CFP - Docs - order

order

(compareFn: CompareFn) => (anArray: array) => array

Order an array using a compare function

Try It

const arr = [3, 1, 2]

const ascending = (left, right) => left - right
const orderByAscending = order(ascending)
const orderedArr = orderByAscending(arr)

console.log(orderedArr) // is [1, 2, 3]
const arr = [3, 1, 2]

const ascending = (left: number, right: number) => left - right
const orderByAscending = order(ascending)
const orderedArr = orderByAscending(arr)

console.log(orderedArr) // is [1, 2, 3]

Try It

const arr = [3, 1, 2]

const ascending = (left, right) => left - right
const orderByAscending = order(ascending)
const orderedArr = orderByAscending(arr)

console.log(orderedArr) // is [1, 2, 3]
const arr = [3, 1, 2]

const ascending = (left: number, right: number) =>
  left - right
const orderByAscending = order(ascending)
const orderedArr = orderByAscending(arr)

console.log(orderedArr) // is [1, 2, 3]

Sometimes we want to order an array. Below, we are building a game with an inventory. Players will want to see what's weighing them down, so let's allow them to order by weight.

Try It

const inventory = {
  potions: [
    { name: 'heal', weight: 5 },
    { name: 'cloak', weight: 8 },
    { name: 'attack up', weight: 6 },
  ],
  weapons: [
    { name: 'sword', weight: 10 },
    { name: 'axe', weight: 30 },
    { name: 'wand', weight: 8 },
  ],
}

const byWeightDesc = compareByProp('weight', withNumbersDescending)
const orderByWeightDesc = order(byWeightDesc)
const orderAllByWeightDesc = mapValues(orderByWeightDesc)
const orderedInventory = orderAllByWeightDesc(inventory)

console.log(orderedInventory)
// is {
//   potions: [
//     { name: cloak, weight: 8 }
//     { name: attack up, weight: 6 }
//     { name: heal, weight: 5 }
//   ]
//   weapons: [
//     { name: axe, weight: 30 }
//     { name: sword, weight: 10 }
//     { name: wand, weight: 8 }
//   ]
// }
type Item = {
  name: string
  weight: number
}
type Inventory = Record<string, Item[]>
const inventory: Inventory = {
  potions: [
    { name: 'heal', weight: 5 },
    { name: 'cloak', weight: 8 },
    { name: 'attack up', weight: 6 },
  ],
  weapons: [
    { name: 'sword', weight: 10 },
    { name: 'axe', weight: 30 },
    { name: 'wand', weight: 8 },
  ],
}

const byWeightDesc = compareByProp('weight', withNumbersDescending)<Item>
const orderByWeightDesc = order(byWeightDesc)<Item>
const orderAllByWeightDesc = mapValues(orderByWeightDesc)<Inventory>
const orderedInventory = orderAllByWeightDesc(inventory)

console.log(orderedInventory)
// is {
//   potions: [
//     { name: cloak, weight: 8 }
//     { name: attack up, weight: 6 }
//     { name: heal, weight: 5 }
//   ]
//   weapons: [
//     { name: axe, weight: 30 }
//     { name: sword, weight: 10 }
//     { name: wand, weight: 8 }
//   ]
// }

Try It

const inventory = {
  potions: [
    { name: 'heal', weight: 5 },
    { name: 'cloak', weight: 8 },
    { name: 'attack up', weight: 6 },
  ],
  weapons: [
    { name: 'sword', weight: 10 },
    { name: 'axe', weight: 30 },
    { name: 'wand', weight: 8 },
  ],
}

const byWeightDesc = compareByProp(
  'weight',
  withNumbersDescending
)
const orderByWeightDesc = order(byWeightDesc)
const orderAllByWeightDesc = mapValues(
  orderByWeightDesc
)
const orderedInventory =
  orderAllByWeightDesc(inventory)

console.log(orderedInventory)
// is {
//   potions: [
//     { name: cloak, weight: 8 }
//     { name: attack up, weight: 6 }
//     { name: heal, weight: 5 }
//   ]
//   weapons: [
//     { name: axe, weight: 30 }
//     { name: sword, weight: 10 }
//     { name: wand, weight: 8 }
//   ]
// }
type Item = {
  name: string
  weight: number
}
type Inventory = Record<string, Item[]>
const inventory: Inventory = {
  potions: [
    { name: 'heal', weight: 5 },
    { name: 'cloak', weight: 8 },
    { name: 'attack up', weight: 6 },
  ],
  weapons: [
    { name: 'sword', weight: 10 },
    { name: 'axe', weight: 30 },
    { name: 'wand', weight: 8 },
  ],
}

const byWeightDesc = compareByProp(
  'weight',
  withNumbersDescending
)<Item>
const orderByWeightDesc = order(
  byWeightDesc
)<Item>
const orderAllByWeightDesc = mapValues(
  orderByWeightDesc
)<Inventory>
const orderedInventory =
  orderAllByWeightDesc(inventory)

console.log(orderedInventory)
// is {
//   potions: [
//     { name: cloak, weight: 8 }
//     { name: attack up, weight: 6 }
//     { name: heal, weight: 5 }
//   ]
//   weapons: [
//     { name: axe, weight: 30 }
//     { name: sword, weight: 10 }
//     { name: wand, weight: 8 }
//   ]
// }