Re: Lua Pickle error?

[Joe Andresen <joe.andresen@...>]

I seem to be having a problem with the changes I made to Pickle to write to a file.

the fundamental difference is i use dofile instead of gentables = loadstring(s) and t = gentables().

can someone explain the difference and why dofile might not work?

Here is my code below :

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

-- Pickle.lua

-- A table serialization utility for lua

-- Steve Dekorte, http://www.dekorte.com, Apr 2000

-- Edited by: Joe Andresen, Jan 2010

-- Freeware

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

function pickle(t, filename)

  return Pickle:clone():pickle_(t,filename)

end

Pickle = {

  clone = function (t) local nt={}; for i, v in pairs(t) do nt[i]=v end return nt end 

}

function Pickle:pickle_(root, filename)

  if string.find(filename, ".lua") then 

    io.output(filename, "w" )

  else

    filename = filename .. ".lua"

    io.output(filename..".lua")

  end   

  if type(root) ~= "table" then 

    error("can only pickle tables, not ".. type(root).."s")

    return false

  end

  self._tableToRef = {}

  self._refToTable = {}

  local savecount = 0

  self:ref_(root)

  local s = ""

  while table.getn(self._refToTable) > savecount do

    savecount = savecount + 1

    local t = self._refToTable[savecount]

    s = s.."{\n"

    for i, v in pairs(t) do

        s = string.format("%s[%s]=%s,\n", s, self:value_(i), self:value_(v))

    end

    s = s.."},\n"

  end

  string.format("{%s}", s)

  io.write("return ",s)

  io.close()

  return true

end

function Pickle:value_(v)

  local vtype = type(v)

  if     vtype == "string" then return string.format("%q", v)

  elseif vtype == "number" then return v

  elseif vtype == "table" then return "{"..self:ref_(v).."}"

  else --error("pickle a "..type(v).." is not supported")

  end  

end

function Pickle:ref_(t)

  local ref = self._tableToRef[t]

  if not ref then 

    if t == self then error("can't pickle the pickle class") end

    table.insert(self._refToTable, t)

    ref = table.getn(self._refToTable)

    self._tableToRef[t] = ref

  end

  return ref

end

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

-- unpickle

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

function unpickle(filename)

  --if type(s) ~= "string" then

  --  error("can't unpickle a "..type(s)..", only strings")

  --end

  local tables = dofile(filename)

  --local tables = gentables()

  

  for tnum = 1, table.getn(tables) do

    local t = tables[tnum]

    local tcopy = {}; for i, v in pairs(t) do tcopy[i] = v end

    for i, v in pairs(tcopy) do

      local ni, nv

      if type(i) == "table" then ni = tables[i[1]] else ni = i end

      if type(v) == "table" then nv = tables[v[1]] else nv = v end

      t[ni] = nv

    end

  end

  return tables[1]

end

function test()

  local t = {

    name = "foo", 

    ssn=123456789, 

    contact = { phone = "555-1\r\n212", email = "foo@foo.com"},

  }

  t.t = { 1 }

  t.contact.loop = t

  t["a b"] = "zzz"

  t[10] = 11

  t[t] = 5

  t[t.t] = 10

  local s = pickle(t, "thing.lua") 

  local ut = unpickle("thing.lua") 

  

print("pickled string:\n\n"..pickle( ut ))

  print("loop test:   "); eq(ut == ut.contact.loop)

  print("subitem test:"); eq(ut.contact.phone == t.contact.phone)

  print("number value:"); eq(ut.ssn == t.ssn)

  print("number index:"); eq(ut[10] == 11)

  print("table index: "); eq(ut[ut] == 5)

end

function eq(b)

  if b then print(" succeeded") else print(" failed") end

end  

end

test()

On Sat, Jan 23, 2010 at 11:23 AM, Andre Leiradella <aleirade@sct.microlink.com.br> wrote:

Oops, I should've taken a closer look at the code. Sorry.

Check Joe Andresen's post in this topic, it has an easier solution.

On 23/01/2010 13:52, Florian Weimer wrote:

* Andre Leiradella:

 

       clone = function (t) local nt={}; system_lib.for_each(t, function(i, v) nt[i] = v end) return nt end
   

 

       if system_lib.type_of(root) ~= system_lib.TABLE then
   

What is system_lib?  (Just in case Joe hasn't got it, either.)