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Merge pull request #2 from ntavish/master

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update to version 2.5
This commit is contained in:
Peter Drahoš 2015-03-04 10:57:29 +01:00
commit e72ba0c9f5
6 changed files with 459 additions and 198 deletions
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2
dist.info
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@ -1,7 +1,7 @@
--- This file is part of LuaDist project --- This file is part of LuaDist project
name = "dkjson" name = "dkjson"
version = "2.4" version = "2.5"
desc = "dkjson is a module for encoding and decoding JSON data. It supports UTF-8." desc = "dkjson is a module for encoding and decoding JSON data. It supports UTF-8."
author = "David Kolf" author = "David Kolf"

30
dkjson-2.5-2.rockspec Normal file
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@ -0,0 +1,30 @@
package = "dkjson"
version = "2.5-2"
source = {
url = "http://dkolf.de/src/dkjson-lua.fsl/tarball/dkjson-2.5.tar.gz?uuid=release_2_5",
file = "dkjson-2.5.tar.gz"
}
description = {
summary = "David Kolf's JSON module for Lua",
detailed = [[
dkjson is a module for encoding and decoding JSON data. It supports UTF-8.
JSON (JavaScript Object Notation) is a format for serializing data based
on the syntax for JavaScript data structures.
dkjson is written in Lua without any dependencies, but
when LPeg is available dkjson uses it to speed up decoding.
]],
homepage = "http://dkolf.de/src/dkjson-lua.fsl/",
license = "MIT/X11"
}
dependencies = {
"lua >= 5.1, < 5.4"
}
build = {
type = "builtin",
modules = {
dkjson = "dkjson.lua"
}
}

265
dkjson.lua
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@ -1,178 +1,23 @@
-- Module options: -- Module options:
local always_try_using_lpeg = true local always_try_using_lpeg = true
local register_global_module_table = false local register_global_module_table = false
local global_module_name = 'json' local global_module_name = 'json'
--[==[ --[==[
David Kolf's JSON module for Lua 5.1/5.2 David Kolf's JSON module for Lua 5.1/5.2
========================================
*Version 2.4* Version 2.5
In the default configuration this module writes no global values, not even
the module table. Import it using
json = require ("dkjson") For the documentation see the corresponding readme.txt or visit
<http://dkolf.de/src/dkjson-lua.fsl/>.
In environments where `require` or a similiar function are not available
and you cannot receive the return value of the module, you can set the
option `register_global_module_table` to `true`. The module table will
then be saved in the global variable with the name given by the option
`global_module_name`.
Exported functions and values:
`json.encode (object [, state])`
--------------------------------
Create a string representing the object. `Object` can be a table,
a string, a number, a boolean, `nil`, `json.null` or any object with
a function `__tojson` in its metatable. A table can only use strings
and numbers as keys and its values have to be valid objects as
well. It raises an error for any invalid data types or reference
cycles.
`state` is an optional table with the following fields:
- `indent`
When `indent` (a boolean) is set, the created string will contain
newlines and indentations. Otherwise it will be one long line.
- `keyorder`
`keyorder` is an array to specify the ordering of keys in the
encoded output. If an object has keys which are not in this array
they are written after the sorted keys.
- `level`
This is the initial level of indentation used when `indent` is
set. For each level two spaces are added. When absent it is set
to 0.
- `buffer`
`buffer` is an array to store the strings for the result so they
can be concatenated at once. When it isn't given, the encode
function will create it temporary and will return the
concatenated result.
- `bufferlen`
When `bufferlen` is set, it has to be the index of the last
element of `buffer`.
- `tables`
`tables` is a set to detect reference cycles. It is created
temporary when absent. Every table that is currently processed
is used as key, the value is `true`.
When `state.buffer` was set, the return value will be `true` on
success. Without `state.buffer` the return value will be a string.
`json.decode (string [, position [, null]])`
--------------------------------------------
Decode `string` starting at `position` or at 1 if `position` was
omitted.
