inspect.lua

local inspect ={
  _VERSION = 'inspect.lua 3.1.0',
  _URL     = 'http://github.com/kikito/inspect.lua',
  _DESCRIPTION = 'human-readable representations of tables',
  _LICENSE = [[
    MIT LICENSE

    Copyright (c) 2013 Enrique García Cota

    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.
  ]]
}

local tostring = tostring

inspect.KEY       = setmetatable({}, {__tostring = function() return 'inspect.KEY' end})
inspect.METATABLE = setmetatable({}, {__tostring = function() return 'inspect.METATABLE' end})

-- Apostrophizes the string if it has quotes, but not aphostrophes
-- Otherwise, it returns a regular quoted string
local function smartQuote(str)
  if str:match('"') and not str:match("'") then
    return "'" .. str .. "'"
  end
  return '"' .. str:gsub('"', '\\"') .. '"'
end

-- \a => '\\a', \0 => '\\0', 31 => '\31'
local shortControlCharEscapes = {
  ["\a"] = "\\a",  ["\b"] = "\\b", ["\f"] = "\\f", ["\n"] = "\\n",
  ["\r"] = "\\r",  ["\t"] = "\\t", ["\v"] = "\\v"
}
local longControlCharEscapes = {} -- \a => nil, \0 => \000, 31 => \031
for i=0, 31 do
  local ch = string.char(i)
  if not shortControlCharEscapes[ch] then
    shortControlCharEscapes[ch] = "\\"..i
    longControlCharEscapes[ch]  = string.format("\\%03d", i)
  end
end

local function escape(str)
  return (str:gsub("\\", "\\\\")
             :gsub("(%c)%f[0-9]", longControlCharEscapes)
             :gsub("%c", shortControlCharEscapes))
end

local function isIdentifier(str)
  return type(str) == 'string' and str:match( "^[_%a][_%a%d]*$" )
end

local function isSequenceKey(k, sequenceLength)
  return type(k) == 'number'
     and 1 <= k
     and k <= sequenceLength
     and math.floor(k) == k
end

local defaultTypeOrders = {
  ['number']   = 1, ['boolean']  = 2, ['string'] = 3, ['table'] = 4,
  ['function'] = 5, ['userdata'] = 6, ['thread'] = 7
}

local function sortKeys(a, b)
  local ta, tb = type(a), type(b)

  -- strings and numbers are sorted numerically/alphabetically
  if ta == tb and (ta == 'string' or ta == 'number') then return a < b end

  local dta, dtb = defaultTypeOrders[ta], defaultTypeOrders[tb]
  -- Two default types are compared according to the defaultTypeOrders table
  if dta and dtb then return defaultTypeOrders[ta] < defaultTypeOrders[tb]
  elseif dta     then return true  -- default types before custom ones
  elseif dtb     then return false -- custom types after default ones
  end

  -- custom types are sorted out alphabetically
  return ta < tb
end

-- For implementation reasons, the behavior of rawlen & # is "undefined" when
-- tables aren't pure sequences. So we implement our own # operator.
local function getSequenceLength(t)
  local len = 1
  local v = rawget(t,len)
  while v ~= nil do
    len = len + 1
    v = rawget(t,len)
  end
  return len - 1
end

local function getNonSequentialKeys(t)
  local keys = {}
  local sequenceLength = getSequenceLength(t)
  for k,_ in pairs(t) do
    if not isSequenceKey(k, sequenceLength) then table.insert(keys, k) end
  end
  table.sort(keys, sortKeys)
  return keys, sequenceLength
end

local function getToStringResultSafely(t, mt)
  local __tostring = type(mt) == 'table' and rawget(mt, '__tostring')
  local str, ok
  if type(__tostring) == 'function' then
    ok, str = pcall(__tostring, t)
    str = ok and str or 'error: ' .. tostring(str)
  end
  if type(str) == 'string' and #str > 0 then return str end
end

local function countTableAppearances(t, tableAppearances)
  tableAppearances = tableAppearances or {}

  if type(t) == 'table' then
    if not tableAppearances[t] then
      tableAppearances[t] = 1
      for k,v in pairs(t) do
        countTableAppearances(k, tableAppearances)
        countTableAppearances(v, tableAppearances)
      end
      countTableAppearances(getmetatable(t), tableAppearances)
    else
      tableAppearances[t] = tableAppearances[t] + 1
    end
  end

  return tableAppearances
end

local copySequence = function(s)
  local copy, len = {}, #s
  for i=1, len do copy[i] = s[i] end
  return copy, len
end

local function makePath(path, ...)
  local keys = {...}
  local newPath, len = copySequence(path)
  for i=1, #keys do
    newPath[len + i] = keys[i]
  end
  return newPath
end

local function processRecursive(process, item, path, visited)

    if item == nil then return nil end
    if visited[item] then return visited[item] end

    local processed = process(item, path)
    if type(processed) == 'table' then
      local processedCopy = {}
      visited[item] = processedCopy
      local processedKey

      for k,v in pairs(processed) do
        processedKey = processRecursive(process, k, makePath(path, k, inspect.KEY), visited)
        if processedKey ~= nil then
          processedCopy[processedKey] = processRecursive(process, v, makePath(path, processedKey), visited)
        end
      end

      local mt  = processRecursive(process, getmetatable(processed), makePath(path, inspect.METATABLE), visited)
      setmetatable(processedCopy, mt)
      processed = processedCopy
    end
    return processed
end



