1869 lines
		
	
	
		
			68 KiB
		
	
	
	
		
			Lua
		
	
	
	
	
	
			
		
		
	
	
			1869 lines
		
	
	
		
			68 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 2010-2017 Jeffrey Friedl
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| -- http://regex.info/blog/
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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:
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| --    1) the copyright notice above is maintained
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| --    2) the web-page links above are maintained
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| --    3) the 'AUTHOR_NOTE' string below is maintained
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| --
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| local VERSION = '20211016.28' -- 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 20211016.28 ]-"
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| 
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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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| 
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| --
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| -- Simple JSON encoding and decoding in pure Lua.
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| -- JSON definition: 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 DURING DECODE
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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 (and, an 'etc' argument had been
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| --   provided to decode(), its value is tacked onto the message as well),
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| --   and then calls JSON.assert(), which itself defaults to Lua's built-in
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| --   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 'etc' argument allows stronger coordination between
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| --   decoding and error reporting, especially when you provide your own
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| --   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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| --   If the JSON text passed to decode() has trailing garbage (e.g. as with the JSON "[123]xyzzy"),
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| --   the method
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| --
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| --       JSON:onTrailingGarbage(json_text, location, parsed_value, etc)
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| --
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| --   is invoked, where:
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| --
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| --       'json_text' is the original JSON text being parsed,
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| --       'location' is the count of bytes into 'json_text' where the garbage starts (6 in the example),
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| --       'parsed_value' is the Lua result of what was successfully parsed ({123} in the example),
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| --       'etc' is as above.
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| --
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| --   If JSON:onTrailingGarbage() does not abort, it should return the value decode() should return,
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| --   or nil + an error message.
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| --
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| --     local new_value, error_message = JSON:onTrailingGarbage()
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| --
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| --   The default JSON:onTrailingGarbage() simply invokes JSON:onDecodeError("trailing garbage"...),
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| --   but you can have this package ignore trailing garbage via
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| --
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| --      function JSON:onTrailingGarbage(json_text, location, parsed_value, etc)
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| --         return parsed_value
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| --      end
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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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| -- DECODING AND STRICT PARSING
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| --
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| --   If strictParsing is true in your JSON object, or if you set strictParsing as a decode option,
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| --   some kinds of technically-invalid JSON that would normally be accepted are rejected with an error.
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| --
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| --   For example, passing in an empty string
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| --
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| --      JSON:decode("")
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| --
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| --   normally succeeds with a return value of nil, but
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| --
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| --      JSON:decode("", nil, { strictParsing = true })
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| --
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| --   results in an error being raised (onDecodeError is called).
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| --
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| --      JSON.strictParsing = true
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| --      JSON:decode("")
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| --
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| --   achieves the same thing.
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| --
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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. Also see "HANDLING UNSUPPORTED VALUE TYPES" below.
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| --
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| --   The 'etc' in the error call is the second argument to encode() and encode_pretty(), or nil if it wasn't provided.
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| --
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| --
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| --
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| --
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| -- ENCODING OPTIONS
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| --
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| --   An optional third argument, a table of options, can be provided to encode().
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| --
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| --       encode_options =  {
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| --           -- options for making "pretty" human-readable JSON (see "PRETTY-PRINTING" below)
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| --           pretty         = true,   -- turn pretty formatting on
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| --           indent         = "   ",  -- use this indent for each level of an array/object
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| --           align_keys     = false,  -- if true, align the keys in a way that sounds like it should be nice, but is actually ugly
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| --           array_newline  = false,  -- if true, array elements become one to a line rather than inline
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| --           
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| --           -- other output-related options
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| --           null           = "\0",   -- see "ENCODING JSON NULL VALUES" below
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| --           stringsAreUtf8 = false,  -- see "HANDLING UNICODE LINE AND PARAGRAPH SEPARATORS FOR JAVA" below
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| --       }
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| --  
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| --       json_string = JSON:encode(mytable, etc, encode_options)
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| --
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| --
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| --
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| -- For reference, the defaults are:
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| --
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| --           pretty         = false
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| --           null           = nil,
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| --           stringsAreUtf8 = false,
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| --
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| --
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| --
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| -- PRETTY-PRINTING
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| --
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| --   Enabling the 'pretty' encode option helps generate human-readable JSON.
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| --
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| --     pretty = JSON:encode(val, etc, {
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| --                                       pretty = true,
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| --                                       indent = "   ",
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| --                                       align_keys = false,
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| --                                     })
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| --
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| --   encode_pretty() is also provided: it's identical to encode() except
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| --   that encode_pretty() provides a default options table if none given in the call:
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| --
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| --       { pretty = true, indent = "  ", align_keys = false, array_newline = false }
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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 lines all return identical strings:
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| --       JSON:encode_pretty(data)
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| --       JSON:encode_pretty(data, nil, { pretty = true, indent = "  ", align_keys = false, array_newline = false})
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| --       JSON:encode_pretty(data, nil, { pretty = true, indent = "  " })
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| --       JSON:encode       (data, nil, { pretty = true, 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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| --  HANDLING UNICODE LINE AND PARAGRAPH SEPARATORS FOR JAVA
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| --
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| --    If the 'stringsAreUtf8' encode option is set to true, consider Lua strings not as a sequence of bytes,
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| --    but as a sequence of UTF-8 characters.
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| --
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| --    Currently, the only practical effect of setting this option is that Unicode LINE and PARAGRAPH
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| --    separators, if found in a string, are encoded with a JSON escape instead of being dumped as is.
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| --    The JSON is valid either way, but encoding this way, apparently, allows the resulting JSON
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| --    to also be valid Java.
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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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| -- ENCODING JSON NULL VALUES
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| --
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| --   Lua tables completely omit keys whose value is nil, so without special handling there's
 | |
| --   no way to represent JSON object's null value in a Lua table.  For example
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| --      JSON:encode({ username = "admin", password = nil })
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| --
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| --   produces:
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| --
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| --      {"username":"admin"}
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| --
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| --   In order to actually produce
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| --
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| --      {"username":"admin", "password":null}
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| --
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| 
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| --   one can include a string value for a "null" field in the options table passed to encode().... 
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| --   any Lua table entry with that value becomes null in the JSON output:
 | |
| --
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| --      JSON:encode({ username = "admin", password = "xyzzy" }, -- First arg is the Lua table to encode as JSON.
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| --                  nil,                                        -- Second arg is the 'etc' value, ignored here
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| --                  { null = "xyzzy" })                         -- Third arg is th options table
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| --
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| --   produces:
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| --
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| --      {"username":"admin", "password":null}
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| --
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| --   Just be sure to use a string that is otherwise unlikely to appear in your data.
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| --   The string "\0" (a string with one null byte) may well be appropriate for many applications.
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| --
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| --   The "null" options also applies to Lua tables that become JSON arrays.
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| --      JSON:encode({ "one", "two", nil, nil })
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| --
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| --   produces
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| --
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| --      ["one","two"]
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| --
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| --   while
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| --
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| --      NullPlaceholder = "\0"
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| --      encode_options = { null = NullPlaceholder }
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| --      JSON:encode({ "one", "two", NullPlaceholder, NullPlaceholder}, nil, encode_options)
 | |
| --   produces
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| --
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| --      ["one","two",null,null]
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| --
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| --
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| --
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| -- HANDLING LARGE AND/OR PRECISE NUMBERS
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| --
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| --
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| --   Without special handling, numbers in JSON can lose precision in Lua.
