mirror of
https://github.com/ArchiveTeam/reddit-grab
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1054 lines
34 KiB
Lua
1054 lines
34 KiB
Lua
-- -*- coding: utf-8 -*-
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--
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-- Simple JSON encoding and decoding in pure Lua.
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--
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-- Copyright 2010-2014 Jeffrey Friedl
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-- http://regex.info/blog/
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--
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-- Latest version: http://regex.info/blog/lua/json
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--
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-- This code is released under a Creative Commons CC-BY "Attribution" License:
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-- http://creativecommons.org/licenses/by/3.0/deed.en_US
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--
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-- It can be used for any purpose so long as the copyright notice above,
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-- the web-page links above, and the 'AUTHOR_NOTE' string below are
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-- maintained. Enjoy.
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--
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local VERSION = 20141223.14 -- version history at end of file
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local AUTHOR_NOTE = "-[ JSON.lua package by Jeffrey Friedl (http://regex.info/blog/lua/json) version 20141223.14 ]-"
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--
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-- The 'AUTHOR_NOTE' variable exists so that information about the source
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-- of the package is maintained even in compiled versions. It's also
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-- included in OBJDEF below mostly to quiet warnings about unused variables.
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--
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local OBJDEF = {
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VERSION = VERSION,
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AUTHOR_NOTE = AUTHOR_NOTE,
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}
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--
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-- Simple JSON encoding and decoding in pure Lua.
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-- http://www.json.org/
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--
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--
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-- JSON = assert(loadfile "JSON.lua")() -- one-time load of the routines
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--
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-- local lua_value = JSON:decode(raw_json_text)
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--
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-- local raw_json_text = JSON:encode(lua_table_or_value)
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-- local pretty_json_text = JSON:encode_pretty(lua_table_or_value) -- "pretty printed" version for human readability
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--
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--
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--
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-- DECODING (from a JSON string to a Lua table)
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--
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--
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-- JSON = assert(loadfile "JSON.lua")() -- one-time load of the routines
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--
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-- local lua_value = JSON:decode(raw_json_text)
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--
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-- If the JSON text is for an object or an array, e.g.
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-- { "what": "books", "count": 3 }
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-- or
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-- [ "Larry", "Curly", "Moe" ]
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--
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-- the result is a Lua table, e.g.
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-- { what = "books", count = 3 }
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-- or
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-- { "Larry", "Curly", "Moe" }
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--
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--
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-- The encode and decode routines accept an optional second argument,
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-- "etc", which is not used during encoding or decoding, but upon error
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-- is passed along to error handlers. It can be of any type (including nil).
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--
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--
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--
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-- ERROR HANDLING
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--
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-- With most errors during decoding, this code calls
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--
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-- JSON:onDecodeError(message, text, location, etc)
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--
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-- with a message about the error, and if known, the JSON text being
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-- parsed and the byte count where the problem was discovered. You can
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-- replace the default JSON:onDecodeError() with your own function.
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--
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-- The default onDecodeError() merely augments the message with data
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-- about the text and the location if known (and if a second 'etc'
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-- argument had been provided to decode(), its value is tacked onto the
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-- message as well), and then calls JSON.assert(), which itself defaults
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-- to Lua's built-in assert(), and can also be overridden.
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--
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-- For example, in an Adobe Lightroom plugin, you might use something like
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--
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-- function JSON:onDecodeError(message, text, location, etc)
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-- LrErrors.throwUserError("Internal Error: invalid JSON data")
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-- end
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--
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-- or even just
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--
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-- function JSON.assert(message)
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-- LrErrors.throwUserError("Internal Error: " .. message)
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-- end
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--
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-- If JSON:decode() is passed a nil, this is called instead:
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--
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-- JSON:onDecodeOfNilError(message, nil, nil, etc)
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--
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-- and if JSON:decode() is passed HTML instead of JSON, this is called:
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--
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-- JSON:onDecodeOfHTMLError(message, text, nil, etc)
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--
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-- The use of the fourth 'etc' argument allows stronger coordination
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-- between decoding and error reporting, especially when you provide your
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-- own error-handling routines. Continuing with the the Adobe Lightroom
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-- plugin example:
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--
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-- function JSON:onDecodeError(message, text, location, etc)
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-- local note = "Internal Error: invalid JSON data"
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-- if type(etc) = 'table' and etc.photo then
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-- note = note .. " while processing for " .. etc.photo:getFormattedMetadata('fileName')
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-- end
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-- LrErrors.throwUserError(note)
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-- end
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--
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-- :
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-- :
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--
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-- for i, photo in ipairs(photosToProcess) do
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-- :
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-- :
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-- local data = JSON:decode(someJsonText, { photo = photo })
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-- :
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-- :
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-- end
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--
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--
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--
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--
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--
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-- DECODING AND STRICT TYPES
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--
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-- Because both JSON objects and JSON arrays are converted to Lua tables,
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-- it's not normally possible to tell which original JSON type a
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-- particular Lua table was derived from, or guarantee decode-encode
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-- round-trip equivalency.