`null` is an optional value to be returned for null values. The
default is `nil`, but you could set it to `json.null` or any other
value.
The return values are the object or `nil`, the position of the next
character that doesn't belong to the object, and in case of errors
an error message.
Two metatables are created. Every array or object that is decoded gets
a metatable with the `__jsontype` field set to either `array` or
`object`. If you want to provide your own metatables use the syntax
json.decode (string, position, null, objectmeta, arraymeta)
To prevent the assigning of metatables pass `nil`:
json.decode (string, position, null, nil)
`<metatable>.__jsonorder`
-------------------------
`__jsonorder` can overwrite the `keyorder` for a specific table.
`<metatable>.__jsontype`
------------------------
`__jsontype` can be either `"array"` or `"object"`. This value is only
checked for empty tables. (The default for empty tables is `"array"`).
`<metatable>.__tojson (self, state)`
------------------------------------
You can provide your own `__tojson` function in a metatable. In this
function you can either add directly to the buffer and return true,
or you can return a string. On errors nil and a message should be
returned.
`json.null`
-----------
You can use this value for setting explicit `null` values.
`json.version`
--------------
Set to `"dkjson 2.4"`.
`json.quotestring (string)`
---------------------------
Quote a UTF-8 string and escape critical characters using JSON
escape sequences. This function is only necessary when you build
your own `__tojson` functions.
`json.addnewline (state)`
-------------------------
When `state.indent` is set, add a newline to `state.buffer` and spaces
according to `state.level`.
LPeg support
------------
When the local configuration variable `always_try_using_lpeg` is set,
this module tries to load LPeg to replace the `decode` function. The
speed increase is significant. You can get the LPeg module at
<http://www.inf.puc-rio.br/~roberto/lpeg/>.
When LPeg couldn't be loaded, the pure Lua functions stay active.
In case you don't want this module to require LPeg on its own,
disable the option `always_try_using_lpeg` in the options section at
the top of the module.
In this case you can later load LPeg support using
### `json.use_lpeg ()`
Require the LPeg module and replace the functions `quotestring` and
and `decode` with functions that use LPeg patterns.
This function returns the module table, so you can load the module
using:
json = require "dkjson".use_lpeg()
Alternatively you can use `pcall` so the JSON module still works when
LPeg isn't found.
json = require "dkjson"
pcall (json.use_lpeg)
### `json.using_lpeg`
This variable is set to `true` when LPeg was loaded successfully.
---------------------------------------------------------------------
Contact
-------
You can contact the author by sending an e-mail to 'david' at the You can contact the author by sending an e-mail to 'david' at the
domain 'dkolf.de'. domain 'dkolf.de'.
---------------------------------------------------------------------
*Copyright (C) 2010-2013 David Heiko Kolf* Copyright (C) 2010-2014 David Heiko Kolf
Permission is hereby granted, free of charge, to any person obtaining Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the a copy of this software and associated documentation files (the
@ -194,13 +39,7 @@ ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE. SOFTWARE.
<!-- This documentation can be parsed using Markdown to generate HTML. --]==]
The source code is enclosed in a HTML comment so it won't be displayed
by browsers, but it should be removed from the final HTML file as
it isn't a valid HTML comment (and wastes space).
-->
<!--]==]
-- global dependencies: -- global dependencies:
local pairs, type, tostring, tonumber, getmetatable, setmetatable, rawset = local pairs, type, tostring, tonumber, getmetatable, setmetatable, rawset =
@ -213,7 +52,7 @@ local strrep, gsub, strsub, strbyte, strchar, strfind, strlen, strformat =
local strmatch = string.match local strmatch = string.match
local concat = table.concat local concat = table.concat
local json = { version = "dkjson 2.4" } local json = { version = "dkjson 2.5" }
if register_global_module_table then if register_global_module_table then
_G[global_module_name] = json _G[global_module_name] = json
@ -368,7 +207,7 @@ end
local encode2 -- forward declaration local encode2 -- forward declaration
local function addpair (key, value, prev, indent, level, buffer, buflen, tables, globalorder) local function addpair (key, value, prev, indent, level, buffer, buflen, tables, globalorder, state)
local kt = type (key) local kt = type (key)
if kt ~= 'string' and kt ~= 'number' then if kt ~= 'string' and kt ~= 'number' then
return nil, "type '" .. kt .. "' is not supported as a key by JSON." return nil, "type '" .. kt .. "' is not supported as a key by JSON."
