Error when quitting LFE shell

[oubiwann]

When quitting the LFE shell on Erjang, I get the following:

> ^Dexception exit: #(error #(1 lfe_parse #(missing token)))
  in (lfe_io scan_and_parse 3)

> {error_logger,{{2014,4,6},{17,36,51}},supervisor_report,[{supervisor,{<0.0.683>,user_sup}},{errorContext,child_terminated},{reason,{badarg,[{queue,is_empty,[[]],[{file,"queue.erl"},{line,-1}]},{user,get_chars,7,[{file,"user.erl"},{line,600}]},{user,do_io_request,5,[{file,"user.erl"},{line,182}]},{user,server_loop,2,[{file,"user.erl"},{line,132}]}]}},{offender,[{pid,<0.0.688>},{mod,user_sup}]}]}
{error_logger,{{2014,4,6},{17,36,51}},"** Generic server ~p terminating \n** Last message in was ~p~n** When Server state == ~p~n** Reason for termination == ~n** ~p~n",[<0.0.683>,{'EXIT',<0.0.688>,{badarg,[{queue,is_empty,[[]],[{file,"queue.erl"},{line,-1}]},{user,get_chars,7,[{file,"user.erl"},{line,600}]},{user,do_io_request,5,[{file,"user.erl"},{line,182}]},{user,server_loop,2,[{file,"user.erl"},{line,132}]}]}},{state,user_sup,undefined,<0.0.688>,{<0.0.683>,user_sup}},{badarg,[{queue,is_empty,[[]],[{file,"queue.erl"},{line,-1}]},{user,get_chars,7,[{file,"user.erl"},{line,600}]},{user,do_io_request,5,[{file,"user.erl"},{line,182}]},{user,server_loop,2,[{file,"user.erl"},{line,132}]}]}]}
{error_logger,{{2014,4,6},{17,36,51}},crash_report,[[{initial_call,{supervisor_bridge,user_sup,['Argument__1']}},{pid,<0.0.683>},{registered_name,[]},{error_info,{exit,{badarg,[{queue,is_empty,[[]],[{file,"queue.erl"},{line,-1}]},{user,get_chars,7,[{file,"user.erl"},{line,600}]},{user,do_io_request,5,[{file,"user.erl"},{line,182}]},{user,server_loop,2,[{file,"user.erl"},{line,132}]}]},[{gen_server,terminate,6,[{file,"gen_server.erl"},{line,747}]},{proc_lib,init_p_do_apply,3,[{file,"proc_lib.erl"},{line,239}]}]}},{ancestors,[kernel_sup,<0.0.38>]},{messages,[]},{links,[<0.0.42>]},{dictionary,[]},{trap_exit,true},{status,running},{heap_size,65678000},{stack_size,0},{reductions,8}],[]]}
{error_logger,{{2014,4,6},{17,36,51}},supervisor_report,[{supervisor,{local,kernel_sup}},{errorContext,child_terminated},{reason,{badarg,[{queue,is_empty,[[]],[{file,"queue.erl"},{line,-1}]},{user,get_chars,7,[{file,"user.erl"},{line,600}]},{user,do_io_request,5,[{file,"user.erl"},{line,182}]},{user,server_loop,2,[{file,"user.erl"},{line,132}]}]}},{offender,[{pid,<0.0.683>},{name,user},{mfargs,{user_sup,start,[]}},{restart_type,temporary},{shutdown,2000},{child_type,supervisor}]}]}
{error_logger,{{2014,4,6},{17,36,51}},std_info,"Process <0.0.743> exited abnormally without links/monitors\nexit reason was: {terminated,[{io,put_chars,[<0.0.688>,unicode,[\"exception error: \",\"function_clause\",\"\\n\",[[\"  in \",[\"(\",[\":\",\" \",\"lists\",\" \",\"sublist\",\" \",[\"#(\",[\"error\",\" \",\"terminated\"],\")\"],\" \",\"1\"],\")\"],\"\\n\"],[32,32,105,110,32,40,\"lfe_scan\",32,\"string\",32,\"4\",41,10],[32,32,105,110,32,40,\"lfe_io\",32,\"scan_and_parse\",32,\"3\",41,10]]]]},{lfe_shell,server_loop,1,[{file,\"lfe_shell.erl\"},{line,106}]}]}\njava trace: erjang.ErlangRaise: {terminated,[{io,put_chars,[<0.0.688>,unicode,[\"exception error: \",\"function_clause\",\"\\n\",[[\"  in \",[\"(\",[\":\",\" \",\"lists\",\" \",\"sublist\",\" \",[\"#(\",[\"error\",\" \",\"terminated\"],\")\"],\" \",\"1\"],\")\"],\"\\n\"],[32,32,105,110,32,40,\"lfe_scan\",32,\"string\",32,\"4\",41,10],[32,32,105,110,32,40,\"lfe_io\",32,\"scan_and_parse\",32,\"3\",41,10]]]]},{lfe_shell,server_loop,1,[{file,\"lfe_shell.erl\"},{line,106}]}]}\n\tat erjang.m.erlang.ErlBif.raise(ErlBif.java)\n\tat erjang.m.io.io.o_request__3(io.erl:66)\n\tat erjang.m.io.io$FN_o_request__3.go(Unknown Source)\n\tat erjang.EFun1.invoke(Unknown Source)\n\tat erjang.m.lfe_shell.lfe_shell.server_loop__1(lfe_shell.erl:106)\n\tat erjang.m.lfe_shell.lfe_shell$FN_server_loop__1.go(Unknown Source)\n\tat erjang.m.erlang.ErlBif.apply(ErlBif.java:140)\n\tat erjang.m.erlang.ErlBif$FN_apply__2.go(Unknown Source)\n\tat erjang.EProc.execute1(EProc.java:682)\n\tat erjang.EProc.execute0(EProc.java:607)\n\tat erjang.EProc.execute(EProc.java:590)\n\tat kilim.Task._runExecute(Task.java)\n\tat kilim.WorkerThread.run(WorkerThread.java:32)\n"}

As opposed to what happens when quitting the Erlang shell:

11> *** Terminating erlang (nonode@nohost)
$

This may be an issue with LFE; I will discuss with Robert.

[eriksoe]

This one is fairly interesting; the queue which is part of the "user" process's state somehow gets to be []. I'd say this is not likely to be an LFE problem.

[krestenkrab]

Yes, very strange. How can user's input queue suddenly not be {<list>, <list>} i.e. a proper queue, but just <list>? This shouldn't happen. We'll have to trace down the bug to which call from user causes this strange value to appear.

[oubiwann]

Let me know if there's anything I can do to provide you with more details on this failure!

On Mon, Apr 7, 2014 at 10:52 AM, Kresten Krab Thorup < notifications@github.com> wrote:

Yes, very strange. How can user's input queue suddenly not be {,

} but just ? This shouldn't happen. We'll have to trace down the bug to which call from user causes this strange value to appear. ## Reply to this email directly or view it on GitHubhttps://github.com/trifork/erjang/issues/85#issuecomment-39761434 .