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| --   For example:
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| --   
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| --      T = JSON:decode('{  "small":12345, "big":12345678901234567890123456789, "precise":9876.67890123456789012345  }')
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| --
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| --      print("small:   ",  type(T.small),    T.small)
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| --      print("big:     ",  type(T.big),      T.big)
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| --      print("precise: ",  type(T.precise),  T.precise)
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| --   
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| --   produces
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| --   
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| --      small:          number  12345
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| --      big:            number  1.2345678901235e+28
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| --      precise:        number  9876.6789012346
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| --
 | |
| --   Precision is lost with both 'big' and 'precise'.
 | |
| --
 | |
| --   This package offers ways to try to handle this better (for some definitions of "better")...
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| --
 | |
| --   The most precise method is by setting the global:
 | |
| --   
 | |
| --      JSON.decodeNumbersAsObjects = true
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| --   
 | |
| --   When this is set, numeric JSON data is encoded into Lua in a form that preserves the exact
 | |
| --   JSON numeric presentation when re-encoded back out to JSON, or accessed in Lua as a string.
 | |
| --
 | |
| --   This is done by encoding the numeric data with a Lua table/metatable that returns
 | |
| --   the possibly-imprecise numeric form when accessed numerically, but the original precise
 | |
| --   representation when accessed as a string.
 | |
| --
 | |
| --   Consider the example above, with this option turned on:
 | |
| --
 | |
| --      JSON.decodeNumbersAsObjects = true
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| --      
 | |
| --      T = JSON:decode('{  "small":12345, "big":12345678901234567890123456789, "precise":9876.67890123456789012345  }')
 | |
| --
 | |
| --      print("small:   ",  type(T.small),    T.small)
 | |
| --      print("big:     ",  type(T.big),      T.big)
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| --      print("precise: ",  type(T.precise),  T.precise)
 | |
| --   
 | |
| --   This now produces:
 | |
| --   
 | |
| --      small:          table   12345
 | |
| --      big:            table   12345678901234567890123456789
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| --      precise:        table   9876.67890123456789012345
 | |
| --   
 | |
| --   However, within Lua you can still use the values (e.g. T.precise in the example above) in numeric
 | |
| --   contexts. In such cases you'll get the possibly-imprecise numeric version, but in string contexts
 | |
| --   and when the data finds its way to this package's encode() function, the original full-precision
 | |
| --   representation is used.
 | |
| --
 | |
| --   You can force access to the string or numeric version via
 | |
| --        JSON:forceString()
 | |
| --        JSON:forceNumber()
 | |
| --   For example,
 | |
| --        local probably_okay = JSON:forceNumber(T.small) -- 'probably_okay' is a number
 | |
| --
 | |
| --   Code the inspects the JSON-turned-Lua data using type() can run into troubles because what used to
 | |
| --   be a number can now be a table (e.g. as the small/big/precise example above shows). Update these
 | |
| --   situations to use JSON:isNumber(item), which returns nil if the item is neither a number nor one
 | |
| --   of these number objects. If it is either, it returns the number itself. For completeness there's
 | |
| --   also JSON:isString(item).
 | |
| --
 | |
| --   If you want to try to avoid the hassles of this "number as an object" kludge for all but really
 | |
| --   big numbers, you can set JSON.decodeNumbersAsObjects and then also set one or both of
 | |
| --            JSON:decodeIntegerObjectificationLength
 | |
| --            JSON:decodeDecimalObjectificationLength
 | |
| --   They refer to the length of the part of the number before and after a decimal point. If they are
 | |
| --   set and their part is at least that number of digits, objectification occurs. If both are set,
 | |
| --   objectification occurs when either length is met.
 | |
| --
 | |
| --   -----------------------
 | |
| --
 | |
| --   Even without using the JSON.decodeNumbersAsObjects option, you can encode numbers in your Lua
 | |
| --   table that retain high precision upon encoding to JSON, by using the JSON:asNumber() function:
 | |
| --
 | |
| --      T = {
 | |
| --         imprecise =                123456789123456789.123456789123456789,
 | |
| --         precise   = JSON:asNumber("123456789123456789.123456789123456789")
 | |
| --      }
 | |
| --
 | |
| --      print(JSON:encode_pretty(T))
 | |
| --
 | |
| --   This produces:
 | |
| --
 | |
| --      { 
 | |
| --         "precise": 123456789123456789.123456789123456789,
 | |
| --         "imprecise": 1.2345678912346e+17
 | |
| --      }
 | |
| --
 | |
| --
 | |
| --   -----------------------
 | |
| --
 | |
| --   A different way to handle big/precise JSON numbers is to have decode() merely return the exact
 | |
| --   string representation of the number instead of the number itself. This approach might be useful
 | |
| --   when the numbers are merely some kind of opaque object identifier and you want to work with them
 | |
| --   in Lua as strings anyway.
 | |
| --   
 | |
| --   This approach is enabled by setting
 | |
| --
 | |
| --      JSON.decodeIntegerStringificationLength = 10
 | |
| --
 | |
| --   The value is the number of digits (of the integer part of the number) at which to stringify numbers.
 | |
| --   NOTE: this setting is ignored if JSON.decodeNumbersAsObjects is true, as that takes precedence.
 | |
| --
 | |
| --   Consider our previous example with this option set to 10:
 | |
| --
 | |
| --      JSON.decodeIntegerStringificationLength = 10
 | |
| --      
 | |
| --      T = JSON:decode('{  "small":12345, "big":12345678901234567890123456789, "precise":9876.67890123456789012345  }')
 | |
| --
 | |
| --      print("small:   ",  type(T.small),    T.small)
 | |
| --      print("big:     ",  type(T.big),      T.big)
 | |
| --      print("precise: ",  type(T.precise),  T.precise)
 | |
| --
 | |
| --   This produces:
 | |
| --
 | |
| --      small:          number  12345
 | |
| --      big:            string  12345678901234567890123456789
 | |
| --      precise:        number  9876.6789012346
 | |
| --
 | |
| --   The long integer of the 'big' field is at least JSON.decodeIntegerStringificationLength digits
 | |
| --   in length, so it's converted not to a Lua integer but to a Lua string. Using a value of 0 or 1 ensures
 | |
| --   that all JSON numeric data becomes strings in Lua.
 | |
| --
 | |
| --   Note that unlike
 | |
| --      JSON.decodeNumbersAsObjects = true
 | |
| --   this stringification is simple and unintelligent: the JSON number simply becomes a Lua string, and that's the end of it.
 | |
| --   If the string is then converted back to JSON, it's still a string. After running the code above, adding
 | |
| --      print(JSON:encode(T))
 | |
| --   produces
 | |
| --      {"big":"12345678901234567890123456789","precise":9876.6789012346,"small":12345}
 | |
| --   which is unlikely to be desired.
 | |
| --
 | |
| --   There's a comparable option for the length of the decimal part of a number:
 | |
| --
 | |
| --      JSON.decodeDecimalStringificationLength
 | |
| --
 | |
| --   This can be used alone or in conjunction with
 | |
| --
 | |
| --      JSON.decodeIntegerStringificationLength
 | |
| --
 | |
| --   to trip stringification on precise numbers with at least JSON.decodeIntegerStringificationLength digits after
 | |
| --   the decimal point. (Both are ignored if JSON.decodeNumbersAsObjects is true.)
