Typescript:keyof

 type Hero = {

name: string,

power: string,

age: number

}

type HeroKeys = keyof Hero //will be name | power | age

//it will be same as

//type HeroKeys = "name" | "power" | "age"

function getPropery(obj: Hero, key: HeroKeys) {

return obj[key]

}

const myHero: Hero = {

name: "SuperCoder",

power: "Code Manipulation",

age: 30

}

const heroName = getPropery(myHero,'age')

console.log(heroName);