@ -382,31 +221,50 @@ local function addpair (key, value, prev, indent, level, buffer, buflen, tables,
end end
buffer[buflen+1] = quotestring (key) buffer[buflen+1] = quotestring (key)
buffer[buflen+2] = ":" buffer[buflen+2] = ":"
return encode2 (value, indent, level, buffer, buflen + 2, tables, globalorder) return encode2 (value, indent, level, buffer, buflen + 2, tables, globalorder, state)
end end
encode2 = function (value, indent, level, buffer, buflen, tables, globalorder) local function appendcustom(res, buffer, state)
local buflen = state.bufferlen
if type (res) == 'string' then
buflen = buflen + 1
buffer[buflen] = res
end
return buflen
end
local function exception(reason, value, state, buffer, buflen, defaultmessage)
defaultmessage = defaultmessage or reason
local handler = state.exception
if not handler then
return nil, defaultmessage
else
state.bufferlen = buflen
local ret, msg = handler (reason, value, state, defaultmessage)
if not ret then return nil, msg or defaultmessage end
return appendcustom(ret, buffer, state)
end
end
function json.encodeexception(reason, value, state, defaultmessage)
return quotestring("<" .. defaultmessage .. ">")
end
encode2 = function (value, indent, level, buffer, buflen, tables, globalorder, state)
local valtype = type (value) local valtype = type (value)
local valmeta = getmetatable (value) local valmeta = getmetatable (value)
valmeta = type (valmeta) == 'table' and valmeta -- only tables valmeta = type (valmeta) == 'table' and valmeta -- only tables
local valtojson = valmeta and valmeta.__tojson local valtojson = valmeta and valmeta.__tojson
if valtojson then if valtojson then
if tables[value] then if tables[value] then
return nil, "reference cycle" return exception('reference cycle', value, state, buffer, buflen)
end end
tables[value] = true tables[value] = true
local state = { state.bufferlen = buflen
indent = indent, level = level, buffer = buffer,
bufferlen = buflen, tables = tables, keyorder = globalorder
}
local ret, msg = valtojson (value, state) local ret, msg = valtojson (value, state)
if not ret then return nil, msg end if not ret then return exception('custom encoder failed', value, state, buffer, buflen, msg) end
tables[value] = nil tables[value] = nil
buflen = state.bufferlen buflen = appendcustom(ret, buffer, state)
if type (ret) == 'string' then
buflen = buflen + 1
buffer[buflen] = ret
end
elseif value == nil then elseif value == nil then
buflen = buflen + 1 buflen = buflen + 1
buffer[buflen] = "null" buffer[buflen] = "null"
@ -428,7 +286,7 @@ encode2 = function (value, indent, level, buffer, buflen, tables, globalorder)
buffer[buflen] = quotestring (value) buffer[buflen] = quotestring (value)
elseif valtype == 'table' then elseif valtype == 'table' then
if tables[value] then if tables[value] then
return nil, "reference cycle" return exception('reference cycle', value, state, buffer, buflen)
end end
tables[value] = true tables[value] = true
level = level + 1 level = level + 1
@ -441,7 +299,7 @@ encode2 = function (value, indent, level, buffer, buflen, tables, globalorder)
buflen = buflen + 1 buflen = buflen + 1
buffer[buflen] = "[" buffer[buflen] = "["
for i = 1, n do for i = 1, n do
buflen, msg = encode2 (value[i], indent, level, buffer, buflen, tables, globalorder) buflen, msg = encode2 (value[i], indent, level, buffer, buflen, tables, globalorder, state)
if not buflen then return nil, msg end if not buflen then return nil, msg end
if i < n then if i < n then
buflen = buflen + 1 buflen = buflen + 1
@ -463,20 +321,20 @@ encode2 = function (value, indent, level, buffer, buflen, tables, globalorder)
local v = value[k] local v = value[k]
if v then if v then
used[k] = true used[k] = true