 | |
| --
 | |
| --   This example:
 | |
| --
 | |
| --      JSON.decodeIntegerStringificationLength = 10
 | |
| --      JSON.decodeDecimalStringificationLength =  5
 | |
| --
 | |
| --      T = JSON:decode('{  "small":12345, "big":12345678901234567890123456789, "precise":9876.67890123456789012345  }')
 | |
| --      
 | |
| --      print("small:   ",  type(T.small),    T.small)
 | |
| --      print("big:     ",  type(T.big),      T.big)
 | |
| --      print("precise: ",  type(T.precise),  T.precise)
 | |
| --
 | |
| --  produces:
 | |
| --
 | |
| --      small:          number  12345
 | |
| --      big:            string  12345678901234567890123456789
 | |
| --      precise:        string  9876.67890123456789012345
 | |
| --
 | |
| --
 | |
| --  HANDLING UNSUPPORTED VALUE TYPES
 | |
| --
 | |
| --   Among the encoding errors that might be raised is an attempt to convert a table value that has a type
 | |
| --   that this package hasn't accounted for: a function, userdata, or a thread. You can handle these types as table
 | |
| --   values (but not as table keys) if you supply a JSON:unsupportedTypeEncoder() method along the lines of the
 | |
| --   following example:
 | |
| --        
 | |
| --        function JSON:unsupportedTypeEncoder(value_of_unsupported_type)
 | |
| --           if type(value_of_unsupported_type) == 'function' then
 | |
| --              return "a function value"
 | |
| --           else
 | |
| --              return nil
 | |
| --           end
 | |
| --        end
 | |
| --        
 | |
| --   Your unsupportedTypeEncoder() method is actually called with a bunch of arguments:
 | |
| --
 | |
| --      self:unsupportedTypeEncoder(value, parents, etc, options, indent, for_key)
 | |
| --
 | |
| --   The 'value' is the function, thread, or userdata to be converted to JSON.
 | |
| --
 | |
| --   The 'etc' and 'options' arguments are those passed to the original encode(). The other arguments are
 | |
| --   probably of little interest; see the source code. (Note that 'for_key' is never true, as this function
 | |
| --   is invoked only on table values; table keys of these types still trigger the onEncodeError method.)
 | |
| --
 | |
| --   If your unsupportedTypeEncoder() method returns a string, it's inserted into the JSON as is.
 | |
| --   If it returns nil plus an error message, that error message is passed through to an onEncodeError invocation.
 | |
| --   If it returns only nil, processing falls through to a default onEncodeError invocation.
 | |
| --
 | |
| --   If you want to handle everything in a simple way:
 | |
| --
 | |
| --        function JSON:unsupportedTypeEncoder(value)
 | |
| --           return tostring(value)
 | |
| --        end
 | |
| --
 | |
| --
 | |
| -- SUMMARY OF METHODS YOU CAN OVERRIDE IN YOUR LOCAL LUA JSON OBJECT
 | |
| --
 | |
| --    assert
 | |
| --    onDecodeError
 | |
| --    onDecodeOfNilError
 | |
| --    onDecodeOfHTMLError
 | |
| --    onTrailingGarbage
 | |
| --    onEncodeError
 | |
| --    unsupportedTypeEncoder
 | |
| --
 | |
| --  If you want to create a separate Lua JSON object with its own error handlers,
 | |
| --  you can reload JSON.lua or use the :new() method.
 | |
| --
 | |
| ---------------------------------------------------------------------------
 | |
| 
 | |
| local default_pretty_indent  = "  "
 | |
| local default_pretty_options = { pretty = true, indent = default_pretty_indent, align_keys = false, array_newline = false }
 | |
| 
 | |
| local isArray  = { __tostring = function() return "JSON array"         end }  isArray.__index  = isArray
 | |
| local isObject = { __tostring = function() return "JSON object"        end }  isObject.__index = isObject
 | |
| 
 | |
| function OBJDEF:newArray(tbl)
 | |
|    return setmetatable(tbl or {}, isArray)
 | |
| end
 | |
| 
 | |
| function OBJDEF:newObject(tbl)
 | |
|    return setmetatable(tbl or {}, isObject)
 | |
| end
 | |
| 
 | |
| 
 | |
| 
 | |
| 
 | |
| local function getnum(op)
 | |
|    return type(op) == 'number' and op or op.N
 | |
| end
 | |
| 
 | |
| local isNumber = {
 | |
|    __tostring = function(T)  return T.S        end,
 | |
|    __unm      = function(op) return getnum(op) end,
 | |
| 
 | |
|    __concat   = function(op1, op2) return tostring(op1) .. tostring(op2) end,
 | |
|    __add      = function(op1, op2) return getnum(op1)   +   getnum(op2)  end,
 | |
|    __sub      = function(op1, op2) return getnum(op1)   -   getnum(op2)  end,
 | |
|    __mul      = function(op1, op2) return getnum(op1)   *   getnum(op2)  end,
 | |
|    __div      = function(op1, op2) return getnum(op1)   /   getnum(op2)  end,
 | |
|    __mod      = function(op1, op2) return getnum(op1)   %   getnum(op2)  end,
 | |
|    __pow      = function(op1, op2) return getnum(op1)   ^   getnum(op2)  end,
 | |
|    __lt       = function(op1, op2) return getnum(op1)   <   getnum(op2)  end,
 | |
|    __eq       = function(op1, op2) return getnum(op1)   ==  getnum(op2)  end,
 | |
|    __le       = function(op1, op2) return getnum(op1)   <=  getnum(op2)  end,
 | |
| }
 | |
| isNumber.__index = isNumber
 | |
| 
 | |
| function OBJDEF:asNumber(item)
 | |
| 
 | |
|    if getmetatable(item) == isNumber then
 | |
|       -- it's already a JSON number object.
 | |
|       return item
 | |
|    elseif type(item) == 'table' and type(item.S) == 'string' and type(item.N) == 'number' then
 | |
|       -- it's a number-object table that lost its metatable, so give it one
 | |
|       return setmetatable(item, isNumber)
 | |
|    else
 | |
|       -- the normal situation... given a number or a string representation of a number....
 | |
|       local holder = {
 | |
|          S = tostring(item), -- S is the representation of the number as a string, which remains precise
 | |
|          N = tonumber(item), -- N is the number as a Lua number.
 | |
|       }
 | |
|       return setmetatable(holder, isNumber)
 | |
|    end
 | |
| end
 | |
| 
 | |
| --
 | |
| -- Given an item that might be a normal string or number, or might be an 'isNumber' object defined above,
 | |
| -- return the string version. This shouldn't be needed often because the 'isNumber' object should autoconvert
 | |
| -- to a string in most cases, but it's here to allow it to be forced when needed.
 | |
| --
 | |
| function OBJDEF:forceString(item)
 | |
|    if type(item) == 'table' and type(item.S) == 'string' then
 | |
|       return item.S
 | |
|    else
 | |
|       return tostring(item)
 | |
|    end
 | |
| end
 | |
| 
 | |
| --
 | |
| -- Given an item that might be a normal string or number, or might be an 'isNumber' object defined above,
 | |
| -- return the numeric version.