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--
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-- However, if you enable strictTypes, e.g.
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--
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-- JSON = assert(loadfile "JSON.lua")() --load the routines
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-- JSON.strictTypes = true
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--
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-- then the Lua table resulting from the decoding of a JSON object or
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-- JSON array is marked via Lua metatable, so that when re-encoded with
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-- JSON:encode() it ends up as the appropriate JSON type.
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--
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-- (This is not the default because other routines may not work well with
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-- tables that have a metatable set, for example, Lightroom API calls.)
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--
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--
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-- ENCODING (from a lua table to a JSON string)
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--
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-- JSON = assert(loadfile "JSON.lua")() -- one-time load of the routines
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--
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-- local raw_json_text = JSON:encode(lua_table_or_value)
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-- local pretty_json_text = JSON:encode_pretty(lua_table_or_value) -- "pretty printed" version for human readability
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-- local custom_pretty = JSON:encode(lua_table_or_value, etc, { pretty = true, indent = "| ", align_keys = false })
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--
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-- On error during encoding, this code calls:
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--
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-- JSON:onEncodeError(message, etc)
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--
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-- which you can override in your local JSON object.
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--
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-- The 'etc' in the error call is the second argument to encode()
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-- and encode_pretty(), or nil if it wasn't provided.
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--
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--
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-- PRETTY-PRINTING
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--
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-- An optional third argument, a table of options, allows a bit of
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-- configuration about how the encoding takes place:
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--
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-- pretty = JSON:encode(val, etc, {
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-- pretty = true, -- if false, no other options matter
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-- indent = " ", -- this provides for a three-space indent per nesting level
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-- align_keys = false, -- see below
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-- })
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--
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-- encode() and encode_pretty() are identical except that encode_pretty()
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-- provides a default options table if none given in the call:
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--
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-- { pretty = true, align_keys = false, indent = " " }
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--
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-- For example, if
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--
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-- JSON:encode(data)
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--
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-- produces:
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--
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-- {"city":"Kyoto","climate":{"avg_temp":16,"humidity":"high","snowfall":"minimal"},"country":"Japan","wards":11}
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--
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-- then
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--
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-- JSON:encode_pretty(data)
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--
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-- produces:
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--
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-- {
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-- "city": "Kyoto",
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-- "climate": {
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-- "avg_temp": 16,
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-- "humidity": "high",
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-- "snowfall": "minimal"
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-- },
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-- "country": "Japan",
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-- "wards": 11
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-- }
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--
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-- The following three lines return identical results:
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-- JSON:encode_pretty(data)
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-- JSON:encode_pretty(data, nil, { pretty = true, align_keys = false, indent = " " })
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-- JSON:encode (data, nil, { pretty = true, align_keys = false, indent = " " })
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--
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-- An example of setting your own indent string:
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--
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-- JSON:encode_pretty(data, nil, { pretty = true, indent = "| " })
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--
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-- produces:
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--
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-- {
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-- | "city": "Kyoto",
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-- | "climate": {
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-- | | "avg_temp": 16,
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-- | | "humidity": "high",
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-- | | "snowfall": "minimal"
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-- | },
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-- | "country": "Japan",
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-- | "wards": 11
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-- }
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--
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-- An example of setting align_keys to true:
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--
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-- JSON:encode_pretty(data, nil, { pretty = true, indent = " ", align_keys = true })
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--
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-- produces:
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--
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-- {
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-- "city": "Kyoto",
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-- "climate": {
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-- "avg_temp": 16,
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-- "humidity": "high",
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-- "snowfall": "minimal"
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-- },
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-- "country": "Japan",
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-- "wards": 11
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-- }
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--
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-- which I must admit is kinda ugly, sorry. This was the default for
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-- encode_pretty() prior to version 20141223.14.
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--
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--
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-- AMBIGUOUS SITUATIONS DURING THE ENCODING
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--
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-- During the encode, if a Lua table being encoded contains both string
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-- and numeric keys, it fits neither JSON's idea of an object, nor its
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-- idea of an array. To get around this, when any string key exists (or
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-- when non-positive numeric keys exist), numeric keys are converted to
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-- strings.