-------------------------------------------------------------------

local Inspector = {}
local Inspector_mt = {__index = Inspector}

function Inspector:puts(...)
  local args   = {...}
  local buffer = self.buffer
  local len    = #buffer
  for i=1, #args do
    len = len + 1
    buffer[len] = args[i]
  end
end

function Inspector:down(f)
  self.level = self.level + 1
  f()
  self.level = self.level - 1
end

function Inspector:tabify()
  self:puts(self.newline, string.rep(self.indent, self.level))
end

function Inspector:alreadyVisited(v)
  return self.ids[v] ~= nil
end

function Inspector:getId(v)
  local id = self.ids[v]
  if not id then
    local tv = type(v)
    id              = (self.maxIds[tv] or 0) + 1
    self.maxIds[tv] = id
    self.ids[v]     = id
  end
  return tostring(id)
end

function Inspector:putKey(k)
  if isIdentifier(k) then return self:puts(k) end
  self:puts("[")
  self:putValue(k)
  self:puts("]")
end

function Inspector:putTable(t)
  if t == inspect.KEY or t == inspect.METATABLE then
    self:puts(tostring(t))
  elseif self:alreadyVisited(t) then
    self:puts('<table ', self:getId(t), '>')
  elseif self.level >= self.depth then
    self:puts('{...}')
  else
    if self.tableAppearances[t] > 1 then self:puts('<', self:getId(t), '>') end

    local nonSequentialKeys, sequenceLength = getNonSequentialKeys(t)
    local mt                = getmetatable(t)
    local toStringResult    = getToStringResultSafely(t, mt)

    self:puts('{')
    self:down(function()
      if toStringResult then
        self:puts(' -- ', escape(toStringResult))
        if sequenceLength >= 1 then self:tabify() end
      end

      local count = 0
      for i=1, sequenceLength do
        if count > 0 then self:puts(',') end
        self:puts(' ')
        self:putValue(t[i])
        count = count + 1
      end

      for _,k in ipairs(nonSequentialKeys) do
        if count > 0 then self:puts(',') end
        self:tabify()
        self:putKey(k)
        self:puts(' = ')
        self:putValue(t[k])
        count = count + 1
      end

      if mt then
        if count > 0 then self:puts(',') end
        self:tabify()
        self:puts('<metatable> = ')
        self:putValue(mt)
      end
    end)

    if #nonSequentialKeys > 0 or mt then -- result is multi-lined. Justify closing }
      self:tabify()
    elseif sequenceLength > 0 then -- array tables have one extra space before closing }
      self:puts(' ')
    end

    self:puts('}')
  end
end

function Inspector:putValue(v)
  local tv = type(v)

  if tv == 'string' then
    self:puts(smartQuote(escape(v)))
  elseif tv == 'number' or tv == 'boolean' or tv == 'nil' then
    self:puts(tostring(v))
  elseif tv == 'table' then
    self:putTable(v)
  else
    self:puts('<',tv,' ',self:getId(v),'>')
  end
end

-------------------------------------------------------------------

function inspect.inspect(root, options)
  options       = options or {}

  local depth   = options.depth   or math.huge
  local newline = options.newline or '\n'
  local indent  = options.indent  or '  '
  local process = options.process

  if process then
    root = processRecursive(process, root, {}, {})
  end

  local inspector = setmetatable({
    depth            = depth,
    level            = 0,
    buffer           = {},
    ids              = {},
    maxIds           = {},
    newline          = newline,
    indent           = indent,
    tableAppearances = countTableAppearances(root)
  }, Inspector_mt)

  inspector:putValue(root)

  return table.concat(inspector.buffer)
end

setmetatable(inspect, { __call = function(_, ...) return inspect.inspect(...) end })

return inspect

json.lua

-----------------------------------------------------------------------------
-- JSON4Lua: JSON encoding / decoding support for the Lua language.
-- json Module.
-- Author: Craig Mason-Jones
-- Homepage: http://github.com/craigmj/json4lua/
-- Version: 1.0.0
-- This module is released under the MIT License (MIT).
-- Please see LICENCE.txt for details.
--
-- USAGE:
-- This module exposes two functions:
--   json.encode(o)
--     Returns the table / string / boolean / number / nil / json.null value as a JSON-encoded string.
--   json.decode(json_string)
--     Returns a Lua object populated with the data encoded in the JSON string json_string.
--
-- REQUIREMENTS:
--   compat-5.1 if using Lua 5.0
--
-- CHANGELOG
--   0.9.20 Introduction of local Lua functions for private functions (removed _ function prefix). 
--          Fixed Lua 5.1 compatibility issues.
--   		Introduced json.null to have null values in associative arrays.
--          json.encode() performance improvement (more than 50%) through table.concat rather than ..
--          Introduced decode ability to ignore /**/ comments in the JSON string.
--   0.9.10 Fix to array encoding / decoding to correctly manage nil/null values in arrays.
-----------------------------------------------------------------------------