 | |
| --
 | |
| function OBJDEF:forceNumber(item)
 | |
|    if type(item) == 'table' and type(item.N) == 'number' then
 | |
|       return item.N
 | |
|    else
 | |
|       return tonumber(item)
 | |
|    end
 | |
| end
 | |
| 
 | |
| --
 | |
| -- If the given item is a number, return it. Otherwise, return nil.
 | |
| -- This, this can be used both in a conditional and to access the number when you're not sure its form.
 | |
| --
 | |
| function OBJDEF:isNumber(item)
 | |
|    if type(item) == 'number' then
 | |
|       return item
 | |
|    elseif type(item) == 'table' and type(item.N) == 'number' then
 | |
|       return item.N
 | |
|    else
 | |
|       return nil
 | |
|    end
 | |
| end
 | |
| 
 | |
| function OBJDEF:isString(item)
 | |
|    if type(item) == 'string' then
 | |
|       return item
 | |
|    elseif type(item) == 'table' and type(item.S) == 'string' then
 | |
|       return item.S
 | |
|    else
 | |
|       return nil
 | |
|    end
 | |
| end
 | |
| 
 | |
| 
 | |
| 
 | |
| 
 | |
| --
 | |
| -- Some utf8 routines to deal with the fact that Lua handles only bytes
 | |
| --
 | |
| local function top_three_bits(val)
 | |
|    return math.floor(val / 0x20)
 | |
| end
 | |
| 
 | |
| local function top_four_bits(val)
 | |
|    return math.floor(val / 0x10)
 | |
| end
 | |
| 
 | |
| local function unicode_character_bytecount_based_on_first_byte(first_byte)
 | |
|    local W = string.byte(first_byte)
 | |
|    if W < 0x80 then
 | |
|       return 1
 | |
|    elseif (W == 0xC0) or (W == 0xC1) or (W >= 0x80 and W <= 0xBF) or (W >= 0xF5) then
 | |
|       -- this is an error -- W can't be the start of a utf8 character
 | |
|       return 0
 | |
|    elseif top_three_bits(W) == 0x06 then
 | |
|       return 2
 | |
|    elseif top_four_bits(W) == 0x0E then
 | |
|       return 3
 | |
|    else
 | |
|       return 4
 | |
|    end
 | |
| end
 | |
| 
 | |
| 
 | |
| 
 | |
| local function unicode_codepoint_as_utf8(codepoint)
 | |
|    --
 | |
|    -- codepoint is a number
 | |
|    --
 | |
|    if codepoint <= 127 then
 | |
|       return string.char(codepoint)
 | |
| 
 | |
|    elseif codepoint <= 2047 then
 | |
|       --
 | |
|       -- 110yyyxx 10xxxxxx         <-- useful notation from http://en.wikipedia.org/wiki/Utf8
 | |
|       --
 | |
|       local highpart = math.floor(codepoint / 0x40)
 | |
|       local lowpart  = codepoint - (0x40 * highpart)
 | |
|       return string.char(0xC0 + highpart,
 | |
|                          0x80 + lowpart)
 | |
| 
 | |
|    elseif codepoint <= 65535 then
 | |
|       --
 | |
|       -- 1110yyyy 10yyyyxx 10xxxxxx
 | |
|       --
 | |
|       local highpart  = math.floor(codepoint / 0x1000)
 | |
|       local remainder = codepoint - 0x1000 * highpart
 | |
|       local midpart   = math.floor(remainder / 0x40)
 | |
|       local lowpart   = remainder - 0x40 * midpart
 | |
| 
 | |
|       highpart = 0xE0 + highpart
 | |
|       midpart  = 0x80 + midpart
 | |
|       lowpart  = 0x80 + lowpart
 | |
| 
 | |
|       --
 | |
|       -- Check for an invalid character (thanks Andy R. at Adobe).
 | |
|       -- See table 3.7, page 93, in http://www.unicode.org/versions/Unicode5.2.0/ch03.pdf#G28070
 | |
|       --
 | |
|       if ( highpart == 0xE0 and midpart < 0xA0 ) or
 | |
|          ( highpart == 0xED and midpart > 0x9F ) or
 | |
|          ( highpart == 0xF0 and midpart < 0x90 ) or
 | |
|          ( highpart == 0xF4 and midpart > 0x8F )
 | |
|       then
 | |
|          return "?"
 | |
|       else
 | |
|          return string.char(highpart,
 | |
|                             midpart,
 | |
|                             lowpart)
 | |
|       end
 | |
| 
 | |
|    else
 | |
|       --
 | |
|       -- 11110zzz 10zzyyyy 10yyyyxx 10xxxxxx
 | |
|       --
 | |
|       local highpart  = math.floor(codepoint / 0x40000)
 | |
|       local remainder = codepoint - 0x40000 * highpart
 | |
|       local midA      = math.floor(remainder / 0x1000)
 | |
|       remainder       = remainder - 0x1000 * midA
 | |
|       local midB      = math.floor(remainder / 0x40)
 | |
|       local lowpart   = remainder - 0x40 * midB
 | |
| 
 | |
|       return string.char(0xF0 + highpart,
 | |
|                          0x80 + midA,
 | |
|                          0x80 + midB,
 | |
|                          0x80 + lowpart)
 | |
|    end
 | |
| end
 | |
| 
 | |
| function OBJDEF:onDecodeError(message, text, location, etc)
 | |
|    if text then
 | |
|       if location then
 | |
|          message = string.format("%s at byte %d of: %s", message, location, text)
 | |
|       else
 | |
|          message = string.format("%s: %s", message, text)
 | |
|       end
 | |
|    end
 | |
| 
 | |
|    if etc ~= nil then
 | |
|       message = message .. " (" .. OBJDEF:encode(etc) .. ")"
 | |
|    end
 | |
| 
 | |
|    if self.assert then
 | |
|       self.assert(false, message)
 | |
|    else
 | |
|       assert(false, message)
 | |
|    end
 | |
| end
 | |
| 
 | |
| function OBJDEF:onTrailingGarbage(json_text, location, parsed_value, etc)
 | |
|    return self:onDecodeError("trailing garbage", json_text, location, etc)
 | |
| end
 | |
| 
 | |
| OBJDEF.onDecodeOfNilError  = OBJDEF.onDecodeError
 | |
| OBJDEF.onDecodeOfHTMLError = OBJDEF.onDecodeError
 | |
| 
 | |
| function OBJDEF:onEncodeError(message, etc)
 | |
|    if etc ~= nil then
 | |
|       message = message .. " (" .. OBJDEF:encode(etc) .. ")"
 | |
|    end
 | |
| 
 | |
|    if self.assert then
 | |
|       self.assert(false, message)
 | |
|    else
 | |
|       assert(false, message)
 | |
|    end
 | |
| end
 | |
| 
 | |
| local function grok_number(self, text, start, options)
 | |
|    --
 | |
|    -- Grab the integer part
 | |
|    --
 | |
|    local integer_part = text:match('^-?[1-9]%d*', start)
 | |
|                      or text:match("^-?0",        start)
 | |
| 
 | |
|    if not integer_part then
 | |
|       self:onDecodeError("expected number", text, start, options.etc)
 | |
|       return nil, start -- in case the error method doesn't abort, return something sensible
 | |
|    end
 | |
| 
 | |
|    local i = start + integer_part:len()
 | |
| 
 | |
|    --
 | |
|    -- Grab an optional decimal part
 | |
|    --
 | |
|    local decimal_part = text:match('^%.%d+', i) or ""
 | |
| 
 | |
|    i = i + decimal_part:len()
 | |
| 
 | |
|    --
 | |
|    -- Grab an optional exponential part
 | |
|    --
 | |
|    local exponent_part = text:match('^[eE][-+]?%d+', i) or ""
 | |
| 
 | |
|    i = i + exponent_part:len()
 | |
| 
 | |
|    local full_number_text = integer_part .. decimal_part .. exponent_part
 | |
| 
 | |
|    if options.decodeNumbersAsObjects then
 | |
| 
 | |
|       local objectify = false
 | |
| 
 | |
|       if not options.decodeIntegerObjectificationLength and not options.decodeDecimalObjectificationLength then
 | |
|          -- no options, so objectify
 | |
|          objectify = true
 | |
| 
 | |
|       elseif (options.decodeIntegerObjectificationLength
 | |
|           and
 | |
|          (integer_part:len() >= options.decodeIntegerObjectificationLength or exponent_part:len() > 0))
 | |
| 
 | |
|           or
 | |
|          (options.decodeDecimalObjectificationLength 
 | |
|           and
 | |
|           (decimal_part:len() >= options.decodeDecimalObjectificationLength  or exponent_part:len() > 0))
 | |
|       then
 | |
|          -- have options and they are triggered, so objectify
 | |
|          objectify = true
 | |
|       end
 | |
| 
 | |
|       if objectify then
 | |
|          return OBJDEF:asNumber(full_number_text), i
 | |
|       end
 | |
|       -- else, fall through to try to return as a straight-up number
 | |
| 
 | |
|    else
 | |
| 
 | |
|       -- Not always decoding numbers as objects, so perhaps encode as strings?
