Typescript ADT.ts

type MyADT = {
    t: "Case1";
    v1: string;
} | {
    t: "Case2";
    v2: string;
    at: number;
} | {
    t: "Case3",
    v2: string
};

const x: MyADT = { t: "Case2", v2: "asdf", at: 4 };

function process(v: MyADT) {
    switch (x.t) {
        case "Case1":
            return console.log(x.v1);
        case "Case2":
            return console.log(x.v2);
        case "Case3":
            return console.log(x.v2);
    }
}

process(x);