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--
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-- For example,
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-- JSON:encode({ "one", "two", "three", SOMESTRING = "some string" }))
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-- produces the JSON object
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-- {"1":"one","2":"two","3":"three","SOMESTRING":"some string"}
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--
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-- To prohibit this conversion and instead make it an error condition, set
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-- JSON.noKeyConversion = true
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--
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--
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-- SUMMARY OF METHODS YOU CAN OVERRIDE IN YOUR LOCAL LUA JSON OBJECT
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--
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-- assert
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-- onDecodeError
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-- onDecodeOfNilError
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-- onDecodeOfHTMLError
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-- onEncodeError
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--
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-- If you want to create a separate Lua JSON object with its own error handlers,
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-- you can reload JSON.lua or use the :new() method.
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--
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---------------------------------------------------------------------------
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local default_pretty_indent = " "
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local default_pretty_options = { pretty = true, align_keys = false, indent = default_pretty_indent }
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local isArray = { __tostring = function() return "JSON array" end } isArray.__index = isArray
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local isObject = { __tostring = function() return "JSON object" end } isObject.__index = isObject
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function OBJDEF:newArray(tbl)
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return setmetatable(tbl or {}, isArray)
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end
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function OBJDEF:newObject(tbl)
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return setmetatable(tbl or {}, isObject)
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end
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local function unicode_codepoint_as_utf8(codepoint)
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--
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-- codepoint is a number
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--
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if codepoint <= 127 then
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return string.char(codepoint)
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elseif codepoint <= 2047 then
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--
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-- 110yyyxx 10xxxxxx <-- useful notation from http://en.wikipedia.org/wiki/Utf8
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--
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local highpart = math.floor(codepoint / 0x40)
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local lowpart = codepoint - (0x40 * highpart)
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return string.char(0xC0 + highpart,
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0x80 + lowpart)
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elseif codepoint <= 65535 then
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--
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-- 1110yyyy 10yyyyxx 10xxxxxx
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--
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local highpart = math.floor(codepoint / 0x1000)
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local remainder = codepoint - 0x1000 * highpart
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local midpart = math.floor(remainder / 0x40)
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local lowpart = remainder - 0x40 * midpart
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highpart = 0xE0 + highpart
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midpart = 0x80 + midpart
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lowpart = 0x80 + lowpart
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--
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-- Check for an invalid character (thanks Andy R. at Adobe).
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-- See table 3.7, page 93, in http://www.unicode.org/versions/Unicode5.2.0/ch03.pdf#G28070
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--
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if ( highpart == 0xE0 and midpart < 0xA0 ) or
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( highpart == 0xED and midpart > 0x9F ) or
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( highpart == 0xF0 and midpart < 0x90 ) or
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( highpart == 0xF4 and midpart > 0x8F )
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then
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return "?"
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else
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return string.char(highpart,
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midpart,
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lowpart)
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end
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else
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--
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-- 11110zzz 10zzyyyy 10yyyyxx 10xxxxxx
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--
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local highpart = math.floor(codepoint / 0x40000)
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local remainder = codepoint - 0x40000 * highpart
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local midA = math.floor(remainder / 0x1000)
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remainder = remainder - 0x1000 * midA
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local midB = math.floor(remainder / 0x40)
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local lowpart = remainder - 0x40 * midB
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return string.char(0xF0 + highpart,
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0x80 + midA,
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0x80 + midB,
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0x80 + lowpart)
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end
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end
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function OBJDEF:onDecodeError(message, text, location, etc)
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if text then
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if location then
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message = string.format("%s at char %d of: %s", message, location, text)
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else
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message = string.format("%s: %s", message, text)
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end
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end
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if etc ~= nil then
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message = message .. " (" .. OBJDEF:encode(etc) .. ")"
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end
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if self.assert then
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self.assert(false, message)
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else
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assert(false, message)
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end
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end
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OBJDEF.onDecodeOfNilError = OBJDEF.onDecodeError
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OBJDEF.onDecodeOfHTMLError = OBJDEF.onDecodeError
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function OBJDEF:onEncodeError(message, etc)
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if etc ~= nil then
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message = message .. " (" .. OBJDEF:encode(etc) .. ")"
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end
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if self.assert then
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self.assert(false, message)
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else
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assert(false, message)
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end
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end
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local function grok_number(self, text, start, etc)
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--
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-- Grab the integer part
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--
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local integer_part = text:match('^-?[1-9]%d*', start)
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or text:match("^-?0", start)
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if not integer_part then
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self:onDecodeError("expected number", text, start, etc)
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end
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local i = start + integer_part:len()
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--
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-- Grab an optional decimal part
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--
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local decimal_part = text:match('^%.%d+', i) or ""
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i = i + decimal_part:len()
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--
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-- Grab an optional exponential part
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--
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local exponent_part = text:match('^[eE][-+]?%d+', i) or ""
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i = i + exponent_part:len()
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local full_number_text = integer_part .. decimal_part .. exponent_part
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local as_number = tonumber(full_number_text)
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if not as_number then
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self:onDecodeError("bad number", text, start, etc)
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end
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return as_number, i
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end
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local function grok_string(self, text, start, etc)
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if text:sub(start,start) ~= '"' then
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self:onDecodeError("expected string's opening quote", text, start, etc)
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end
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local i = start + 1 -- +1 to bypass the initial quote
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local text_len = text:len()
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local VALUE = ""
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while i <= text_len do
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local c = text:sub(i,i)
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if c == '"' then
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return VALUE, i + 1
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end
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if c ~= '\\' then
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VALUE = VALUE .. c
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i = i + 1
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elseif text:match('^\\b', i) then
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VALUE = VALUE .. "\b"
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i = i + 2
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elseif text:match('^\\f', i) then
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VALUE = VALUE .. "\f"
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i = i + 2
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elseif text:match('^\\n', i) then
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VALUE = VALUE .. "\n"
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i = i + 2
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elseif text:match('^\\r', i) then
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VALUE = VALUE .. "\r"
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i = i + 2
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elseif text:match('^\\t', i) then
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VALUE = VALUE .. "\t"
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i = i + 2
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else
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local hex = text:match('^\\u([0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF])', i)
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if hex then
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i = i + 6 -- bypass what we just read
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-- We have a Unicode codepoint. It could be standalone, or if in the proper range and
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-- followed by another in a specific range, it'll be a two-code surrogate pair.
