Vala是否支持自调用? [英] Does Vala support self-invoking?

问题描述

Vala是否支持自调用?是使用类还是方法?

Is there any way that Vala supports Self Invoking? Either with a class, or with a method?

JavaScript支持如下所示的自调用.我在找什么.

Javascript supports self invoking like below. Which is what im looking for.

   (function(){
   // some code…
   })();

我正在尝试将一个类加载到哈希图中以进行动态加载.

I'm attempting to load a class into a hashmap for dynamically loading.

推荐答案

using Gee;

[CCode (has_target = false)]
delegate void MyDelegate();

int main() {
        var map = new HashMap<string, MyDelegate>();

        map["one"] = () => { stdout.printf("1\n"); };
        map["two"] = () => { stdout.printf("2\n"); };

        MyDelegate d = map["two"];
        d();
        return 0;
}

如果在委托中需要目标，则必须编写包装器，请参见以下问题: 包含方法作为值的Gee HashMap

If you need a target in your delegate you have to write a wrapper, see this question: Gee HashMap containing methods as values

如您所见，您不需要自我发票.自我报价看起来像这样:

As you can see, you don't need self invokation. Self invokation would look something like this:

int main() {
        (() => { stdout.printf("Hello world!\n"); })();
        return 0;
}

Vala不支持此功能(我使用valac-0.22对其进行了测试).

This is not supported by Vala (I tested this with valac-0.22).

调用委托var可以按预期工作:

Invoking a delegate var works as expected:

delegate void MyDelegate();

int main() {
        MyDelegate d = () => { stdout.printf("Hello world!\n"); };
        d();
        return 0;
}

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