buflen, msg = addpair (k, v, prev, indent, level, buffer, buflen, tables, globalorder) buflen, msg = addpair (k, v, prev, indent, level, buffer, buflen, tables, globalorder, state)
prev = true -- add a seperator before the next element prev = true -- add a seperator before the next element
end end
end end
for k,v in pairs (value) do for k,v in pairs (value) do
if not used[k] then if not used[k] then
buflen, msg = addpair (k, v, prev, indent, level, buffer, buflen, tables, globalorder) buflen, msg = addpair (k, v, prev, indent, level, buffer, buflen, tables, globalorder, state)
if not buflen then return nil, msg end if not buflen then return nil, msg end
prev = true -- add a seperator before the next element prev = true -- add a seperator before the next element
end end
end end
else -- unordered else -- unordered
for k,v in pairs (value) do for k,v in pairs (value) do
buflen, msg = addpair (k, v, prev, indent, level, buffer, buflen, tables, globalorder) buflen, msg = addpair (k, v, prev, indent, level, buffer, buflen, tables, globalorder, state)
if not buflen then return nil, msg end if not buflen then return nil, msg end
prev = true -- add a seperator before the next element prev = true -- add a seperator before the next element
end end
@ -489,7 +347,8 @@ encode2 = function (value, indent, level, buffer, buflen, tables, globalorder)
end end
tables[value] = nil tables[value] = nil
else else
return nil, "type '" .. valtype .. "' is not supported by JSON." return exception ('unsupported type', value, state, buffer, buflen,
"type '" .. valtype .. "' is not supported by JSON.")
end end
return buflen return buflen
end end
@ -498,15 +357,18 @@ function json.encode (value, state)
state = state or {} state = state or {}
local oldbuffer = state.buffer local oldbuffer = state.buffer
local buffer = oldbuffer or {} local buffer = oldbuffer or {}
state.buffer = buffer
updatedecpoint() updatedecpoint()
local ret, msg = encode2 (value, state.indent, state.level or 0, local ret, msg = encode2 (value, state.indent, state.level or 0,
buffer, state.bufferlen or 0, state.tables or {}, state.keyorder) buffer, state.bufferlen or 0, state.tables or {}, state.keyorder, state)
if not ret then if not ret then
error (msg, 2) error (msg, 2)
elseif oldbuffer then elseif oldbuffer == buffer then
state.bufferlen = ret state.bufferlen = ret
return true return true
else else
state.bufferlen = nil
state.buffer = nil
return concat (buffer) return concat (buffer)
end end
end end
@ -534,9 +396,17 @@ local function scanwhite (str, pos)
while true do while true do
pos = strfind (str, "%S", pos) pos = strfind (str, "%S", pos)
if not pos then return nil end if not pos then return nil end
if strsub (str, pos, pos + 2) == "\239\187\191" then local sub2 = strsub (str, pos, pos + 1)
if sub2 == "\239\187" and strsub (str, pos + 2, pos + 2) == "\191" then
-- UTF-8 Byte Order Mark -- UTF-8 Byte Order Mark
pos = pos + 3 pos = pos + 3
elseif sub2 == "//" then
pos = strfind (str, "[\n\r]", pos + 2)
if not pos then return nil end
elseif sub2 == "/*" then
pos = strfind (str, "*/", pos + 2)
if not pos then return nil end
pos = pos + 2
else else
return pos return pos
end end
@ -749,7 +619,9 @@ function json.use_lpeg ()
return g.Cmt (g.Cc (msg) * g.Carg (2), ErrorCall) return g.Cmt (g.Cc (msg) * g.Carg (2), ErrorCall)
end end
local Space = (S" \n\r\t" + P"\239\187\191")^0 local SingleLineComment = P"//" * (1 - S"\n\r")^0
local MultiLineComment = P"/*" * (1 - P"*/")^0 * P"*/"
local Space = (S" \n\r\t" + P"\239\187\191" + SingleLineComment + MultiLineComment)^0
local PlainChar = 1 - S"\"\\\n\r" local PlainChar = 1 - S"\"\\\n\r"
local EscapeSequence = (P"\\" * g.C (S"\"\\/bfnrt" + Err "unsupported escape sequence")) / escapechars local EscapeSequence = (P"\\" * g.C (S"\"\\/bfnrt" + Err "unsupported escape sequence")) / escapechars