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local codepoint = tonumber(hex, 16)
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if codepoint >= 0xD800 and codepoint <= 0xDBFF then
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-- it's a hi surrogate... see whether we have a following low
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local lo_surrogate = text:match('^\\u([dD][cdefCDEF][0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF])', i)
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if lo_surrogate then
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i = i + 6 -- bypass the low surrogate we just read
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codepoint = 0x2400 + (codepoint - 0xD800) * 0x400 + tonumber(lo_surrogate, 16)
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else
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-- not a proper low, so we'll just leave the first codepoint as is and spit it out.
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end
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end
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VALUE = VALUE .. unicode_codepoint_as_utf8(codepoint)
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else
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-- just pass through what's escaped
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VALUE = VALUE .. text:match('^\\(.)', i)
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i = i + 2
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end
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end
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end
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self:onDecodeError("unclosed string", text, start, etc)
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end
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local function skip_whitespace(text, start)
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local _, match_end = text:find("^[ \n\r\t]+", start) -- [http://www.ietf.org/rfc/rfc4627.txt] Section 2
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if match_end then
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return match_end + 1
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else
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return start
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end
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end
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local grok_one -- assigned later
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local function grok_object(self, text, start, etc)
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if text:sub(start,start) ~= '{' then
|
|
self:onDecodeError("expected '{'", text, start, etc)
|
|
end
|
|
|
|
local i = skip_whitespace(text, start + 1) -- +1 to skip the '{'
|
|
|
|
local VALUE = self.strictTypes and self:newObject { } or { }
|
|
|
|
if text:sub(i,i) == '}' then
|
|
return VALUE, i + 1
|
|
end
|
|
local text_len = text:len()
|
|
while i <= text_len do
|
|
local key, new_i = grok_string(self, text, i, etc)
|
|
|
|
i = skip_whitespace(text, new_i)
|
|
|
|
if text:sub(i, i) ~= ':' then
|
|
self:onDecodeError("expected colon", text, i, etc)
|
|
end
|
|
|
|
i = skip_whitespace(text, i + 1)
|
|
|
|
local new_val, new_i = grok_one(self, text, i)
|
|
|
|
VALUE[key] = new_val
|
|
|
|
--
|
|
-- Expect now either '}' to end things, or a ',' to allow us to continue.
|
|
--
|
|
i = skip_whitespace(text, new_i)
|
|
|
|
local c = text:sub(i,i)
|
|
|
|
if c == '}' then
|
|
return VALUE, i + 1
|
|
end
|
|
|
|
if text:sub(i, i) ~= ',' then
|
|
self:onDecodeError("expected comma or '}'", text, i, etc)
|
|
end
|
|
|
|
i = skip_whitespace(text, i + 1)
|
|
end
|
|
|
|
self:onDecodeError("unclosed '{'", text, start, etc)
|
|
end
|
|
|
|
local function grok_array(self, text, start, etc)
|
|
if text:sub(start,start) ~= '[' then
|
|
self:onDecodeError("expected '['", text, start, etc)
|
|
end
|
|
|
|
local i = skip_whitespace(text, start + 1) -- +1 to skip the '['
|
|
local VALUE = self.strictTypes and self:newArray { } or { }
|
|
if text:sub(i,i) == ']' then
|
|
return VALUE, i + 1
|
|
end
|
|
|
|
local VALUE_INDEX = 1
|
|
|
|
local text_len = text:len()
|
|
while i <= text_len do
|
|
local val, new_i = grok_one(self, text, i)
|
|
|
|
-- can't table.insert(VALUE, val) here because it's a no-op if val is nil
|
|
VALUE[VALUE_INDEX] = val
|
|
VALUE_INDEX = VALUE_INDEX + 1
|
|
|
|
i = skip_whitespace(text, new_i)
|
|
|
|
--
|
|
-- Expect now either ']' to end things, or a ',' to allow us to continue.
