pointlessFunction.ts

const pointlessFunction = (input: string): string => {
    let oneToThreeObj = {
        1: "one", 2: "two", 3: "three"
    };
    let output = "";
    [...input].forEach((char)=>{
      // ts-ignore
        if (char in oneToThreeObj) output+=oneToThreeObj[char];
    });

    return output;
}

console.log(pointlessFunction("t1k3h2k4"));