Re: Lua Pickle error?

On Sat, Jan 23, 2010 at 8:33 PM, Joe Andresen <joe.andresen@gmail.com> wrote:

Sorry for the email spam, but i thought the output of the pickle function might help ( and the error)... It's actually unpickle that is breaking with the error.

the dofile in unpickle complains about a symbol at eof.

i understand that the end of the file is malformed, but why would loadstring and gentables() work and not dofile?

here is the file.
thing.lua

return {

["contact"]={2},
[{3}]=10,
["name"]="foo",
[10]=11,
["a b"]="zzz",
["t"]={3},
["ssn"]=123456789,

[{1}]=5,
},
{
["phone"]="555-1\r\
212",
["loop"]={1},
["email"]="foo@foo.com",

},
{
[1]=1,
},

On Sat, Jan 23, 2010 at 8:30 PM, Joe Andresen <joe.andresen@gmail.com> wrote:

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.)