variable 'xxx' unsafe in 'case'的处理

问题描述：

case get(?Player_LoopTaskInfo) of
    {TargetCnt, TaskStar, TaskExp} ->
        ok;
    _ ->
        throw("not_found_loop_task_info")    
end

在case语句中，这样写，编译时，会提示变量unsafe，解决编译器报错的方法有下面两个：

1、给unsafe的变量赋值

case get(?Player_LoopTaskInfo) of
    {TargetCnt, TaskStar, TaskExp} ->
        ok;
    _ ->
    TargetCnt=0,TaskStar=0,TaskExp=0,
        throw("not_found_loop_task_info")    
end

2、把case语句拆成函数

{TargetCnt, TaskStar, TaskExp} = valid_task_info(get(?Player_LoopTaskInfo))
valid_task_info({_, _, _} = Info) -> Info;
valid_task_info(_) -> throw("not_found_loop_task_info").