为什么这个代码不使用函数子类型使用Flow进行类型检查？

Why isn't this code typechking with flow?

为什么这个代码没有流量类型?

function runFunction<I, O>( fun: (...args:Array<I>) => O, args:Array<I> ): O {
    var res = fun.apply(null, args);
    return res;
}

function myFun(first: number, second: number): string {
    return first + ", " + second;
}

runFunction(myFun, [1, 2]);

I think I am doing everything right, and I still get this

我想我做的一切都是正确的,我仍然得到这个

function type
Too few arguments (expected default/rest parameters in function)
function

rest array of type parameter I of function call
This type is incompatible with
number

1 个解决方案

#1

Oh now I get it. I would have to do this

哦,现在我明白了。我必须这样做

function runFunction<I, O>( fun: (...args:Array<I>) => O, args:Array<I> ): O {
    var res = fun.apply(null, args);
    return res;
}

function myFun(...args:Array<number>): string {
    return args[0] + ", " + args[1];
}

runFunction(myFun, [1, 2]);

So, if I get it correctly, "function that takes 2 numbers" is not a subtype of "function that takes any amount of any parameters", even when it logically is a subtype.

因此,如果我正确地得到它,“带2个数字的函数”不是“接受任何数量的任何参数的函数”的子类型,即使它在逻辑上是一个子类型。

I am not sure what would be the right solution... I understand, kind of, the logic, but it's confusing slightly.

我不确定什么是正确的解决方案...我理解,有点,逻辑,但它有点令人困惑。

#1