rest-spread-tricks-05.js

const user1 = {
  id: 100,
  name: 'Howard Moon',
  password: 'Password!'
}
const removeProperty = prop => ({ [prop]: _, ...rest }) => rest
//                     ----       ------
//                          \   /
//                dynamic destructuring

const removePassword = removeProperty('password')
const removeId = removeProperty('id')

removePassword(user1) //=> { id: 100, name: 'Howard Moon' }
removeId(user1) //=> { name: 'Howard Moon', password: 'Password!' }

What does the underscore on line 6 actually stands for?

@exoslav, he's assigning the computed [prop] to a new variable _ which is being ignore (that's the purpose here). Basically he's naming a property from the destructured object.

This gist is written for 7 Tricks with Resting and Spreading JavaScript Objects

@meendoo, Does that mean he could have also just used ({ [prop], ...rest }) as well, or is it required to put the whole property structure using a dummy value (_) in order to use a computed property?

@dv, actually you can substitute _ with any valid variable name. The idea here is to take the [prop] of an object, encapsulate it inside the function and return only rest.