Print_r in Lua

sof-36834786.lua

-- Possible solution to http://stackoverflow.com/questions/36834786/how-to-save-a-table-to-a-file-from-lua/36836187#36836187

function print_r (t, fd)
    fd = fd or io.stdout
    local function print(str)
       str = str or ""
       fd:write(str.."\n")
    end
    local print_r_cache={}
    local function sub_print_r(t,indent)
        if (print_r_cache[tostring(t)]) then
            print(indent.."*"..tostring(t))
        else
            print_r_cache[tostring(t)]=true
            if (type(t)=="table") then
                for pos,val in pairs(t) do
                    if (type(val)=="table") then
                        print(indent.."["..pos.."] => "..tostring(t).." {")
                        sub_print_r(val,indent..string.rep(" ",string.len(pos)+8))
                        print(indent..string.rep(" ",string.len(pos)+6).."}")
                    elseif (type(val)=="string") then
                        print(indent.."["..pos..'] => "'..val..'"')
                    else
                        print(indent.."["..pos.."] => "..tostring(val))
                    end
                end
            else
                print(indent..tostring(t))
            end
        end
    end
    if (type(t)=="table") then
        print(tostring(t).." {")
        sub_print_r(t,"  ")
        print("}")
    else
        sub_print_r(t,"  ")
    end
    print()
end

function savetxt(t, filename)
   local fd = io.open(filename, "wt")
   print_r(t, fd)
   fd:close()
end

local t = {
   test = "test",
}
savetxt(t, "test.txt")