Ada对象"Train"在声明结束前不能使用

Question

这段代码有什么问题？编译器说两件事,没有Run条目和Run接受与条目不匹配(两者似乎都是错误的),并且单独表示Train在声明之前不能使用(但它已经被声明).请向我解释发生了什么.

我对显示整个代码犹豫不决,但可以这样做.

type ItineraryType is array (0..255) of Integer;
type Train is record
    Label : Integer;
    Capacity : Integer;
    Maxspeed : Integer;
    Starts : Integer;
    Itinerary : ItineraryType;
    Stops : Integer;
    lock : access Mutex;
end record;

task type TrainThread is
    entry Run (train1:Train);
end;
task body TrainThread is
    train : Train;
begin
    accept Run (train1:Train) do
        train := train1;
    end;
end;

-- part of main
train1 := new TrainThread;
train1.Run(trains(i));

---

main.adb:51:05: warning: no accept for entry "Run"
main.adb:52:17: object "Train" cannot be used before end of its declaration
main.adb:54:09: no entry declaration matches accept statement
gnatmake: "main.adb" compilation error

Answer 1

Ada不区分大小写,所以train并且Train是等价的.因此声明train : Train将始终无效.(不可否认,在这种情况下,gnat的信息会更好)