-----------------------------------------------------------------------------
-- Module declaration
-----------------------------------------------------------------------------
local json = {}             -- Public namespace
local json_private = {}     -- Private namespace

-- Public constants                                                            
json.EMPTY_ARRAY={}                                                           
json.EMPTY_OBJECT={}

-- Public functions

-- Private functions
local decode_scanArray
local decode_scanComment
local decode_scanConstant
local decode_scanNumber
local decode_scanObject
local decode_scanString
local decode_scanWhitespace
local encodeString
local isArray
local isEncodable

-----------------------------------------------------------------------------
-- PUBLIC FUNCTIONS
-----------------------------------------------------------------------------
--- Encodes an arbitrary Lua object / variable.
-- @param v The Lua object / variable to be JSON encoded.
-- @return String containing the JSON encoding in internal Lua string format (i.e. not unicode)
function json.encode (v)
  -- Handle nil values
  if v==nil then
    return "null"
  end
  
  local vtype = type(v)

  -- Handle strings
  if vtype=='string' then    
    return '"' .. json_private.encodeString(v) .. '"'	    -- Need to handle encoding in string
  end
  
  -- Handle booleans
  if vtype=='number' or vtype=='boolean' then
    return tostring(v)
  end
  
  -- Handle tables
  if vtype=='table' then
    local rval = {}
    -- Consider arrays separately
    local bArray, maxCount = isArray(v)
    if bArray then
      for i = 1,maxCount do
        table.insert(rval, json.encode(v[i]))
      end
    else	-- An object, not an array
      for i,j in pairs(v) do
        if isEncodable(i) and isEncodable(j) then
          table.insert(rval, '"' .. json_private.encodeString(i) .. '":' .. json.encode(j))
        end
      end
    end
    if bArray then
      return '[' .. table.concat(rval,',') ..']'
    else
      return '{' .. table.concat(rval,',') .. '}'
    end
  end
  
  -- Handle null values
  if vtype=='function' and v==json.null then
    return 'null'
  end
  
  assert(false,'encode attempt to encode unsupported type ' .. vtype .. ':' .. tostring(v))
end


--- Decodes a JSON string and returns the decoded value as a Lua data structure / value.
-- @param s The string to scan.
-- @param [startPos] Optional starting position where the JSON string is located. Defaults to 1.
-- @param Lua object, number The object that was scanned, as a Lua table / string / number / boolean or nil,
-- and the position of the first character after
-- the scanned JSON object.
function json.decode(s, startPos)
  startPos = startPos and startPos or 1
  startPos = decode_scanWhitespace(s,startPos)
  assert(startPos<=string.len(s), 'Unterminated JSON encoded object found at position in [' .. s .. ']')
  local curChar = string.sub(s,startPos,startPos)
  -- Object
  if curChar=='{' then
    return decode_scanObject(s,startPos)
  end
  -- Array
  if curChar=='[' then
    return decode_scanArray(s,startPos)
  end
  -- Number
  if string.find("+-0123456789.e", curChar, 1, true) then
    return decode_scanNumber(s,startPos)
  end
  -- String
  if curChar==[["]] or curChar==[[']] then
    return decode_scanString(s,startPos)
  end
  if string.sub(s,startPos,startPos+1)=='/*' then
    return json.decode(s, decode_scanComment(s,startPos))
  end
  -- Otherwise, it must be a constant
  return decode_scanConstant(s,startPos)
end

--- The null function allows one to specify a null value in an associative array (which is otherwise
-- discarded if you set the value with 'nil' in Lua. Simply set t = { first=json.null }
function json.null()
  return json.null -- so json.null() will also return null ;-)
end
-----------------------------------------------------------------------------
-- Internal, PRIVATE functions.
-- Following a Python-like convention, I have prefixed all these 'PRIVATE'
-- functions with an underscore.
-----------------------------------------------------------------------------

--- Scans an array from JSON into a Lua object
-- startPos begins at the start of the array.
-- Returns the array and the next starting position
-- @param s The string being scanned.
-- @param startPos The starting position for the scan.
-- @return table, int The scanned array as a table, and the position of the next character to scan.
function decode_scanArray(s,startPos)
  local array = {}	-- The return value
  local stringLen = string.len(s)
  assert(string.sub(s,startPos,startPos)=='[','decode_scanArray called but array does not start at position ' .. startPos .. ' in string:\n'..s )
  startPos = startPos + 1
  -- Infinite loop for array elements
  repeat
    startPos = decode_scanWhitespace(s,startPos)
    assert(startPos<=stringLen,'JSON String ended unexpectedly scanning array.')
    local curChar = string.sub(s,startPos,startPos)
    if (curChar==']') then
      return array, startPos+1
    end
    if (curChar==',') then
      startPos = decode_scanWhitespace(s,startPos+1)
    end
    assert(startPos<=stringLen, 'JSON String ended unexpectedly scanning array.')
    object, startPos = json.decode(s,startPos)
    table.insert(array,object)
  until false
end

