一个erer actor小演示

Question

[我是Erlang的新秀，累了为Spider编写代码：

-module(http).
-compile([export_all]).

init() ->
  ssl:start(),
  inets:start(),
  register(m, spawn(fun() -> loop() end)),
  register(fetch, spawn(fun() -> x() end)),
  ok.

start() ->
  L1 = [114689,114688,114691,114690], % detail page id

  lists:map(fun(Gid) ->
    io:format("~p ~n", [Gid]),
    fetch ! {go, Gid}
  end, L1),
  m ! done,
  done.

main(_) ->
  init(),
  start().

loop() ->
  io:fwrite("this is in loop!!"),
  receive
    {no_res, Gid} ->
      io:format("~p no res ! ~n", [Gid]),
      loop();
    {have_res, Gid} ->
      io:format("~p have res ! ~n", [Gid]),
      loop();
    done ->
      io:format("wowowow", [])
  end.

x() ->
  receive
    {go, Gid} ->
      http_post(Gid);
    _ ->
      ready
  end.

http_post(Gid) ->
  URL = "https://example.com", % url demo 
  Type = "application/json",
  ReqArr = ["[{\"id\": \"", integer_to_list(Gid), "\"}]"],
  ReqBody = string:join(ReqArr, ""),

  case httpc:request(post, {URL, [], Type, ReqBody}, [], []) of
    {ok, {_, _, ResBody}} ->
      if
        length(ResBody) =:= 0 ->
          io:format("Y: ~p ~n", [Gid]);
          m ! {no_res, Gid};
        true ->
          io:format("N: ~p ~n", [Gid])
          m ! {have_res, Gid}
      end;
    {error, Reason} ->
      io:format("error cause ~p~n", [Reason]);
    _ ->
      io:format("error cause ~n", [])
  end.

现在，当我执行代码时，过程将立即终止，登录：

我有两个问题：

1. 我如何解决这个问题？
2. 如果我在L1中有成千上万个ID，如何解决？产生几十个演员？如果是，您如何确定哪个演员要receive哪个ID？

Answer 1

1）而不是在loop()周围包裹一个匿名函数：

register(m, spawn(fun() -> loop() end)),

您可以拨打spawn/3：

register(m, spawn(?MODULE, loop, []) ),

这里相同：

register(fetch, spawn(fun() -> x() end)),