curring

const sum1=(x:number,y:number)=>{
  return x+y;
}

const sum=(x:number) =>{
  return (y:number)=>{
    return x+y;
  }
}

const sum2= sum(3);
console.log(sum2(4));
console.log(sum(3)(4));

curring function :

only use 1 parameter and return next function