@ -840,4 +712,3 @@ end
return json return json
-->

141
jsontest.lua
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@ -12,6 +12,7 @@ local test_module, opt = ... -- command line argument
--local test_module = 'nm-json' --local test_module = 'nm-json'
--local test_module = 'sb-json' --local test_module = 'sb-json'
--local test_module = 'th-json' --local test_module = 'th-json'
test_module = test_module or 'dkjson'
--local opt = "esc" -- Test which characters in the BMP get escaped and whether this is correct --local opt = "esc" -- Test which characters in the BMP get escaped and whether this is correct
--local opt = "esc_full" -- Full range from 0 to 0x10ffff --local opt = "esc_full" -- Full range from 0 to 0x10ffff
@ -209,6 +210,122 @@ else
print("In locale 0.5 isn't converted into valid JSON:", x) print("In locale 0.5 isn't converted into valid JSON:", x)
end end
end) end)
-- special tests for dkjson:
if test_module == 'dkjson' then
do -- encode a function
local why, value, exstate
local state = {
exception = function (w, v, s)
why, value, exstate = w, v, s
return "\"demo\""
end
}
local encfunction = function () end
r, x = pcall(dkencode, { encfunction }, state )
if not r then
print("encoding a function with exception handler raises an error:", x)
else
if x ~= "[\"demo\"]" then
print("expected to see output of exception handler for type exception, but got", x)
end
if why ~= "unsupported type" then
print("expected exception reason to be 'unsupported type' for type exception")
end
if value ~= encfunction then
print("expected to recieve value for type exception")
end
if exstate ~= state then
print("expected to recieve state for type exception")
end
end
r, x = pcall(dkencode, { function () end }, {
exception = function (w, v, s)
return nil, "demo"
end
})
if r or x ~= "demo" then
print("expected custom error for type exception, but got:", r, x)
end
r, x = pcall(dkencode, { function () end }, {
exception = function (w, v, s)
return nil
end
})
if r or x ~= "type 'function' is not supported by JSON." then
print("expected default error for type exception, but got:", r, x)
end
end
do -- encode a reference cycle
local why, value, exstate
local state = {
exception = function (w, v, s)
why, value, exstate = w, v, s
return "\"demo\""
end
}
local a = {}
a[1] = a
r, x = pcall(dkencode, a, state )
if not r then
print("encoding a reference cycle with exception handler raises an error:", x)
else
if x ~= "[\"demo\"]" then
print("expected to see output of exception handler for reference cycle exception, but got", x)
end
if why ~= "reference cycle" then
print("expected exception reason to be 'reference cycle' for reference cycle exception")
end
if value ~= a then
print("expected to recieve value for reference cycle exception")
end
if exstate ~= state then
print("expected to recieve state for reference cycle exception")
end
end
end
do -- example exception handler
r = dkencode(function () end, { exception = require "dkjson".encodeexception })
if r ~= [["<type 'function' is not supported by JSON.>"]] then
print("expected the exception encoder to encode default error message, but got", r)
end
end
do -- test state buffer for custom __tojson function
local origstate = {}
local usedstate, usedbuffer, usedbufferlen
dkencode({ setmetatable({}, {
__tojson = function(self, state)
usedstate = state
usedbuffer = state.buffer
usedbufferlen = state.bufferlen
return true
end
}) }, origstate)
if usedstate ~= origstate then print("expected tojson-function to recieve the original state") end
if type(usedbuffer) ~= 'table' or #usedbuffer < 1 then print("expected buffer in tojson-function to be an array") end
if usedbufferlen ~= 1 then print("expected bufferlen in tojson-function to be 1, but got "..tostring(usedbufferlen)) end
end