 | |
| 
 | |
|       --
 | |
|       -- If we're told to stringify only under certain conditions, so do.
 | |
|       -- We punt a bit when there's an exponent by just stringifying no matter what.
 | |
|       -- I suppose we should really look to see whether the exponent is actually big enough one
 | |
|       -- way or the other to trip stringification, but I'll be lazy about it until someone asks.
 | |
|       --
 | |
|       if (options.decodeIntegerStringificationLength
 | |
|           and
 | |
|          (integer_part:len() >= options.decodeIntegerStringificationLength or exponent_part:len() > 0))
 | |
| 
 | |
|           or
 | |
| 
 | |
|          (options.decodeDecimalStringificationLength 
 | |
|           and
 | |
|           (decimal_part:len() >= options.decodeDecimalStringificationLength or exponent_part:len() > 0))
 | |
|       then
 | |
|          return full_number_text, i -- this returns the exact string representation seen in the original JSON
 | |
|       end
 | |
| 
 | |
|    end
 | |
| 
 | |
| 
 | |
|    local as_number = tonumber(full_number_text)
 | |
| 
 | |
|    if not as_number then
 | |
|       self:onDecodeError("bad number", text, start, options.etc)
 | |
|       return nil, start -- in case the error method doesn't abort, return something sensible
 | |
|    end
 | |
| 
 | |
|    return as_number, i
 | |
| end
 | |
| 
 | |
| 
 | |
| local backslash_escape_conversion = {
 | |
|    ['"'] = '"',
 | |
|    ['/'] = "/",
 | |
|    ['\\'] = "\\",
 | |
|    ['b'] = "\b",
 | |
|    ['f'] = "\f",
 | |
|    ['n'] = "\n",
 | |
|    ['r'] = "\r",
 | |
|    ['t'] = "\t",
 | |
| }
 | |
| 
 | |
| local function grok_string(self, text, start, options)
 | |
| 
 | |
|    if text:sub(start,start) ~= '"' then
 | |
|       self:onDecodeError("expected string's opening quote", text, start, options.etc)
 | |
|       return nil, start -- in case the error method doesn't abort, return something sensible
 | |
|    end
 | |
| 
 | |
|    local i = start + 1 -- +1 to bypass the initial quote
 | |
|    local text_len = text:len()
 | |
|    local VALUE = ""
 | |
|    while i <= text_len do
 | |
|       local c = text:sub(i,i)
 | |
|       if c == '"' then
 | |
|          return VALUE, i + 1
 | |
|       end
 | |
|       if c ~= '\\' then
 | |
|          
 | |
|          -- should grab the next bytes as per the number of bytes for this utf8 character
 | |
|          local byte_count = unicode_character_bytecount_based_on_first_byte(c)
 | |
| 
 | |
|          local next_character
 | |
|          if byte_count == 0 then
 | |
|             self:onDecodeError("non-utf8 sequence", text, i, options.etc)
 | |
|          elseif byte_count == 1 then
 | |
|             if options.strictParsing and string.byte(c) < 0x20 then
 | |
|                self:onDecodeError("Unescaped control character", text, i+1, options.etc)
 | |
|                return nil, start -- in case the error method doesn't abort, return something sensible
 | |
|             end
 | |
|             next_character = c
 | |
|          elseif byte_count == 2 then
 | |
|             next_character = text:match('^(.[\128-\191])', i)
 | |
|          elseif byte_count == 3 then
 | |
|             next_character = text:match('^(.[\128-\191][\128-\191])', i)
 | |
|          elseif byte_count == 4 then
 | |
|             next_character = text:match('^(.[\128-\191][\128-\191][\128-\191])', i)
 | |
|          end
 | |
| 
 | |
|          if not next_character then
 | |
|             self:onDecodeError("incomplete utf8 sequence", text, i, options.etc) 
 | |
|             return nil, i -- in case the error method doesn't abort, return something sensible           
 | |
|          end
 | |
| 
 | |
| 
 | |
|          VALUE = VALUE .. next_character
 | |
|          i = i + byte_count
 | |
| 
 | |
|       else
 | |
|          --
 | |
|          -- We have a backslash escape
 | |
|          --
 | |
|          i = i + 1
 | |
| 
 | |
|          local next_byte = text:match('^(.)', i)
 | |
| 
 | |
|          if next_byte == nil then
 | |
|             -- string ended after the \ 
 | |
|             self:onDecodeError("unfinished \\ escape", text, i, options.etc)
 | |
|             return nil, start -- in case the error method doesn't abort, return something sensible
 | |
|          end
 | |
| 
 | |
|          if backslash_escape_conversion[next_byte] then
 | |
|             VALUE = VALUE .. backslash_escape_conversion[next_byte]
 | |
|             i = i + 1
 | |
|          else
 | |
|             --
 | |
|             -- The only other valid use of \ that remains is in the form of \u####
 | |
|             --
 | |
| 
 | |
|             local hex = text:match('^u([0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF])', i)
 | |
|             if hex then
 | |
|                i = i + 5 -- bypass what we just read
 | |
| 
 | |
|                -- We have a Unicode codepoint. It could be standalone, or if in the proper range and
 | |
|                -- followed by another in a specific range, it'll be a two-code surrogate pair.