--- Scans a comment and discards the comment.
-- Returns the position of the next character following the comment.
-- @param string s The JSON string to scan.
-- @param int startPos The starting position of the comment
function decode_scanComment(s, startPos)
  assert( string.sub(s,startPos,startPos+1)=='/*', "decode_scanComment called but comment does not start at position " .. startPos)
  local endPos = string.find(s,'*/',startPos+2)
  assert(endPos~=nil, "Unterminated comment in string at " .. startPos)
  return endPos+2  
end

--- Scans for given constants: true, false or null
-- Returns the appropriate Lua type, and the position of the next character to read.
-- @param s The string being scanned.
-- @param startPos The position in the string at which to start scanning.
-- @return object, int The object (true, false or nil) and the position at which the next character should be 
-- scanned.
function decode_scanConstant(s, startPos)
  local consts = { ["true"] = true, ["false"] = false, ["null"] = nil }
  local constNames = {"true","false","null"}

  for i,k in pairs(constNames) do
    if string.sub(s,startPos, startPos + string.len(k) -1 )==k then
      return consts[k], startPos + string.len(k)
    end
  end
  assert(nil, 'Failed to scan constant from string ' .. s .. ' at starting position ' .. startPos)
end

--- Scans a number from the JSON encoded string.
-- (in fact, also is able to scan numeric +- eqns, which is not
-- in the JSON spec.)
-- Returns the number, and the position of the next character
-- after the number.
-- @param s The string being scanned.
-- @param startPos The position at which to start scanning.
-- @return number, int The extracted number and the position of the next character to scan.
function decode_scanNumber(s,startPos)
  local endPos = startPos+1
  local stringLen = string.len(s)
  local acceptableChars = "+-0123456789.e"
  while (string.find(acceptableChars, string.sub(s,endPos,endPos), 1, true)
	and endPos<=stringLen
	) do
    endPos = endPos + 1
  end
  local stringValue = 'return ' .. string.sub(s,startPos, endPos-1)
  local stringEval = loadstring(stringValue)
  assert(stringEval, 'Failed to scan number [ ' .. stringValue .. '] in JSON string at position ' .. startPos .. ' : ' .. endPos)
  return stringEval(), endPos
end

--- Scans a JSON object into a Lua object.
-- startPos begins at the start of the object.
-- Returns the object and the next starting position.
-- @param s The string being scanned.
-- @param startPos The starting position of the scan.
-- @return table, int The scanned object as a table and the position of the next character to scan.
function decode_scanObject(s,startPos)
  local object = {}
  local stringLen = string.len(s)
  local key, value
  assert(string.sub(s,startPos,startPos)=='{','decode_scanObject called but object does not start at position ' .. startPos .. ' in string:\n' .. s)
  startPos = startPos + 1
  repeat
    startPos = decode_scanWhitespace(s,startPos)
    assert(startPos<=stringLen, 'JSON string ended unexpectedly while scanning object.')
    local curChar = string.sub(s,startPos,startPos)
    if (curChar=='}') then
      return object,startPos+1
    end
    if (curChar==',') then
      startPos = decode_scanWhitespace(s,startPos+1)
    end
    assert(startPos<=stringLen, 'JSON string ended unexpectedly scanning object.')
    -- Scan the key
    key, startPos = json.decode(s,startPos)
    assert(startPos<=stringLen, 'JSON string ended unexpectedly searching for value of key ' .. key)
    startPos = decode_scanWhitespace(s,startPos)
    assert(startPos<=stringLen, 'JSON string ended unexpectedly searching for value of key ' .. key)
    assert(string.sub(s,startPos,startPos)==':','JSON object key-value assignment mal-formed at ' .. startPos)
    startPos = decode_scanWhitespace(s,startPos+1)
    assert(startPos<=stringLen, 'JSON string ended unexpectedly searching for value of key ' .. key)
    value, startPos = json.decode(s,startPos)
    object[key]=value
  until false	-- infinite loop while key-value pairs are found
end

-- START SoniEx2
-- Initialize some things used by decode_scanString
-- You know, for efficiency
local escapeSequences = {
  ["\\t"] = "\t",
  ["\\f"] = "\f",
  ["\\r"] = "\r",
  ["\\n"] = "\n",
  ["\\b"] = "\b"
}
setmetatable(escapeSequences, {__index = function(t,k)
  -- skip "\" aka strip escape
  return string.sub(k,2)
end})
-- END SoniEx2

