Optional property on the first element of an array but required on the others

Fil*_*ský 5

您可以像这样使用可变元组类型（Typescript 4.0+）：

interface First {
    label?: string;
    value: string;
}

interface Item {
    label: string;
    value: string;
}

type Items = [First, ...Item[]];

const array: Items = [
    {
        value: 'Value1',
    },
    {
        label: 'Label2',
        value: 'Value2',
    },
    {
        label: 'Label3',
        value: 'Value3',
    },
    {
        label: 'Label4',
        value: 'Value4',
    },
];