|
|
--
|
|
local c = text:sub(i,i)
|
|
if c == ']' then
|
|
return VALUE, i + 1
|
|
end
|
|
if text:sub(i, i) ~= ',' then
|
|
self:onDecodeError("expected comma or '['", text, i, etc)
|
|
end
|
|
i = skip_whitespace(text, i + 1)
|
|
end
|
|
self:onDecodeError("unclosed '['", text, start, etc)
|
|
end
|
|
|
|
|
|
grok_one = function(self, text, start, etc)
|
|
-- Skip any whitespace
|
|
start = skip_whitespace(text, start)
|
|
|
|
if start > text:len() then
|
|
self:onDecodeError("unexpected end of string", text, nil, etc)
|
|
end
|
|
|
|
if text:find('^"', start) then
|
|
return grok_string(self, text, start, etc)
|
|
|
|
elseif text:find('^[-0123456789 ]', start) then
|
|
return grok_number(self, text, start, etc)
|
|
|
|
elseif text:find('^%{', start) then
|
|
return grok_object(self, text, start, etc)
|
|
|
|
elseif text:find('^%[', start) then
|
|
return grok_array(self, text, start, etc)
|
|
|
|
elseif text:find('^true', start) then
|
|
return true, start + 4
|
|
|
|
elseif text:find('^false', start) then
|
|
return false, start + 5
|
|
|
|
elseif text:find('^null', start) then
|
|
return nil, start + 4
|
|
|
|
else
|
|
self:onDecodeError("can't parse JSON", text, start, etc)
|
|
end
|
|
end
|
|
|
|
function OBJDEF:decode(text, etc)
|
|
if type(self) ~= 'table' or self.__index ~= OBJDEF then
|
|
OBJDEF:onDecodeError("JSON:decode must be called in method format", nil, nil, etc)
|
|
end
|
|
|
|
if text == nil then
|
|
self:onDecodeOfNilError(string.format("nil passed to JSON:decode()"), nil, nil, etc)
|
|
elseif type(text) ~= 'string' then
|
|
self:onDecodeError(string.format("expected string argument to JSON:decode(), got %s", type(text)), nil, nil, etc)
|
|
end
|
|
|
|
if text:match('^%s*$') then
|
|
return nil
|
|
end
|
|
|
|
if text:match('^%s*<') then
|
|
-- Can't be JSON... we'll assume it's HTML
|
|
self:onDecodeOfHTMLError(string.format("html passed to JSON:decode()"), text, nil, etc)
|
|
end
|
|
|
|
--
|
|
-- Ensure that it's not UTF-32 or UTF-16.
|
|
-- Those are perfectly valid encodings for JSON (as per RFC 4627 section 3),
|
|
-- but this package can't handle them.
|
|
--
|
|
if text:sub(1,1):byte() == 0 or (text:len() >= 2 and text:sub(2,2):byte() == 0) then
|
|
self:onDecodeError("JSON package groks only UTF-8, sorry", text, nil, etc)
|
|
end
|
|
|
|
local success, value = pcall(grok_one, self, text, 1, etc)
|
|
|
|
if success then
|
|
return value
|
|
else
|
|
-- if JSON:onDecodeError() didn't abort out of the pcall, we'll have received the error message here as "value", so pass it along as an assert.
|
|
if self.assert then
|
|
self.assert(false, value)
|
|
else
|
|
assert(false, value)
|
|
end
|
|
-- and if we're still here, return a nil and throw the error message on as a second arg
|
|
return nil, value
|
|
end
|
|
end
|
|
|
|
local function backslash_replacement_function(c)
|
|
if c == "\n" then
|
|
return "\\n"
|
|
elseif c == "\r" then
|
|
return "\\r"
|
|
elseif c == "\t" then
|
|
return "\\t"
|
|
elseif c == "\b" then
|
|
return "\\b"
|
|
elseif c == "\f" then
|
|
return "\\f"
|
|
elseif c == '"' then
|
|
return '\\"'
|
|
elseif c == '\\' then
|
|
return '\\\\'
|
|
else
|
|
return string.format("\\u%04x", c:byte())
|
|
end
|
|
end
|
|
|
|
local chars_to_be_escaped_in_JSON_string
|
|
= '['
|
|
.. '"' -- class sub-pattern to match a double quote
|
|
.. '%\\' -- class sub-pattern to match a backslash
|
|
.. '%z' -- class sub-pattern to match a null
|
|
.. '\001' .. '-' .. '\031' -- class sub-pattern to match control characters
|
|
.. ']'
|
|
|
|
local function json_string_literal(value)
|
|
local newval = value:gsub(chars_to_be_escaped_in_JSON_string, backslash_replacement_function)
|
|
return '"' .. newval .. '"'
|
|
end
|
|
|
|
local function object_or_array(self, T, etc)
|
|
--
|
|
-- We need to inspect all the keys... if there are any strings, we'll convert to a JSON
|
|
-- object. If there are only numbers, it's a JSON array.