 | |
|                local codepoint = tonumber(hex, 16)
 | |
|                if codepoint >= 0xD800 and codepoint <= 0xDBFF then
 | |
|                   -- it's a hi surrogate... see whether we have a following low
 | |
|                   local lo_surrogate = text:match('^\\u([dD][cdefCDEF][0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF])', i)
 | |
|                   if lo_surrogate then
 | |
|                      i = i + 6 -- bypass the low surrogate we just read
 | |
|                      codepoint = 0x2400 + (codepoint - 0xD800) * 0x400 + tonumber(lo_surrogate, 16)
 | |
|                   else
 | |
|                      -- not a proper low, so we'll just leave the first codepoint as is and spit it out.
 | |
|                   end
 | |
|                end
 | |
|                VALUE = VALUE .. unicode_codepoint_as_utf8(codepoint)
 | |
| 
 | |
|             elseif options.strictParsing then
 | |
|                --local next_byte = text:match('^\\(.)', i) printf("NEXT[%s]", next_byte);
 | |
|                self:onDecodeError("illegal use of backslash escape", text, i, options.etc)
 | |
|                return nil, start -- in case the error method doesn't abort, return something sensible
 | |
|             else
 | |
|                local byte_count = unicode_character_bytecount_based_on_first_byte(next_byte)
 | |
|                if byte_count == 0 then
 | |
|                   self:onDecodeError("non-utf8 sequence after backslash escape", text, i, options.etc)
 | |
|                   return nil, start -- in case the error method doesn't abort, return something sensible
 | |
|                end
 | |
| 
 | |
|                local next_character
 | |
|                if byte_count == 1 then
 | |
|                   next_character = next_byte
 | |
|                elseif byte_count == 2 then
 | |
|                   next_character = text:match('^(.[\128-\191])', i)
 | |
|                elseif byte_count == 3 then
 | |
|                   next_character = text:match('^(.[\128-\191][\128-\191])', i)
 | |
|                elseif byte_count == 3 then
 | |
|                   next_character = text:match('^(.[\128-\191][\128-\191][\128-\191])', i)
 | |
|                end
 | |
| 
 | |
|                if next_character == nil then
 | |
|                   -- incomplete utf8 character after escape
 | |
|                   self:onDecodeError("incomplete utf8 sequence after backslash escape", text, i, options.etc)
 | |
|                   return nil, start -- in case the error method doesn't abort, return something sensible
 | |
|                end
 | |
| 
 | |
|                VALUE = VALUE .. next_character
 | |
|                i = i + byte_count
 | |
|             end
 | |
|          end
 | |
|       end
 | |
|    end
 | |
| 
 | |
|    self:onDecodeError("unclosed string", text, start, options.etc)
 | |
|    return nil, start -- in case the error method doesn't abort, return something sensible
 | |
| end
 | |
| 
 | |
| local function skip_whitespace(text, start)
 | |
| 
 | |
|    local _, match_end = text:find("^[ \n\r\t]+", start) -- [ https://datatracker.ietf.org/doc/html/rfc7158#section-2 ]
 | |
|    if match_end then
 | |
|       return match_end + 1
 | |
|    else
 | |
|       return start
 | |
|    end
 | |
| end
 | |
| 
 | |
| local grok_one -- assigned later
 | |
| 
 | |
| local function grok_object(self, text, start, options)
 | |
| 
 | |
|    if text:sub(start,start) ~= '{' then
 | |
|       self:onDecodeError("expected '{'", text, start, options.etc)
 | |
|       return nil, start -- in case the error method doesn't abort, return something sensible
 | |
|    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, options)
 | |
| 
 | |
|       i = skip_whitespace(text, new_i)
 | |
| 
 | |
|       if text:sub(i, i) ~= ':' then
 | |
|          self:onDecodeError("expected colon", text, i, options.etc)
 | |
|          return nil, i -- in case the error method doesn't abort, return something sensible
 | |
|       end
 | |
| 
 | |
|       i = skip_whitespace(text, i + 1)
 | |
| 
 | |
|       local new_val, new_i = grok_one(self, text, i, options)
 | |
| 
 | |
|       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, options.etc)
 | |
|          return nil, i -- in case the error method doesn't abort, return something sensible
 | |
|       end
 | |
| 
 | |
|       i = skip_whitespace(text, i + 1)
 | |
|    end
 | |
| 
 | |
|    self:onDecodeError("unclosed '{'", text, start, options.etc)
 | |
|    return nil, start -- in case the error method doesn't abort, return something sensible
 | |
| end
 | |
| 
 | |
| local function grok_array(self, text, start, options)
 | |
|    if text:sub(start,start) ~= '[' then
 | |
|       self:onDecodeError("expected '['", text, start, options.etc)
 | |
|       return nil, start -- in case the error method doesn't abort, return something sensible
 | |
|    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, options)
 | |
| 
 | |
|       -- 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, options.etc)
 | |
|          return nil, i -- in case the error method doesn't abort, return something sensible
 | |
|       end
 | |
|       i = skip_whitespace(text, i + 1)
 | |
|    end
 | |
|    self:onDecodeError("unclosed '['", text, start, options.etc)
 | |
|    return nil, i -- in case the error method doesn't abort, return something sensible
 | |
| end
 | |
| 
 | |
| 
 | |
| grok_one = function(self, text, start, options)
 | |
|    -- Skip any whitespace
 | |
|    start = skip_whitespace(text, start)
 | |
| 
 | |
|    if start > text:len() then
 | |
|       self:onDecodeError("unexpected end of string", text, nil, options.etc)
 | |
|       return nil, start -- in case the error method doesn't abort, return something sensible
 | |
|    end
 | |
| 
 | |
|    if text:find('^"', start) then
 | |
|       return grok_string(self, text, start, options)
 | |
| 
 | |
|    elseif text:find('^[-0123456789 ]', start) then
 | |
|       return grok_number(self, text, start, options)
 | |
| 
 | |
|    elseif text:find('^%{', start) then
 | |
|       return grok_object(self, text, start, options)
 | |
| 
 | |
|    elseif text:find('^%[', start) then
 | |
|       return grok_array(self, text, start, options)
 | |
| 
 | |
|    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 options.null, start + 4
 | |
| 
 | |
|    else
 | |
|       self:onDecodeError("can't parse JSON", text, start, options.etc)
 | |
|       return nil, 1 -- in case the error method doesn't abort, return something sensible
 | |
|    end
 | |
| end
 | |
| 
 | |
| function OBJDEF:decode(text, etc, options)
 | |
|    --
 | |
|    -- If the user didn't pass in a table of decode options, make an empty one.
 | |
|    --
 | |
|    if type(options) ~= 'table' then
 | |
|       options = {}
 | |
|    end
 | |
| 
 | |
|    --
 | |
|    -- If they passed in an 'etc' argument, stuff it into the options.
