mirror of
https://github.com/danieleteti/delphimvcframework.git
synced 2024-11-18 01:05:54 +01:00
804 lines
25 KiB
Lua
804 lines
25 KiB
Lua
-- Module options:
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local always_try_using_lpeg = false
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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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David Kolf's JSON module for Lua 5.1/5.2
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========================================
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*Version 2.3*
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In the default configuration this module writes no global values, not even
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the module table. Import it using
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json = require ("dkjson")
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In environments where `require` or a similiar function are not available
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and you cannot receive the return value of the module, you can set the
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option `register_global_module_table` to `true`. The module table will
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then be saved in the global variable with the name given by the option
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`global_module_name`.
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Exported functions and values:
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`json.encode (object [, state])`
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--------------------------------
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Create a string representing the object. `Object` can be a table,
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a string, a number, a boolean, `nil`, `json.null` or any object with
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a function `__tojson` in its metatable. A table can only use strings
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and numbers as keys and its values have to be valid objects as
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well. It raises an error for any invalid data types or reference
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cycles.
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`state` is an optional table with the following fields:
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- `indent`
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When `indent` (a boolean) is set, the created string will contain
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newlines and indentations. Otherwise it will be one long line.
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- `keyorder`
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`keyorder` is an array to specify the ordering of keys in the
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encoded output. If an object has keys which are not in this array
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they are written after the sorted keys.
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- `level`
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This is the initial level of indentation used when `indent` is
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set. For each level two spaces are added. When absent it is set
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to 0.
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- `buffer`
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`buffer` is an array to store the strings for the result so they
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can be concatenated at once. When it isn't given, the encode
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function will create it temporary and will return the
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concatenated result.
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- `bufferlen`
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When `bufferlen` is set, it has to be the index of the last
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element of `buffer`.
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- `tables`
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`tables` is a set to detect reference cycles. It is created
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temporary when absent. Every table that is currently processed
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is used as key, the value is `true`.
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When `state.buffer` was set, the return value will be `true` on
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success. Without `state.buffer` the return value will be a string.
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`json.decode (string [, position [, null]])`
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--------------------------------------------
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Decode `string` starting at `position` or at 1 if `position` was
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omitted.
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`null` is an optional value to be returned for null values. The
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default is `nil`, but you could set it to `json.null` or any other
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value.
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The return values are the object or `nil`, the position of the next
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character that doesn't belong to the object, and in case of errors
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an error message.
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Two metatables are created. Every array or object that is decoded gets
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a metatable with the `__jsontype` field set to either `array` or
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`object`. If you want to provide your own metatables use the syntax
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json.decode (string, position, null, objectmeta, arraymeta)
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To prevent the assigning of metatables pass `nil`:
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json.decode (string, position, null, nil)
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`<metatable>.__jsonorder`
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-------------------------
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`__jsonorder` can overwrite the `keyorder` for a specific table.
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`<metatable>.__jsontype`
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------------------------
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`__jsontype` can be either `"array"` or `"object"`. This value is only
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checked for empty tables. (The default for empty tables is `"array"`).
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`<metatable>.__tojson (self, state)`
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------------------------------------
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You can provide your own `__tojson` function in a metatable. In this
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function you can either add directly to the buffer and return true,
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or you can return a string. On errors nil and a message should be
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returned.
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`json.null`
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-----------
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You can use this value for setting explicit `null` values.
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`json.version`
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--------------
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Set to `"dkjson 2.3"`.
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`json.quotestring (string)`
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---------------------------
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Quote a UTF-8 string and escape critical characters using JSON
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escape sequences. This function is only necessary when you build
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your own `__tojson` functions.
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`json.addnewline (state)`
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-------------------------
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When `state.indent` is set, add a newline to `state.buffer` and spaces
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according to `state.level`.
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LPeg support
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------------
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When the local configuration variable `always_try_using_lpeg` is set,
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this module tries to load LPeg to replace the `decode` function. The
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speed increase is significant. You can get the LPeg module at
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<http://www.inf.puc-rio.br/~roberto/lpeg/>.
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When LPeg couldn't be loaded, the pure Lua functions stay active.
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In case you don't want this module to require LPeg on its own,
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disable the option `always_try_using_lpeg` in the options section at
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the top of the module.
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In this case you can later load LPeg support using
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### `json.use_lpeg ()`
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Require the LPeg module and replace the functions `quotestring` and
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and `decode` with functions that use LPeg patterns.
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This function returns the module table, so you can load the module
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using:
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json = require "dkjson".use_lpeg()
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Alternatively you can use `pcall` so the JSON module still works when
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LPeg isn't found.
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json = require "dkjson"
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pcall (json.use_lpeg)
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### `json.using_lpeg`
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This variable is set to `true` when LPeg was loaded successfully.
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---------------------------------------------------------------------
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Contact
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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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*Copyright (C) 2010-2013 David Heiko Kolf*
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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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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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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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<!-- This documentation can be parsed using Markdown to generate HTML.
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The source code is enclosed in a HTML comment so it won't be displayed
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by browsers, but it should be removed from the final HTML file as
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it isn't a valid HTML comment (and wastes space).
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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 concat = table.concat
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local json = { version = "dkjson 2.3" }
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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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local _ENV = nil -- blocking globals in Lua 5.2
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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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json.null = setmetatable ({}, {
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__tojson = function () return "null" end
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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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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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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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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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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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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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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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local encode2 -- forward declaration
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local function addpair (key, value, prev, indent, level, buffer, buflen, tables, globalorder)
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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)
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end
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encode2 = function (value, indent, level, buffer, buflen, tables, globalorder)
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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 nil, "reference cycle"
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end
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tables[value] = true
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local state = {
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indent = indent, level = level, buffer = buffer,
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bufferlen = buflen, tables = tables, keyorder = globalorder
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}
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local ret, msg = valtojson (value, state)
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if not ret then return nil, msg end
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tables[value] = nil
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buflen = state.bufferlen
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if type (ret) == 'string' then
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buflen = buflen + 1
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buffer[buflen] = ret
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end
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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 = tostring (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 nil, "reference cycle"
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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)
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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)
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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)
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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)
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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 nil, "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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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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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)
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if not ret then
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error (msg, 2)
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elseif oldbuffer then
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state.bufferlen = ret
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return true
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else
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return concat (buffer)
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end
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end
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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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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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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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if strsub (str, pos, pos + 2) == "\239\187\191" then
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-- UTF-8 Byte Order Mark
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pos = pos + 3
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else
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return pos
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end
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end
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end
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local escapechars = {
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["\""] = "\"", ["\\"] = "\\", ["/"] = "/", ["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 = tonumber (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")
|
|
local pegmatch = g.match
|
|
local P, S, R, V = g.P, g.S, g.R, g.V
|
|
|
|
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 Space = (S" \n\r\t" + P"\239\187\191")^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))/tonumber
|
|
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
|
|
|
|
-->
|