save lua table contents to file (useful for logging purposes)

table2file.lua

function save_configs(filename, opt)
-- prints the contents of a table into a file

    local function table_print (tt, indent, done)
                    done = done or {}
                    indent = indent or 0
                    if type(tt) == "table" then
                      local sb = {}
                      for key, value in pairs (tt) do
                        table.insert(sb, string.rep (" ", indent)) -- indent it
                        if type (value) == "table" and not done [value] then
                          done [value] = true
                          table.insert(sb, tostring(key) .. ': ');
                          table.insert(sb, "{\n");
                          table.insert(sb, table_print (value, indent + 2, done))
                          table.insert(sb, string.rep (" ", indent)) -- indent it
                          table.insert(sb, "}\n");
                        elseif "number" == type(key) then
                          table.insert(sb, string.format("\"%s\"\n", tostring(value)))
                        else
                          table.insert(sb, string.format(
                              "%s = \"%s\"\n", tostring (key), tostring(value)))
                         end
                      end
                      return table.concat(sb)
                    else
                      return tt .. "\n"
                    end
    end -- local function

  -- open file
    local file = io.open(filename,"w")
    
    file:write('---------------------------------------------------------------------------------------\n')
    file:write('\n')
    file:write('Table info.\n')
    file:write('\n')
    file:write('---------------------------------------------------------------------------------------\n\n\n\n')
    
    file:write(table_print(opt,1))
    
    -- close file
    file:close()
end