--- Scans a JSON string from the opening inverted comma or single quote to the
-- end of the string.
-- Returns the string extracted as a Lua string,
-- and the position of the next non-string character
-- (after the closing inverted comma or single quote).
-- @param s The string being scanned.
-- @param startPos The starting position of the scan.
-- @return string, int The extracted string as a Lua string, and the next character to parse.
function decode_scanString(s,startPos)
  assert(startPos, 'decode_scanString(..) called without start position')
  local startChar = string.sub(s,startPos,startPos)
  -- START SoniEx2
  -- PS: I don't think single quotes are valid JSON
  assert(startChar == [["]] or startChar == [[']],'decode_scanString called for a non-string')
  --assert(startPos, "String decoding failed: missing closing " .. startChar .. " for string at position " .. oldStart)
  local t = {}
  local i,j = startPos,startPos
  while string.find(s, startChar, j+1) ~= j+1 do
    local oldj = j
    i,j = string.find(s, "\\.", j+1)
    local x,y = string.find(s, startChar, oldj+1)
    if not i or x < i then
      i,j = x,y-1
    end
    table.insert(t, string.sub(s, oldj+1, i-1))
    if string.sub(s, i, j) == "\\u" then
      local a = string.sub(s,j+1,j+4)
      j = j + 4
      local n = tonumber(a, 16)
      assert(n, "String decoding failed: bad Unicode escape " .. a .. " at position " .. i .. " : " .. j)
      -- math.floor(x/2^y) == lazy right shift
      -- a % 2^b == bitwise_and(a, (2^b)-1)
      -- 64 = 2^6
      -- 4096 = 2^12 (or 2^6 * 2^6)
      local x
      if n < 0x80 then
        x = string.char(n % 0x80)
      elseif n < 0x800 then
        -- [110x xxxx] [10xx xxxx]
        x = string.char(0xC0 + (math.floor(n/64) % 0x20), 0x80 + (n % 0x40))
      else
        -- [1110 xxxx] [10xx xxxx] [10xx xxxx]
        x = string.char(0xE0 + (math.floor(n/4096) % 0x10), 0x80 + (math.floor(n/64) % 0x40), 0x80 + (n % 0x40))
      end
      table.insert(t, x)
    else
      table.insert(t, escapeSequences[string.sub(s, i, j)])
    end
  end
  table.insert(t,string.sub(j, j+1))
  assert(string.find(s, startChar, j+1), "String decoding failed: missing closing " .. startChar .. " at position " .. j .. "(for string at position " .. startPos .. ")")
  return table.concat(t,""), j+2
  -- END SoniEx2
end

--- Scans a JSON string skipping all whitespace from the current start position.
-- Returns the position of the first non-whitespace character, or nil if the whole end of string is reached.
-- @param s The string being scanned
-- @param startPos The starting position where we should begin removing whitespace.
-- @return int The first position where non-whitespace was encountered, or string.len(s)+1 if the end of string
-- was reached.
function decode_scanWhitespace(s,startPos)
  local whitespace=" \n\r\t"
  local stringLen = string.len(s)
  while ( string.find(whitespace, string.sub(s,startPos,startPos), 1, true)  and startPos <= stringLen) do
    startPos = startPos + 1
  end
  return startPos
end

--- Encodes a string to be JSON-compatible.
-- This just involves back-quoting inverted commas, back-quotes and newlines, I think ;-)
-- @param s The string to return as a JSON encoded (i.e. backquoted string)
-- @return The string appropriately escaped.

local escapeList = {
    ['"']  = '\\"',
    ['\\'] = '\\\\',
    ['/']  = '\\/', 
    ['\b'] = '\\b',
    ['\f'] = '\\f',
    ['\n'] = '\\n',
    ['\r'] = '\\r',
    ['\t'] = '\\t'
}

function json_private.encodeString(s)
 local s = tostring(s)
 return s:gsub(".", function(c) return escapeList[c] end) -- SoniEx2: 5.0 compat
end

-- Determines whether the given Lua type is an array or a table / dictionary.
-- We consider any table an array if it has indexes 1..n for its n items, and no
-- other data in the table.
-- I think this method is currently a little 'flaky', but can't think of a good way around it yet...
-- @param t The table to evaluate as an array
-- @return boolean, number True if the table can be represented as an array, false otherwise. If true,
-- the second returned value is the maximum
-- number of indexed elements in the array. 
function isArray(t)
  -- Next we count all the elements, ensuring that any non-indexed elements are not-encodable 
  -- (with the possible exception of 'n')
  if (t == json.EMPTY_ARRAY) then return true, 0 end
  if (t == json.EMPTY_OBJECT) then return false end
  
  local maxIndex = 0
  for k,v in pairs(t) do
    if (type(k)=='number' and math.floor(k)==k and 1<=k) then	-- k,v is an indexed pair
      if (not isEncodable(v)) then return false end	-- All array elements must be encodable
      maxIndex = math.max(maxIndex,k)
    else
      if (k=='n') then
        if v ~= (t.n or #t) then return false end  -- False if n does not hold the number of elements
      else -- Else of (k=='n')
        if isEncodable(v) then return false end
      end  -- End of (k~='n')
    end -- End of k,v not an indexed pair
  end  -- End of loop across all pairs
  return true, maxIndex
end