do -- do not keep buffer and bufferlen when they were not present initially
local origstate = {}
dkencode(setmetatable({}, {__tojson = function() return true end}), origstate)
if origstate.buffer ~= nil then print("expected buffer to be reset to nil") end
if origstate.bufferlen ~= nil then print("expected bufferlen to be reset to nil") end
end
do -- keep buffer and update bufferlen when they were present initially
local origbuffer = {}
local origstate = { buffer = origbuffer }
dkencode(true, origstate)
if origstate.buffer ~= origbuffer then print("expected original buffer to remain") end
if origstate.bufferlen ~= 1 then print("expected bufferlen to be updated") end
end
end
end end
if not decode then if not decode then
@ -318,6 +435,30 @@ else
if p ~= 4 or type(m) ~= 'string' or not m:find("at line 2, column 2$") then if p ~= 4 or type(m) ~= 'string' or not m:find("at line 2, column 2$") then
print (("Invalid location: position=%d, message=%q"):format(p,m)) print (("Invalid location: position=%d, message=%q"):format(p,m))
end end
do -- single line comments
local x, p, m = dkdecode [[
{"test://" // comment // --?
: [ // continues
0] //
}
]]
if type(x) ~= 'table' or type(x["test://"]) ~= 'table' or x["test://"][1] ~= 0 then
print("could not decode a string with single line comments: "..tostring(m))
end
end
do -- multi line comments
local x, p, m = dkdecode [[
{"test:/*"/**//*
hi! this is a comment
*/ : [/** / **/ 0]
}
]]
if type(x) ~= 'table' or type(x["test:/*"]) ~= 'table' or x["test:/*"][1] ~= 0 then
print("could not decode a string with multi line comments: "..tostring(m))
end
end
end end
end end

211
readme.txt Normal file
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@ -0,0 +1,211 @@
David Kolf's JSON module for Lua 5.1/5.2
========================================
*Version 2.5*
In the default configuration this module writes no global values, not even
the module table. Import it using
json = require ("dkjson")
In environments where `require` or a similiar function are not available
and you cannot receive the return value of the module, you can set the
option `register_global_module_table` to `true`. The module table will
then be saved in the global variable with the name given by the option
`global_module_name`.
Exported functions and values:
`json.encode (object [, state])`
--------------------------------
Create a string representing the object. `Object` can be a table,
a string, a number, a boolean, `nil`, `json.null` or any object with
a function `__tojson` in its metatable. A table can only use strings
and numbers as keys and its values have to be valid objects as
well. It raises an error for any invalid data types or reference
cycles.
`state` is an optional table with the following fields:
- `indent`
When `indent` (a boolean) is set, the created string will contain
newlines and indentations. Otherwise it will be one long line.
- `keyorder`
`keyorder` is an array to specify the ordering of keys in the
encoded output. If an object has keys which are not in this array
they are written after the sorted keys.
- `level`
This is the initial level of indentation used when `indent` is
set. For each level two spaces are added. When absent it is set
to 0.
- `buffer`
`buffer` is an array to store the strings for the result so they
can be concatenated at once. When it isn't given, the encode
function will create it temporary and will return the
concatenated result.
- `bufferlen`
When `bufferlen` is set, it has to be the index of the last
element of `buffer`.
- `tables`
`tables` is a set to detect reference cycles. It is created
temporary when absent. Every table that is currently processed
is used as key, the value is `true`.
- `exception`
When `exception` is given, it will be called whenever the encoder
cannot encode a given value.
