Hey @lveillard 👋 I agree, being able to filter in a more dynamic way would be great! I'm hesitant to follow the path that lodash took. Honestly, the whole By suffix always confused me. What if we just call it filter?

const filter = <T>(
  obj: T,
  fn: (k: keyof T, v: T) => boolean
): Partial<T>

Why not! I tend to call these oFilter, oMap... in order to make them obviously different to filter(), map()...

The o for "object" as they are object to object functions.

I always imagined these working natively like this:

{a:1, b:3}.filter((k,v)=>v>2)
// result: {b:3}

Funny, I call them filtero and mapo 🍻

This is a pretty simple one, would you be interested in implementing it?

😂
Now that i think about it, is just FilterEntries(), isnt? If we keep current naming logic 🤔

And right now i'm figthing against some deadlines but happy to collaborate after that!

I'm struggling a bit with the Filter function's types but i added a find function.
#178

For the filter i'm here:

export const oFilter = <RemovedKeys extends string, T extends Record<string|number|symbol,any>>(obj: T, fn: (k: keyof T, v:any)=>boolean):Omit<T, RemovedKeys> => Object.fromEntries(Object.entries(obj).filter(([k,v])=> fn(k,v)))

but i'm not there yet

function OFilter<T, K extends keyof T>(obj: T, fn: (key: K, value: T[K]) => boolean): Pick<T, K> {
  return Object.fromEntries(Object.entries(obj).filter(([k,v]) => fn(k,v))) as Pick<T, K>;
}

What about this one?

I think the return type you want is Partial<T>, I don't think you'll be able to type the specific keys that will be returned since it's dynamic at runtime.

Question, you're saying filter here but your PR says find. Did I miss something there?

Yay, they are two different functions but im not sure about the naming.

Find gets only property and returns directly its value
Filter shakes an object by a fn(k, v) and is the one that indeed could be typed as Partial

For the record, radash shake can behave as lodash omitBy (which is alike pickBy, but inverted condition)

Any progress on this?