作为接收参数属性的泛型类型

所以你希望这个参数至少有这个属性 bar ,对吧? 这意味着它是

interface WithBar<T> {
    bar: T
}

const foo = <T>(someObject: WithBar<T>): T => {
    return someObject.bar
}

为了避免引入这种人为的 WithBar 类型,直接写入

const foo = <T>(someObject: { bar: T }): T => {
    return someObject.bar
}

const barFoo1 = { bar: "asdf", foo: "fdsa"};
const myBar1: string = foo(barFoo1);

const barFoo2 = { bar: 123, foo: 321};
const myBar2: number = foo(barFoo2);