Discussion on: Useful JS functions you aren't using: Array.filter

[Aaron Eiche]

This is a really excellent point Andrew, and something I totally missed while I was writing it. Thank you for the information and examples!

[Victor Dupuy]

For the record, it's also possible by spreading the object, although it won't work everywhere at the moment, depending on your ES version:

students
  .map(s => ({...s, age: s.age + 1}))
  .filter(s => s.age < 12)
  .forEach(s => console.log(s))

[Tjin]

Clean it even more by extracting callbacks

const addYearToAge = person => ({...person, age: person.age + 1})
const isUnderTwelve = person => person.age < 12

students
  .map(addYearToAge)
  .filter(isUnderTwelve)
  .forEach(console.log)

[Victor Dupuy]

It's beautiful :O