--- Determines whether the given Lua object / table / variable can be JSON encoded. The only
-- types that are JSON encodable are: string, boolean, number, nil, table and json.null.
-- In this implementation, all other types are ignored.
-- @param o The object to examine.
-- @return boolean True if the object should be JSON encoded, false if it should be ignored.
function isEncodable(o)
  local t = type(o)
  return (t=='string' or t=='boolean' or t=='number' or t=='nil' or t=='table') or
     (t=='function' and o==json.null) 
end

return json

misc.lua

-- https://github.com/profburke/colorswatches/tree/master/src/colorswatches
-- https://github.com/kikito/i18n.lua
-- https://github.com/Tieske/date








local object = {
    x = 0,
    y = 0,
    width = 0,
    height = 0,
    rotation = 0,
}

function isInSquare(x, y, object)
    local theta, c, s, cx, cy
    theta = math.rad(object.rotation or 0)
    c, s = math.cos(-theta), math.sin(-theta)
    cx = object.x + c*(x - object.x) - s*(y - object.y)
    cy = object.y + s*(x - object.x) + c*(y - object.y)

    if math.abs(cx-object.x)<object.length/2 and math.abs(cy-object.y)<object.height/2 then
        return true
    end

    return false
end

function eventClick(name, x, y)
    for i=#map.grounds,1,-1 do
        local ground = isInSquare(x, y, object)
    end
end

function definitely_not_intersecting(a, b)
    -- we put everything into a coordinate system where rectangle a is centered at the origin
    -- with no rotation.  i.e., it's corners are (-a.w/2,-a.h/2) and (a.w/2,a.h/2)
    --
    -- we'll need these a lot
    (a_w2, a_h2, b_w2, b_h2) = (a.w/2, a.h/2, b.w/2, b.h/2)
    --
    -- first we put the center of b into this system
    -- translate
    b_xc_tmp = (b.x+b_w2) - (a.x+a_w2)
    b_yc_tmp = (b.y+b_h2) - (a.y+a_h2)
    -- rotate by -a.theta
    c = math.cos(-a.theta)
    s = math.sin(-a.theta)
    b_xc = b_xc_tmp*c - b_yc_tmp*s
    b_yc = b_yc_tmp*c + b_xc_tmp*s
    --
    -- next we compute each corner of rectangle b relative to (b_xc,b_yc)
    theta = b.theta - a.theta
    c = math.cos(theta)
    s = math.sin(theta)
    -- because we're rotating around the center, we have some symmetry
    b_x1 = b_w2*c - b_h2*s
    b_y1 = b_w2*s + b_h2*c
    b_x2 = b_w2*c + b_h2*s
    b_y2 = b_w2*s - b_h2*c
    b_xs = [b_x1, b_x2, -b_x1, -b_x2]
    b_ys = [b_y1, b_y2, -b_y1, -b_y2]
    --
    -- find the bounding rectangle
    b_xmin = b_xc + min(b_xs)
    b_xmax = b_xc + max(b_xs)
    b_ymin = b_yc + min(b_ys)
    b_ymax = b_yc + max(b_ys)
    --
    -- check for intersection with rectangle a
    return b_xmax < -a_w2 or b_xmin > a_w2 or b_ymax < -a_h2 or b_ymin > a_h2
end

float a = d.Dot( d ) ;
float b = 2*f.Dot( d ) ;
float c = f.Dot( f ) - r*r ;

a = {x=0, y=200}
b = {x=800, y=200}
circle = {x=400, y=200, r=100}

function line_intersects_circle(pointA,pointB,circle)
    local discriminant = b * b - 4 * a * c
    if discriminant < 0 then
        -- no intersection
    else
        -- ray didn't totally miss sphere,
        -- so there is a solution to
        -- the equation.

        discriminant = math.sqrt(discriminant)

        -- either solution may be on or off the ray so need to test both
        -- t1 is always the smaller value, because BOTH discriminant and
        -- a are nonnegative.
        float t1 = (-b - discriminant)/(2*a)
        float t2 = (-b + discriminant)/(2*a)

        -- 3x HIT cases:
        --          -o->             --|-->  |            |  --|->
        -- Impale(t1 hit,t2 hit), Poke(t1 hit,t2>1), ExitWound(t1<0, t2 hit), 

        -- 3x MISS cases:
        --       ->  o                     o ->              | -> |
        -- FallShort (t1>1,t2>1), Past (t1<0,t2<0), CompletelyInside(t1<0, t2>1)

        if t1 >= 0 and t1 <= 1 then
            -- t1 is the intersection, and it's closer than t2
            -- (since t1 uses -b - discriminant)
            -- Impale, Poke
            return true
        end

        -- here t1 didn't intersect so we are either started
        -- inside the sphere or completely past it
        if t2 >= 0 and t2 <= 1 then
            -- ExitWound
            return true
        end

