and this permission notice shall be included in all -- copies or substantial portions of the Software. -- -- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR -- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, -- FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE -- AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER -- LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, -- OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE -- SOFTWARE. -