|
|
--
|
|
-- If we'll be converting to a JSON object, we'll want to sort the keys so that the
|
|
-- end result is deterministic.
|
|
--
|
|
local string_keys = { }
|
|
local number_keys = { }
|
|
local number_keys_must_be_strings = false
|
|
local maximum_number_key
|
|
|
|
for key in pairs(T) do
|
|
if type(key) == 'string' then
|
|
table.insert(string_keys, key)
|
|
elseif type(key) == 'number' then
|
|
table.insert(number_keys, key)
|
|
if key <= 0 or key >= math.huge then
|
|
number_keys_must_be_strings = true
|
|
elseif not maximum_number_key or key > maximum_number_key then
|
|
maximum_number_key = key
|
|
end
|
|
else
|
|
self:onEncodeError("can't encode table with a key of type " .. type(key), etc)
|
|
end
|
|
end
|
|
|
|
if #string_keys == 0 and not number_keys_must_be_strings then
|
|
--
|
|
-- An empty table, or a numeric-only array
|
|
--
|
|
if #number_keys > 0 then
|
|
return nil, maximum_number_key -- an array
|
|
elseif tostring(T) == "JSON array" then
|
|
return nil
|
|
elseif tostring(T) == "JSON object" then
|
|
return { }
|
|
else
|
|
-- have to guess, so we'll pick array, since empty arrays are likely more common than empty objects
|
|
return nil
|
|
end
|
|
end
|
|
|
|
table.sort(string_keys)
|
|
|
|
local map
|
|
if #number_keys > 0 then
|
|
--
|
|
-- If we're here then we have either mixed string/number keys, or numbers inappropriate for a JSON array
|
|
-- It's not ideal, but we'll turn the numbers into strings so that we can at least create a JSON object.
|
|
--
|
|
|
|
if self.noKeyConversion then
|
|
self:onEncodeError("a table with both numeric and string keys could be an object or array; aborting", etc)
|
|
end
|
|
|
|
--
|
|
-- Have to make a shallow copy of the source table so we can remap the numeric keys to be strings
|
|
--
|
|
map = { }
|
|
for key, val in pairs(T) do
|
|
map[key] = val
|
|
end
|
|
|
|
table.sort(number_keys)
|
|
|
|
--
|
|
-- Throw numeric keys in there as strings
|
|
--
|
|
for _, number_key in ipairs(number_keys) do
|
|
local string_key = tostring(number_key)
|
|
if map[string_key] == nil then
|
|
table.insert(string_keys , string_key)
|
|
map[string_key] = T[number_key]
|
|
else
|
|
self:onEncodeError("conflict converting table with mixed-type keys into a JSON object: key " .. number_key .. " exists both as a string and a number.", etc)
|
|
end
|
|
end
|
|
end
|
|
|
|
return string_keys, nil, map
|
|
end
|
|
|
|
--
|
|
-- Encode
|
|
--
|
|
-- 'options' is nil, or a table with possible keys:
|
|
-- pretty -- if true, return a pretty-printed version
|
|
-- indent -- a string (usually of spaces) used to indent each nested level
|
|
-- align_keys -- if true, align all the keys when formatting a table
|
|
--
|
|
local encode_value -- must predeclare because it calls itself
|
|
function encode_value(self, value, parents, etc, options, indent)
|
|
|
|
if value == nil then
|
|
return 'null'
|
|
|
|
elseif type(value) == 'string' then
|
|
return json_string_literal(value)
|
|
|
|
elseif type(value) == 'number' then
|
|
if value ~= value then
|
|
--
|
|
-- NaN (Not a Number).
|
|
-- JSON has no NaN, so we have to fudge the best we can. This should really be a package option.
|
|
--
|
|
return "null"
|
|
elseif value >= math.huge then
|
|
--
|
|
-- Positive infinity. JSON has no INF, so we have to fudge the best we can. This should
|
|
-- really be a package option. Note: at least with some implementations, positive infinity
|
|
-- is both ">= math.huge" and "<= -math.huge", which makes no sense but that's how it is.
|
|
-- Negative infinity is properly "<= -math.huge". So, we must be sure to check the ">="
|
|
-- case first.