 | |
|    -- (If not, any 'etc' field in the options they passed in remains to be used)
 | |
|    --
 | |
|    if etc ~= nil then
 | |
|       options.etc = etc
 | |
|    end
 | |
| 
 | |
| 
 | |
|    --
 | |
|    -- apply global options
 | |
|    --
 | |
|    if options.decodeNumbersAsObjects == nil then
 | |
|       options.decodeNumbersAsObjects = self.decodeNumbersAsObjects
 | |
|    end
 | |
|    if options.decodeIntegerObjectificationLength == nil then
 | |
|       options.decodeIntegerObjectificationLength = self.decodeIntegerObjectificationLength
 | |
|    end
 | |
|    if options.decodeDecimalObjectificationLength == nil then
 | |
|       options.decodeDecimalObjectificationLength = self.decodeDecimalObjectificationLength
 | |
|    end
 | |
|    if options.decodeIntegerStringificationLength == nil then
 | |
|       options.decodeIntegerStringificationLength = self.decodeIntegerStringificationLength
 | |
|    end
 | |
|    if options.decodeDecimalStringificationLength == nil then
 | |
|       options.decodeDecimalStringificationLength = self.decodeDecimalStringificationLength
 | |
|    end
 | |
|    if options.strictParsing == nil then
 | |
|       options.strictParsing = self.strictParsing
 | |
|    end
 | |
| 
 | |
| 
 | |
|    if type(self) ~= 'table' or self.__index ~= OBJDEF then
 | |
|       local error_message = "JSON:decode must be called in method format"
 | |
|       OBJDEF:onDecodeError(error_message, nil, nil, options.etc)
 | |
|       return nil, error_message -- in case the error method doesn't abort, return something sensible
 | |
|    end
 | |
| 
 | |
|    if text == nil then
 | |
|       local error_message = "nil passed to JSON:decode()"
 | |
|       self:onDecodeOfNilError(error_message, nil, nil, options.etc)
 | |
|       return nil, error_message -- in case the error method doesn't abort, return something sensible
 | |
| 
 | |
|    elseif type(text) ~= 'string' then
 | |
|       local error_message = "expected string argument to JSON:decode()"
 | |
|       self:onDecodeError(string.format("%s, got %s", error_message, type(text)), nil, nil, options.etc)
 | |
|       return nil, error_message -- in case the error method doesn't abort, return something sensible
 | |
|    end
 | |
| 
 | |
|    -- If passed an empty string....
 | |
|    if text:match('^%s*$') then
 | |
|       if options.strictParsing then
 | |
|          local error_message = "empty string passed to JSON:decode()"
 | |
|          self:onDecodeOfNilError(error_message, nil, nil, options.etc)
 | |
|          return nil, error_message -- in case the error method doesn't abort, return something sensible
 | |
|       else
 | |
|          -- we'll consider it nothing, but not an error
 | |
|          return nil
 | |
|       end
 | |
|    end
 | |
| 
 | |
|    if text:match('^%s*<') then
 | |
|       -- Can't be JSON... we'll assume it's HTML
 | |
|       local error_message = "HTML passed to JSON:decode()"
 | |
|       self:onDecodeOfHTMLError(error_message, text, nil, options.etc)
 | |
|       return nil, error_message -- in case the error method doesn't abort, return something sensible
 | |
|    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
 | |
|       local error_message = "JSON package groks only UTF-8, sorry"
 | |
|       self:onDecodeError(error_message, text, nil, options.etc)
 | |
|       return nil, error_message -- in case the error method doesn't abort, return something sensible
 | |
|    end
 | |
| 
 | |
| 
 | |
|    --
 | |
|    -- Finally, go parse it
 | |
|    --
 | |
|    local success, value, next_i = pcall(grok_one, self, text, 1, options)
 | |
| 
 | |
|    if success then
 | |
| 
 | |
|       local error_message = nil
 | |
|       if next_i ~= #text + 1 then
 | |
|          -- something's left over after we parsed the first thing.... whitespace is allowed.
 | |
|          next_i = skip_whitespace(text, next_i)
 | |
| 
 | |
|          -- if we have something left over now, it's trailing garbage
 | |
|          if next_i ~= #text + 1 then
 | |
|             value, error_message = self:onTrailingGarbage(text, next_i, value, options.etc)
 | |
|          end
 | |
|       end
 | |
|       return value, error_message
 | |
| 
 | |
|    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.
 | |
|       local error_message = value
 | |
|       if self.assert then
 | |
|          self.assert(false, error_message)
 | |
|       else
 | |
|          assert(false, error_message)
 | |
|       end
 | |
|       -- ...and if we're still here (because the assert didn't throw an error),
 | |
|       -- return a nil and throw the error message on as a second arg
 | |
|       return nil, error_message
 | |
| 
 | |
|    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 '\\\\'
 | |
|    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
 | |
|    ..    '/'    -- class sub-pattern to match a forwardslash
 | |
|    ..    '%z'   -- class sub-pattern to match a null
 | |
|    ..    '\001' .. '-' .. '\031' -- class sub-pattern to match control characters
 | |
|    .. ']'
 | |
| 
 | |
| 
 | |
| local LINE_SEPARATOR_as_utf8      = unicode_codepoint_as_utf8(0x2028)
 | |
| local PARAGRAPH_SEPARATOR_as_utf8 = unicode_codepoint_as_utf8(0x2029)
 | |
| local function json_string_literal(value, options)
 | |
|    local newval = value:gsub(chars_to_be_escaped_in_JSON_string, backslash_replacement_function)
 | |
|    if options.stringsAreUtf8 then
 | |
|       --
 | |
|       -- This feels really ugly to just look into a string for the sequence of bytes that we know to be a particular utf8 character,
 | |
|       -- but utf8 was designed purposefully to make this kind of thing possible. Still, feels dirty.
 | |
|       -- I'd rather decode the byte stream into a character stream, but it's not technically needed so
 | |
|       -- not technically worth it.
 | |
|       --
 | |
|       newval = newval:gsub(LINE_SEPARATOR_as_utf8, '\\u2028'):gsub(PARAGRAPH_SEPARATOR_as_utf8,'\\u2029')
 | |
|    end
 | |
|    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
 | |
|       elseif type(key) == 'boolean' then
 | |
|          table.insert(string_keys, tostring(key))
 | |
|       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. The result is uglier than one might at first imagine.
 | |
| --                      Results are undefined if 'align_keys' is true but 'pretty' is not.
 | |
| --
 | |
| --    array_newline  -- If true, array elements are formatted each to their own line. The default is to all fall inline.
 | |
| --                      Results are undefined if 'array_newline' is true but 'pretty' is not.
 | |
| --
 | |
| --    null           -- If this exists with a string value, table elements with this value are output as JSON null.
 | |
| --
 | |
| --    stringsAreUtf8 -- If true, consider Lua strings not as a sequence of bytes, but as a sequence of UTF-8 characters.
 | |
| --                      (Currently, the only practical effect of setting this option is that Unicode LINE and PARAGRAPH
 | |
| --                       separators, if found in a string, are encoded with a JSON escape instead of as raw UTF-8.
 | |
| --                       The JSON is valid either way, but encoding this way, apparently, allows the resulting JSON
 | |
| --                       to also be valid Java.)
 | |
| --
 | |
| --
 | |
| local function encode_value(self, value, parents, etc, options, indent, for_key)
 | |
| 
 | |
|    --
 | |
|    -- keys in a JSON object can never be null, so we don't even consider options.null when converting a key value
 | |
|    --
 | |
|    if value == nil or (not for_key and options and options.null and value == options.null) then
 | |
|       return 'null'
 | |
| 
 | |
|    elseif type(value) == 'string' then
 | |
|       return json_string_literal(value, options)
 | |
| 
 | |
|    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
 | |
| 
 | |
|       if self.unsupportedTypeEncoder then
 | |
|          local user_value, user_error = self:unsupportedTypeEncoder(value, parents, etc, options, indent, for_key)
 | |
|          -- If the user's handler returns a string, use that. If it returns nil plus an error message, bail with that.
