TypeScript-All-In-One(A.R)

Work with destructuring, akin objects:

let foo = {
    a: 123,
    b: 456
};
let {a} = foo;
// a = "hello"; // Would Error: cannot assign `string` to a `number`

and arrays:

const bar = [1, 2];
let [a, b] = bar;
// a = "hello"; // Would Error: cannot assign `string` to a `number`

And if the function parameter can be inferred, so can its destructured properties. For example here we destructure the argument into its a/b members.

type Adder = (numbers: { a: number, b: number }) => number;
function iTakeAnAdder(adder: Adder) {
    return adder({ a: 1, b: 2 });
}
iTakeAnAdder(({a, b}) => { // Types of `a` and `b` are inferred
    // a = "hello"; // Would Error: cannot assign `string` to a `number`
    return a + b;
})