|
|
--
|
|
return "1e+9999"
|
|
elseif value <= -math.huge then
|
|
--
|
|
-- Negative infinity.
|
|
-- JSON has no INF, so we have to fudge the best we can. This should really be a package option.
|
|
--
|
|
return "-1e+9999"
|
|
else
|
|
return tostring(value)
|
|
end
|
|
|
|
elseif type(value) == 'boolean' then
|
|
return tostring(value)
|
|
|
|
elseif type(value) ~= 'table' then
|
|
self:onEncodeError("can't convert " .. type(value) .. " to JSON", etc)
|
|
|
|
else
|
|
--
|
|
-- A table to be converted to either a JSON object or array.
|
|
--
|
|
local T = value
|
|
|
|
if type(options) ~= 'table' then
|
|
options = {}
|
|
end
|
|
if type(indent) ~= 'string' then
|
|
indent = ""
|
|
end
|
|
|
|
if parents[T] then
|
|
self:onEncodeError("table " .. tostring(T) .. " is a child of itself", etc)
|
|
else
|
|
parents[T] = true
|
|
end
|
|
|
|
local result_value
|
|
|
|
local object_keys, maximum_number_key, map = object_or_array(self, T, etc)
|
|
if maximum_number_key then
|
|
--
|
|
-- An array...
|
|
--
|
|
local ITEMS = { }
|
|
for i = 1, maximum_number_key do
|
|
table.insert(ITEMS, encode_value(self, T[i], parents, etc, options, indent))
|
|
end
|
|
|
|
if options.pretty then
|
|
result_value = "[ " .. table.concat(ITEMS, ", ") .. " ]"
|
|
else
|
|
result_value = "[" .. table.concat(ITEMS, ",") .. "]"
|
|
end
|
|
|
|
elseif object_keys then
|
|
--
|
|
-- An object
|
|
--
|
|
local TT = map or T
|
|
|
|
if options.pretty then
|
|
|
|
local KEYS = { }
|
|
local max_key_length = 0
|
|
for _, key in ipairs(object_keys) do
|
|
local encoded = encode_value(self, tostring(key), parents, etc, options, indent)
|
|
if options.align_keys then
|
|
max_key_length = math.max(max_key_length, #encoded)
|
|
end
|
|
table.insert(KEYS, encoded)
|
|
end
|
|
local key_indent = indent .. tostring(options.indent or "")
|
|
local subtable_indent = key_indent .. string.rep(" ", max_key_length) .. (options.align_keys and " " or "")
|
|
local FORMAT = "%s%" .. string.format("%d", max_key_length) .. "s: %s"
|
|
|
|
local COMBINED_PARTS = { }
|
|
for i, key in ipairs(object_keys) do
|
|
local encoded_val = encode_value(self, TT[key], parents, etc, options, subtable_indent)
|
|
table.insert(COMBINED_PARTS, string.format(FORMAT, key_indent, KEYS[i], encoded_val))
|
|
end
|
|
result_value = "{\n" .. table.concat(COMBINED_PARTS, ",\n") .. "\n" .. indent .. "}"
|
|
|
|
else
|
|
|
|
local PARTS = { }
|
|
for _, key in ipairs(object_keys) do
|
|
local encoded_val = encode_value(self, TT[key], parents, etc, options, indent)
|
|
local encoded_key = encode_value(self, tostring(key), parents, etc, options, indent)
|
|
table.insert(PARTS, string.format("%s:%s", encoded_key, encoded_val))
|
|
end
|
|
result_value = "{" .. table.concat(PARTS, ",") .. "}"
|
|
|
|
end
|
|
else
|
|
--
|
|
-- An empty array/object... we'll treat it as an array, though it should really be an option
|
|
--
|
|
result_value = "[]"
|
|
end
|
|
|
|
parents[T] = false
|
|
return result_value
|
|
end
|
|
end
|
|
|
|
|
|
function OBJDEF:encode(value, etc, options)
|
|
if type(self) ~= 'table' or self.__index ~= OBJDEF then
|
|
OBJDEF:onEncodeError("JSON:encode must be called in method format", etc)
|
|
end
|
|
return encode_value(self, value, {}, etc, options or nil)
|
|
end
|
|
|
|
function OBJDEF:encode_pretty(value, etc, options)
|
|
if type(self) ~= 'table' or self.__index ~= OBJDEF then
|
|
OBJDEF:onEncodeError("JSON:encode_pretty must be called in method format", etc)
|
|
end
|
|
return encode_value(self, value, {}, etc, options or default_pretty_options)
|
|
end
|
|
|
|
function OBJDEF.__tostring()
|
|
return "JSON encode/decode package"
|
|
end
|
|
|
|
OBJDEF.__index = OBJDEF
|
|
|
|
function OBJDEF:new(args)
|
|
local new = { }
|
|
|
|
if args then
|
|
for key, val in pairs(args) do
|
|
new[key] = val
|
|
end
|
|
end
|
|
|
|
return setmetatable(new, OBJDEF)
|
|
end
|
|
|
|
return OBJDEF:new()
|
|
|
|
--
|
|
-- Version history:
|
|
--
|
|
-- 20141223.14 The encode_pretty() routine produced fine results for small datasets, but isn't really
|
|
-- appropriate for anything large, so with help from Alex Aulbach I've made the encode routines
|
|
-- more flexible, and changed the default encode_pretty() to be more generally useful.