 | |
|          -- If only nil returned, fall through to the default error handler.
 | |
|          if type(user_value) == 'string' then
 | |
|             return user_value
 | |
|          elseif user_value ~= nil then
 | |
|             self:onEncodeError("unsupportedTypeEncoder method returned a " .. type(user_value), etc)
 | |
|          elseif user_error then
 | |
|             self:onEncodeError(tostring(user_error), etc)
 | |
|          end
 | |
|       end
 | |
| 
 | |
|       self:onEncodeError("can't convert " .. type(value) .. " to JSON", etc)
 | |
| 
 | |
|    elseif getmetatable(value) == isNumber then
 | |
|       return tostring(value)
 | |
|    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 key_indent
 | |
|          if options.array_newline then
 | |
|             key_indent = indent .. tostring(options.indent or "")
 | |
|          else
 | |
|             key_indent = indent
 | |
|          end
 | |
| 
 | |
|          local ITEMS = { }
 | |
|          for i = 1, maximum_number_key do
 | |
|             table.insert(ITEMS, encode_value(self, T[i], parents, etc, options, key_indent))
 | |
|          end
 | |
| 
 | |
|          if options.array_newline then
 | |
|             result_value = "[\n" .. key_indent .. table.concat(ITEMS, ",\n" .. key_indent) .. "\n" .. indent .. "]"
 | |
|          elseif 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, true)
 | |
|                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, true)
 | |
|                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
 | |
| 
 | |
| local function top_level_encode(self, value, etc, options)
 | |
|    local val = encode_value(self, value, {}, etc, options)
 | |
|    if val == nil then
 | |
|       --PRIVATE("may need to revert to the previous public verison if I can't figure out what the guy wanted")
 | |
|       return val
 | |
|    else
 | |
|       return val
 | |
|    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
 | |
| 
 | |
|    --
 | |
|    -- If the user didn't pass in a table of decode options, make an empty one.
 | |
|    --
 | |
|    if type(options) ~= 'table' then
 | |
|       options = {}
 | |
|    end
 | |
| 
 | |
|    return top_level_encode(self, value, etc, options)
 | |
| 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
 | |
| 
 | |
|    --
 | |
|    -- If the user didn't pass in a table of decode options, use the default pretty ones
 | |
|    --
 | |
|    if type(options) ~= 'table' then
 | |
|       options = default_pretty_options
 | |
|    end
 | |
| 
 | |
|    return top_level_encode(self, value, etc, 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:
 | |
| --
 | |
| --   20211016.28   Had forgotten to document the strictParsing option.
 | |
| --
 | |
| --   20211015.27   Better handle some edge-case errors [ thank you http://seriot.ch/projects/parsing_json.html ; all tests are now successful ]
 | |
| --
 | |
| --                 Added some semblance of proper UTF8 parsing, and now aborts with an error on ilformatted UTF8.
 | |
| --
 | |
| --                 Added the strictParsing option:
 | |
| --                    Aborts with an error on unknown backslash-escape in strings
 | |
| --                    Aborts on naked control characters in strings
 | |
| --                    Aborts when decode is passed a whitespace-only string
 | |
| --
 | |
| --                 For completeness, when encoding a Lua string into a JSON string, escape a forward slash.
 | |
| --
 | |
| --                 String decoding should be a bit more efficient now.
 | |
| --
 | |
| --   20170927.26   Use option.null in decoding as well. Thanks to Max Sindwani for the bump, and sorry to Oliver Hitz
 | |
| --                 whose first mention of it four years ago was completely missed by me.
 | |
| --
 | |
| --   20170823.25   Added support for JSON:unsupportedTypeEncoder().
 | |
| --                 Thanks to Chronos Phaenon Eosphoros (https://github.com/cpeosphoros) for the idea.
 | |
| --
 | |
| --   20170819.24   Added support for boolean keys in tables.
 | |
| --
 | |
| --   20170416.23   Added the "array_newline" formatting option suggested by yurenchen (http://www.yurenchen.com/)
 | |
| --
 | |
| --   20161128.22   Added:
 | |
| --                   JSON:isString()
 | |
| --                   JSON:isNumber()
 | |
| --                   JSON:decodeIntegerObjectificationLength
 | |
| --                   JSON:decodeDecimalObjectificationLength
 | |
| --
 | |
| --   20161109.21   Oops, had a small boo-boo in the previous update.
 | |
| --
 | |
| --   20161103.20   Used to silently ignore trailing garbage when decoding. Now fails via JSON:onTrailingGarbage()
 | |
| --                 http://seriot.ch/parsing_json.php
 | |
| --
 | |
| --                 Built-in error message about "expected comma or ']'" had mistakenly referred to '['
 | |
| --
 | |
| --                 Updated the built-in error reporting to refer to bytes rather than characters.
 | |
| --
 | |
| --                 The decode() method no longer assumes that error handlers abort.
 | |
| --
 | |
| --                 Made the VERSION string a string instead of a number
 | |
| --
 | |
| 
 | |
| --   20160916.19   Fixed the isNumber.__index assignment (thanks to Jack Taylor)
 | |
| --   
 | |
| --   20160730.18   Added JSON:forceString() and JSON:forceNumber()
 | |
| --
 | |
| --   20160728.17   Added concatenation to the metatable for JSON:asNumber()
 | |
| --
 | |
| --   20160709.16   Could crash if not passed an options table (thanks jarno heikkinen <jarnoh@capturemonkey.com>).
 | |
| --
 | |
| --                 Made JSON:asNumber() a bit more resilient to being passed the results of itself.
 | |
| --
 | |
| --   20160526.15   Added the ability to easily encode null values in JSON, via the new "null" encoding option.
 | |
| --                 (Thanks to Adam B for bringing up the issue.)
 | |
| --
 | |
| --                 Added some support for very large numbers and precise floats via
 | |
| --                    JSON.decodeNumbersAsObjects
 | |
| --                    JSON.decodeIntegerStringificationLength
 | |
| --                    JSON.decodeDecimalStringificationLength
 | |
| --
 | |
| --                 Added the "stringsAreUtf8" encoding option. (Hat tip to http://lua-users.org/wiki/JsonModules )
 | |
| --
 | |
| --   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.
 | |
| --
 | |
| --   20110730.3    Incorporated feedback from David Kolf at http://lua-users.org/wiki/JsonModules:
 | |
| --
 | |
| --                   * When encoding lua for JSON, Sparse numeric arrays are now handled by
 | |
| --                     spitting out full arrays, such that
 | |
| --                        JSON:encode({"one", "two", [10] = "ten"})
 | |
| --                     returns
 | |
| --                        ["one","two",null,null,null,null,null,null,null,"ten"]
 | |
| --
 | |
| --                     In 20100810.2 and earlier, only up to the first non-null value would have been retained.
 | |
| --
 | |
| --                   * When encoding lua for JSON, numeric value NaN gets spit out as null, and infinity as "1+e9999".
 | |
| --                     Version 20100810.2 and earlier created invalid JSON in both cases.
 | |
| --
 | |
| --                   * Unicode surrogate pairs are now detected when decoding JSON.
 | |
| --
 | |
| --   20100810.2    added some checking to ensure that an invalid Unicode character couldn't leak in to the UTF-8 encoding
 | |
| --
 | |
| --   20100731.1    initial public release
 | |
| -- | 
