CFP - Docs

all

(predicate: Predicate) => (collection: Collection) => boolean

Test if all entries return truthy

Try It

const gt2 = n => n > 2
const allGt2 = all(gt2)

allGt2([2, 3]) // is false
allGt2([3, 4]) // is true
allGt2({ b: 2, c: 3 }) // is false
allGt2({ c: 3, d: 4 }) // is true
const gt2 = (n: number) => n > 2
const allGt2 = all(gt2)

allGt2([2, 3]) // is false
allGt2([3, 4]) // is true
allGt2({ b: 2, c: 3 }) // is false
allGt2({ c: 3, d: 4 }) // is true

Try It

const gt2 = n => n > 2
const allGt2 = all(gt2)

allGt2([2, 3]) // is false
allGt2([3, 4]) // is true
allGt2({ b: 2, c: 3 }) // is false
allGt2({ c: 3, d: 4 }) // is true
const gt2 = (n: number) => n > 2
const allGt2 = all(gt2)

allGt2([2, 3]) // is false
allGt2([3, 4]) // is true
allGt2({ b: 2, c: 3 }) // is false
allGt2({ c: 3, d: 4 }) // is true

We often want to know if all entries pass a condition. Below, a classroom earns a pizza party if all students score at least a B. Let's see which classrooms get pizza.

Try It

const classroomScores = {
  A: [92, 98, 73],
  B: [95, 83, 88],
}

const gte80 = n => n >= 80
const earnsParty = all(gte80)

const getRoomsEarningParty = compose([keepWhen(earnsParty), Object.keys])
const rooms = getRoomsEarningParty(classroomScores)
console.log(rooms) // is [B]
type ClassroomScores = Record<string, number[]>

const classroomScores: ClassroomScores = {
  A: [92, 98, 73],
  B: [95, 83, 88],
}

const gte80 = (n: number) => n >= 80
const earnsParty = all(gte80)<number[]>

const getRoomsEarningParty = compose([
  keepWhen(earnsParty)<ClassroomScores>,
  Object.keys,
])
const rooms = getRoomsEarningParty(classroomScores)
console.log(rooms) // is [B]

Try It

const classroomScores = {
  A: [92, 98, 73],
  B: [95, 83, 88],
}

const gte80 = n => n >= 80
const earnsParty = all(gte80)

const getRoomsEarningParty = compose([
  keepWhen(earnsParty),
  Object.keys,
])
const rooms = getRoomsEarningParty(
  classroomScores
)
console.log(rooms) // is [B]
type ClassroomScores = Record<string, number[]>

const classroomScores: ClassroomScores = {
  A: [92, 98, 73],
  B: [95, 83, 88],
}

const gte80 = (n: number) => n >= 80
const earnsParty = all(gte80)<number[]>

const getRoomsEarningParty = compose([
  keepWhen(earnsParty)<ClassroomScores>,
  Object.keys,
])
const rooms = getRoomsEarningParty(
  classroomScores
)
console.log(rooms) // is [B]