Lua Nested Unpack Bug?

Question

Question:

I'm trying to unpack an array into an array, but it only works if it's the last item unpacked, if there is anything after it only the first element is unpacked. The following is a very basic example of what I'm trying to do. Is there a better way to do this, or is this a bug I'll have to cope with? I don't want to use table.insert as this seems to be much more readable adding within the definition of the table with something like unpack.

Code:

   print ("Error 1")
   local table1 = { {1,1}, {2,2}, {3,3} }
   local table2 = { {0,0}, unpack (table1), {4,4} }
   for n,item in ipairs (table2) do print (unpack(item)) end

   print ("Good")
   table1 = { {1,1}, {2,2}, {3,3} }
   table2 = { {0,0}, unpack (table1) }
   for n,item in ipairs (table2) do print (unpack(item)) end

   print ("Error 2")
   table1 = { {1,1}, {2,2}, {3,3} }
   table2 = { {0,0}, unpack (table1), unpack (table1) }
   for n,item in ipairs (table2) do print (unpack(item)) end

Output:

Error 1
0       0
1       1 -- {2,2} & {3,3} cut off.
4       4
Good
0       0
1       1 -- All elements unpacked.
2       2
3       3
Error 2
0       0
1       1 -- {2,2} & {3,3} cut off.
1       1 -- All elements unpacked.
2       2
3       3

Note:

I'm running version 5.1.

Answer 1

This is not a bug. A function call that returns multiple values is adjusted to the first value if the call is not the last one. The manual says that at http://www.lua.org/manual/5.1/manual.html#2.5