jegj
3/19/2019 - 1:16 PM

Javascript Object Tricks

Basic common tricks based on https://blog.bitsrc.io/6-tricks-with-resting-and-spreading-javascript-objects-68d585bdc83

remove_property.js
content_copyfile_download
const noPassword = ({ password, ...rest }) => rest
const user = {
  id: 100,
  name: 'Howard Moon',
  password: 'Password!'
}

noPassword(user) //=> { id: 100, name: 'Howard moon' }

// https://gist.github.com/joelnet/eee51eee3472bff08ffd064c8ddce202
dynamically_exclude_properties.js
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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!' }

//https://gist.github.com/joelnet/d8ef09c15d83485cf684e98ca1e55735#file-rest-spread-tricks-05-js
default_values.js
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const user2 = {
  id: 200,
  name: 'Vince Noir'
}

const user4 = {
  id: 400,
  name: 'Bollo',
  quotes: ["I've got a bad feeling about this..."]
}

const setDefaults = ({ quotes = [], ...object}) =>
  ({ ...object, quotes })

setDefaults(user2)
//=> { id: 200, name: 'Vince Noir', quotes: [] }

setDefaults(user4)
//=> {
//=>   id: 400,
//=>   name: 'Bollo',
//=>   quotes: ["I've got a bad feeling about this..."]
//=> }
// https://gist.github.com/joelnet/1abc665c56bf94fcf7152642844a9ac9#file-rest-spread-tricks-07-js