        -- no intn: FallShort, Past, CompletelyInside
        return false
    end
end




















function dump(value, valueName, tabs)
    tabs=tabs or ""
    local str = ''
    local t=type(value)
    if valueName then
        str = str .. (tabs .. t .. " " .. tostring(valueName) .. " = " .. tostring(value) .. "\n")
    else
        str = str .. (tabs .. t .. " " .. tostring(value) .. "\n")
    end
    if t=="table" then
        for n,v in pairs(value) do
            if v==value then
                str = str .. tabs.."\tself "..n
            else
                str = str .. dump(v,n,tabs.."\t")
            end
        end
    end
    return str
end








function lua_to_string(value)
    if type(value) == 'table' then
        -- to table
    elseif type(value) == 'number' then
        return tostring(value)
    elseif type(value) == 'string' then
        return '"' .. value .. '"'
    elseif type(value) == 'boolean' then
        return value and 'true' or 'false'
    end
end

function string_to_lua(value)
    if value == 'true' then
        return true
    elseif value == 'false' then
        return false
    elseif value == 'nil' then
        return nil
    elseif tonumber(value) then
        return tonumber(value)
    else
        return value
    end
end





function tables_equal(tbl1, tbl2)
    local tbl1count, tbl2count = 0, 0
    for key, value in pairs(tbl1) do
        tbl1count = tbl1count + 1
        if tbl2[key] and value == tbl2[key] then
            if type(value) == 'table' then
                if not tables_equal(value, tbl2[key]) then
                    return false
                end
            end
        else
            return false
        end
    end
    for key, value in pairs(tbl2) do
        tbl2count = tbl2count + 1
    end
    if tbl1count ~= tbl2count then
        return false
    end
    return true
end


--=====================================================
-- the reason this routine is needed is because lua does not 
-- have a sort indexed table function
function table_sort(a, sortfield)
local new1 = {}
local new2 = {}
    for k,v in pairs(a) do
        table.insert(new1, { key=k, val=v } )       
    end
    table.sort(new1, function (a,b) return (a.val[sortfield] < b.val[sortfield]) end)  
    for k,v in pairs(new1) do
        table.insert(new2, v.val)
    end
    return new2
end

---============================================================
function padzero(s, count)
    return string.rep("0", count-string.len(s)) .. s 
end

--========================================================================
-- get date parts for a given ISO 8601 date format (http://richard.warburton.it )
function get_date_parts(date_str)
  _,_,y,m,d=string.find(date_str, "(%d+)-(%d+)-(%d+)")
  return tonumber(y),tonumber(m),tonumber(d)
end

--====================================================
function getmonth(month)
    local months = { "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" }
    return months[tonumber(month)]
end

--====================================================
function getday_posfix(day)
local idd = math.mod(day,10)
       return   (idd==1 and day~=11 and "st")  or (idd==2 and day~=12 and "nd") or (idd==3 and day~=13 and "rd") or "th"
end


--========================================================================
--  Given a date of certain date_format, returns the date parts yy,mm,dd
--  eg. "12 May 2007" with date_format "dd mmm yyyy"
--   or   "12.05.07" with date_format "dd.mm.yy"
--  will return 2007, 5, 12
--
function get_formatted_date_parts(date_str, date_format)
    local d,m,y, arr, x, yy, mm, dd, use_month_names
    local months = { jan=1, feb=2, mar=3, apr=4, may=5, jun=6, jul=7, aug=8, sep=9, oct=10, nov=11, dec=12 }

    if (date_format) then
    
        if string.find(date_format, "mmm") then
            use_month_names = true
        else
            use_month_names = false
        end

        d = string.find(date_format, "dd")
        m = string.find(date_format, "mm")
        y = string.find(date_format, "yy")
        
        arr = { { pos=y, b="yy" }, { pos=m, b="mm" } , { pos=d, b="dd" }  }
        arr = table_sort(arr, "pos")

        date_format = string.gsub(date_format,"yyyy","(%%d+)")
        date_format = string.gsub(date_format,"mmm","(%%a+)")
        date_format = string.gsub(date_format,"yy","(%%d+)")
        date_format = string.gsub(date_format,"mm","(%%d+)")
        date_format = string.gsub(date_format,"dd","(%%d+)")
        date_format = string.gsub(date_format," ","%%s")
    else
        date_format = "(%d+)-(%d+)-(%d+)"
        arr = { { pos=1, b="yy" }, { pos=2, b="mm" } , { pos=3, b="dd" }  }
    end

    if (date_str and date_str~="") then     
        _, _, arr[1].c, arr[2].c, arr[3].c = string.find(string.lower(date_str), date_format)
    else
        return nil, nil, nil
    end


    arr = table_sort(arr, "b")
    yy = arr[3].c
    mm = arr[2].c
    dd = arr[1].c

    if (use_month_names) then       
    
        mm = months[lower(string.sub(mm,1,3))]
        if (not mm) then
            error("Invalid month name.")
        end
    end

    -- for naughty people who still use two digit years.

