TypeScript Type-safe Omit Function

Question

I want to replicate lodash\'s _.omit function in plain typescript. omit should return an object with certain properties removed specified via parameter

Answer 1

The accepted answer from Nurbol above is probably the more typed version, but here is what I am doing in my utils-min.

It uses the typescript built-in Omit and is designed to only support string key names. (still need to loosen up the Set to Set, but everything else seems to work nicely)

export function omit>(obj: T, ...keys: K[]): Omit {
  let ret: any = {};
  const excludeSet: Set = new Set(keys); 
  // TS-NOTE: Set makes the obj[key] type check fail. So, loosing typing here. 

  for (let key in obj) {
    if (!excludeSet.has(key)) {
      ret[key] = obj[key];
    }
  }
  return ret;
}