The parameters are `reason`, `value`, `state` and `defaultmessage`.
`reason` is either `"reference cycle"`, `"custom encoder failed"` or
`"unsupported type"`. `value` is the original value that caused the
exception, `state` is this state table, `defaultmessage` is the message
of the error that would usually be raised.
You can either return `true` and add directly to the buffer or you can
return the string directly. To keep raising an error return `nil` and
the desired error message.
An example implementation for an exception function is given in
`json.encodeexception`.
When `state.buffer` was set, the return value will be `true` on
success. Without `state.buffer` the return value will be a string.
`json.decode (string [, position [, null]])`
--------------------------------------------
Decode `string` starting at `position` or at 1 if `position` was
omitted.
`null` is an optional value to be returned for null values. The
default is `nil`, but you could set it to `json.null` or any other
value.
The return values are the object or `nil`, the position of the next
character that doesn't belong to the object, and in case of errors
an error message.
Two metatables are created. Every array or object that is decoded gets
a metatable with the `__jsontype` field set to either `array` or
`object`. If you want to provide your own metatables use the syntax
json.decode (string, position, null, objectmeta, arraymeta)
To prevent the assigning of metatables pass `nil`:
json.decode (string, position, null, nil)
`<metatable>.__jsonorder`
-------------------------
`__jsonorder` can overwrite the `keyorder` for a specific table.
`<metatable>.__jsontype`
------------------------
`__jsontype` can be either `"array"` or `"object"`. This value is only
checked for empty tables. (The default for empty tables is `"array"`).
`<metatable>.__tojson (self, state)`
------------------------------------
You can provide your own `__tojson` function in a metatable. In this
function you can either add directly to the buffer and return true,
or you can return a string. On errors nil and a message should be
returned.
`json.null`
-----------
You can use this value for setting explicit `null` values.
`json.version`
--------------
Set to `"dkjson 2.5"`.
`json.quotestring (string)`
---------------------------
Quote a UTF-8 string and escape critical characters using JSON
escape sequences. This function is only necessary when you build
your own `__tojson` functions.
`json.addnewline (state)`
-------------------------
When `state.indent` is set, add a newline to `state.buffer` and spaces
according to `state.level`.
`json.encodeexception (reason, value, state, defaultmessage)`
-------------------------------------------------------------
This function can be used as value to the `exception` option. Instead of
raising an error this function encodes the error message as a string. This
can help to debug malformed input data.
x = json.encode(value, { exception = json.encodeexception })
LPeg support
------------
When the local configuration variable `always_try_using_lpeg` is set,
this module tries to load LPeg to replace the `decode` function. The
speed increase is significant. You can get the LPeg module at
<http://www.inf.puc-rio.br/~roberto/lpeg/>.
When LPeg couldn't be loaded, the pure Lua functions stay active.
In case you don't want this module to require LPeg on its own,
disable the option `always_try_using_lpeg` in the options section at
the top of the module.
In this case you can later load LPeg support using
### `json.use_lpeg ()`
Require the LPeg module and replace the functions `quotestring` and
and `decode` with functions that use LPeg patterns.
This function returns the module table, so you can load the module
using:
json = require "dkjson".use_lpeg()
Alternatively you can use `pcall` so the JSON module still works when
LPeg isn't found.
json = require "dkjson"
pcall (json.use_lpeg)
### `json.using_lpeg`
This variable is set to `true` when LPeg was loaded successfully.
---------------------------------------------------------------------
Contact
-------
You can contact the author by sending an e-mail to 'david' at the
domain 'dkolf.de'.
---------------------------------------------------------------------
*Copyright (C) 2010-2014 David Heiko Kolf*
Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:
The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

8
versions.txt
View File

@ -1,3 +1,11 @@
Version 2.5 (2014-04-28)
===========
Changes since version 2.4:
* Added customizable exception handling.
* Decode input that contains JavaScript comments.
Version 2.4 (2013-09-28) Version 2.4 (2013-09-28)
=========== ===========