    if (string.len(yy)==2) then
        if (tonumber(yy)>40) then
            yy = "19"..yy
        else
            yy = "20"..yy
        end
    end

    return tonumber(yy),tonumber(mm),tonumber(dd)
end



--========================================================================
-- Note : date_str has to be  ISO 8601 date format  ie. yyyy-mm-dd
--
function format_date(date_str, dateformat)
local iyy, imm, idd 

    if (date_str and date_str~="") then
        iyy, imm, idd =  get_date_parts(date_str)
        dateformat = string.gsub(dateformat, "DDD",  idd..string.upper(getday_posfix(idd)))
        dateformat = string.gsub(dateformat, "ddd",  idd..getday_posfix(idd) )
        dateformat = string.gsub(dateformat, "dd", padzero(idd,2))
        dateformat = string.gsub(dateformat, "MMM", string.upper(getmonth(imm)))
        dateformat = string.gsub(dateformat, "mmm", getmonth(imm))
        dateformat = string.gsub(dateformat, "mm", padzero(imm,2))
        dateformat = string.gsub(dateformat, "yyyy", padzero(iyy,4))
        dateformat = string.gsub(dateformat, "yy", string.sub(padzero(iyy,4),3,4))
    else
        dateformat = ""
    end

    return(dateformat)
end

--===============================================
-- convert date to excel serial day number
--
function date_to_excel_date(dd, mm, yy) 
local days, monthdays, leapyears, nonleapyears, nonnonleapyears

    monthdays= { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }

    leapyears=tonumber(math.floor((yy-1900)/4));
    nonleapyears=tonumber(math.floor((yy-1900)/100))
    nonnonleapyears=tonumber(math.floor((yy-1600)/400))

    if ((math.mod(yy,4)==0) and mm<3) then
      leapyears = leapyears - 1
    end

    days= 365 * (yy-1900) + leapyears - nonleapyears + nonnonleapyears

    c=1
    while (c<mm) do
      days = days + monthdays[c]
    c=c+1
    end

    days=days+dd+1

    return days
end













-- adate = os.date()
-- print("Todays date according to your OS format :", adate)

-- -- for example "mm/dd/yyyy" could be your OS locale date format.
-- yy,mm,dd =  get_formatted_date_parts(adate, "mm/dd/yyyy")

-- ISO_date = yy .. "-" .. mm .. "-" .. dd

-- print("Date formated in ISO 8601", ISO_date)

-- print(format_date(ISO_date, "dd MMM yyyy") )
-- print(format_date(ISO_date, "ddd mmm yyyy") )
-- print(format_date(ISO_date, "dd/mm/yy") )
-- print(format_date(ISO_date, "yyyy.mm.dd") )
-- print(format_date(ISO_date, "Today is the ddd of mmm, yyyy.") )

-- print( date_to_excel_date(22, 2, 2009)  )   -- outputs 39866


print( tables_equal({'a', {'a'}}, {'a', {'a'}}) )



























local argparse = require "argparse"
local inspect = require "inspect"
local json = require "json"

function dump(value)
    print(inspect(value))
end

function get_tip(context, wrong_name)
   local context_pool = {}
   local possible_name
   local possible_names = {}

   for name in pairs(context) do
      if type(name) == "string" then
         for i = 1, #name do
            possible_name = name:sub(1, i - 1) .. name:sub(i + 1)

            if not context_pool[possible_name] then
               context_pool[possible_name] = {}
            end

            table.insert(context_pool[possible_name], name)
         end
      end
   end

   for i = 1, #wrong_name + 1 do
      possible_name = wrong_name:sub(1, i - 1) .. wrong_name:sub(i + 1)

      if context[possible_name] then
         possible_names[possible_name] = true
      elseif context_pool[possible_name] then
         for _, name in ipairs(context_pool[possible_name]) do
            possible_names[name] = true
         end
      end
   end

   local first = next(possible_names)

   if first then
      if next(possible_names, first) then
         local possible_names_arr = {}

         for name in pairs(possible_names) do
            table.insert(possible_names_arr, "'" .. name .. "'")
         end

         table.sort(possible_names_arr)
         return "\nDid you mean one of these: " .. table.concat(possible_names_arr, " ") .. "?"
      else
         return "\nDid you mean '" .. first .. "'?"
      end
   else
      return ""
   end
end


dump(str)






























--[[
    !img
    !img -h
    !img --help
    !img remove
    !img [name]
    !omo hello world
    !omo hello world --size=24

    if [name] == '*' then
        foreach
            --all
        end
    else
        --single
    end
]]

function names(name, fnc, ...)
    if name == '*' then
        for key, value in pairs(users) do
            fnc(...)
        end
    else
        fnc(...)
    end
end

config = {
    name = 'utility',
    owner = 'Username',
    locale = 'en',
    debug = true,
    official = false
}

user = {
    keybinds = {
        dash = {'CTRL' = true, 'LEFT' = true},
        up = {'UP'}
    },
    stats = {
        ph = {
            rounds = 0,
            wins = 0,
            losses = 0
        }
    }
}

commands ={
    -- command definition
    cmd = {
        hidden = true, -- hidden from 
        permissions = {}, -- list of user groups who can use the command

        helpMessage = "thing.help",
        options = {
            ['--help'] = 
            ['-h'] = 
        }
        execute = function(userWhoExecuted, originalCommand, )

        end
    }
}

if not config.official then
    tfm.exec.addImage = function()
        print('Sorry, you cannot use this function.')
        return 1
    end
    tfm.exec.chatMessage = function(str, name)
        print(str .. ' (for ' .. name .. ')')
    end
    loop = eventLoop
end