CFP - Docs - prependOne

prependOne

(value: any) => (base: array) => array

Prepend a value to an array

Try It

const prependA = prependOne('a')
prependA(['b', 'c']) // is ['a', 'b', 'c']

const prependArrayA = prependOne(['a'])
prependArrayA(['b', 'c']) // is [['a'], 'b', 'c']
const prependA = prependOne('a')
prependA(['b', 'c']) // is ['a', 'b', 'c']

const prependArrayA = prependOne(['a'])
prependArrayA(['b', 'c']) // is [['a'], 'b', 'c']

Try It

const prependA = prependOne('a')
prependA(['b', 'c']) // is ['a', 'b', 'c']

const prependArrayA = prependOne(['a'])
prependArrayA(['b', 'c']) // is [['a'], 'b', 'c']
const prependA = prependOne('a')
prependA(['b', 'c']) // is ['a', 'b', 'c']

const prependArrayA = prependOne(['a'])
prependArrayA(['b', 'c']) // is [['a'], 'b', 'c']

Sometimes we want to prepend an item. Below, we are running a restaurant and have a queue of tickets. New tickets usually get added to the end. Unfortunately, one customer received the wrong order, so we need to quickly remake it. Let's prepend his order to the queue.

Try It

const tickets = [['burger', 'fries'], ['chicken wings', 'salad'], ['soup']]

const tomsOrder = ['chicken wrap', 'cheese curds']
const prependTomsOrder = prependOne(tomsOrder)

const updatedTickets = prependTomsOrder(tickets)
console.log(updatedTickets)
// prints [
//   [chicken wrap, cheese curds]
//   [burger, fries]
//   [chicken wings, salad]
//   [soup]
// ]
const tickets = [['burger', 'fries'], ['chicken wings', 'salad'], ['soup']]

const tomsOrder = ['chicken wrap', 'cheese curds']
const prependTomsOrder = prependOne(tomsOrder)

const updatedTickets = prependTomsOrder(tickets)
console.log(updatedTickets)
// prints [
//   [chicken wrap, cheese curds]
//   [burger, fries]
//   [chicken wings, salad]
//   [soup]
// ]

Try It

const tickets = [
  ['burger', 'fries'],
  ['chicken wings', 'salad'],
  ['soup'],
]

const tomsOrder = ['chicken wrap', 'cheese curds']
const prependTomsOrder = prependOne(tomsOrder)

const updatedTickets = prependTomsOrder(tickets)
console.log(updatedTickets)
// prints [
//   [chicken wrap, cheese curds]
//   [burger, fries]
//   [chicken wings, salad]
//   [soup]
// ]
const tickets = [
  ['burger', 'fries'],
  ['chicken wings', 'salad'],
  ['soup'],
]

const tomsOrder = ['chicken wrap', 'cheese curds']
const prependTomsOrder = prependOne(tomsOrder)

const updatedTickets = prependTomsOrder(tickets)
console.log(updatedTickets)
// prints [
//   [chicken wrap, cheese curds]
//   [burger, fries]
//   [chicken wings, salad]
//   [soup]
// ]