|
|
--
|
|
-- Added a third 'options' argument to the encode() and encode_pretty() routines, to control
|
|
-- how the encoding takes place.
|
|
--
|
|
-- Updated docs to add assert() call to the loadfile() line, just as good practice so that
|
|
-- if there is a problem loading JSON.lua, the appropriate error message will percolate up.
|
|
--
|
|
-- 20140920.13 Put back (in a way that doesn't cause warnings about unused variables) the author string,
|
|
-- so that the source of the package, and its version number, are visible in compiled copies.
|
|
--
|
|
-- 20140911.12 Minor lua cleanup.
|
|
-- Fixed internal reference to 'JSON.noKeyConversion' to reference 'self' instead of 'JSON'.
|
|
-- (Thanks to SmugMug's David Parry for these.)
|
|
--
|
|
-- 20140418.11 JSON nulls embedded within an array were being ignored, such that
|
|
-- ["1",null,null,null,null,null,"seven"],
|
|
-- would return
|
|
-- {1,"seven"}
|
|
-- It's now fixed to properly return
|
|
-- {1, nil, nil, nil, nil, nil, "seven"}
|
|
-- Thanks to "haddock" for catching the error.
|
|
--
|
|
-- 20140116.10 The user's JSON.assert() wasn't always being used. Thanks to "blue" for the heads up.
|
|
--
|
|
-- 20131118.9 Update for Lua 5.3... it seems that tostring(2/1) produces "2.0" instead of "2",
|
|
-- and this caused some problems.
|
|
--
|
|
-- 20131031.8 Unified the code for encode() and encode_pretty(); they had been stupidly separate,
|
|
-- and had of course diverged (encode_pretty didn't get the fixes that encode got, so
|
|
-- sometimes produced incorrect results; thanks to Mattie for the heads up).
|
|
--
|
|
-- Handle encoding tables with non-positive numeric keys (unlikely, but possible).
|
|
--
|
|
-- If a table has both numeric and string keys, or its numeric keys are inappropriate
|
|
-- (such as being non-positive or infinite), the numeric keys are turned into
|
|
-- string keys appropriate for a JSON object. So, as before,
|
|
-- JSON:encode({ "one", "two", "three" })
|
|
-- produces the array
|
|
-- ["one","two","three"]
|
|
-- but now something with mixed key types like
|
|
-- JSON:encode({ "one", "two", "three", SOMESTRING = "some string" }))
|
|
-- instead of throwing an error produces an object:
|
|
-- {"1":"one","2":"two","3":"three","SOMESTRING":"some string"}
|
|
--
|
|
-- To maintain the prior throw-an-error semantics, set
|
|
-- JSON.noKeyConversion = true
|
|
--
|
|
-- 20131004.7 Release under a Creative Commons CC-BY license, which I should have done from day one, sorry.
|
|
--
|
|
-- 20130120.6 Comment update: added a link to the specific page on my blog where this code can
|
|
-- be found, so that folks who come across the code outside of my blog can find updates
|
|
-- more easily.
|
|
--
|
|
-- 20111207.5 Added support for the 'etc' arguments, for better error reporting.
|
|
--
|
|
-- 20110731.4 More feedback from David Kolf on how to make the tests for Nan/Infinity system independent.
|
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--
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-- 20110730.3 Incorporated feedback from David Kolf at http://lua-users.org/wiki/JsonModules:
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--
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-- * When encoding lua for JSON, Sparse numeric arrays are now handled by
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-- spitting out full arrays, such that
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-- JSON:encode({"one", "two", [10] = "ten"})
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-- returns
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-- ["one","two",null,null,null,null,null,null,null,"ten"]
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--
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-- In 20100810.2 and earlier, only up to the first non-null value would have been retained.
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--
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-- * When encoding lua for JSON, numeric value NaN gets spit out as null, and infinity as "1+e9999".
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-- Version 20100810.2 and earlier created invalid JSON in both cases.
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--
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-- * Unicode surrogate pairs are now detected when decoding JSON.
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--
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-- 20100810.2 added some checking to ensure that an invalid Unicode character couldn't leak in to the UTF-8 encoding
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--
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-- 20100731.1 initial public release
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--
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