CFP - Docs - discardRange

discardRange

(range: Range) => (sequence: Sequence) => Sequence

Discard a range of indices

Ranges in Common FP are inclusive

Try It

const range = { startIdx: 1, endIdx: 2 }
const discard2ndAnd3rd = discardRange(range)

discard2ndAnd3rd(['a', 'b', 'c', 'd']) // is ['a', 'd']
discard2ndAnd3rd('abcd') // is 'ad'
discard2ndAnd3rd(['a', 'b']) // is ['a']
const range = { startIdx: 1, endIdx: 2 }
const discard2ndAnd3rd = discardRange(range)

discard2ndAnd3rd(['a', 'b', 'c', 'd']) // is ['a', 'd']
discard2ndAnd3rd('abcd') // is 'ad'
discard2ndAnd3rd(['a', 'b']) // is ['a']

Try It

const range = { startIdx: 1, endIdx: 2 }
const discard2ndAnd3rd = discardRange(range)

discard2ndAnd3rd(['a', 'b', 'c', 'd']) // is ['a', 'd']
discard2ndAnd3rd('abcd') // is 'ad'
discard2ndAnd3rd(['a', 'b']) // is ['a']
const range = { startIdx: 1, endIdx: 2 }
const discard2ndAnd3rd = discardRange(range)

discard2ndAnd3rd(['a', 'b', 'c', 'd']) // is ['a', 'd']
discard2ndAnd3rd('abcd') // is 'ad'
discard2ndAnd3rd(['a', 'b']) // is ['a']

Sometimes we want to remove a range of data. Below, we have three weeks of Liz's bowling scores. She can't make it Tuesdays and Wednesdays due to choir, so let's remove those.

Try It

const scores = [
  ['monday', 'tuesday', 'wednesday', 'thursday', 'friday'],
  [188, 0, 0, 202, 156],
  [172, 0, 0, 190, 185],
  [206, 0, 0, 167, 191],
]

const tueAndWed = { startIdx: 1, endIdx: 2 }
const discardAbsentScores = discardRange(tueAndWed)
const discardAllAbsentScores = mapValues(discardAbsentScores)

const updatedScores = discardAllAbsentScores(scores)
console.log(updatedScores)
// is [
//  ['monday', 'thursday', 'friday'],
//  [188, 202, 156],
//  [172, 190, 185],
//  [206, 167, 191],
// ]
type Scores = [string[], ...number[][]]
const scores: Scores = [
  ['monday', 'tuesday', 'wednesday', 'thursday', 'friday'],
  [188, 0, 0, 202, 156],
  [172, 0, 0, 190, 185],
  [206, 0, 0, 167, 191],
]

const tueAndWed = { startIdx: 1, endIdx: 2 }
const discardAbsentScores = discardRange(tueAndWed)<string[] | number[]>
const discardAllAbsentScores = mapValues(discardAbsentScores)<Scores>

const updatedScores = discardAllAbsentScores(scores) as Scores
console.log(updatedScores)
// is [
//  ['monday', 'thursday', 'friday'],
//  [188, 202, 156],
//  [172, 190, 185],
//  [206, 167, 191],
// ]

Try It

const scores = [
  [
    'monday',
    'tuesday',
    'wednesday',
    'thursday',
    'friday',
  ],
  [188, 0, 0, 202, 156],
  [172, 0, 0, 190, 185],
  [206, 0, 0, 167, 191],
]

const tueAndWed = { startIdx: 1, endIdx: 2 }
const discardAbsentScores =
  discardRange(tueAndWed)
const discardAllAbsentScores = mapValues(
  discardAbsentScores
)

const updatedScores =
  discardAllAbsentScores(scores)
console.log(updatedScores)
// is [
//  ['monday', 'thursday', 'friday'],
//  [188, 202, 156],
//  [172, 190, 185],
//  [206, 167, 191],
// ]
type Scores = [string[], ...number[][]]
const scores: Scores = [
  [
    'monday',
    'tuesday',
    'wednesday',
    'thursday',
    'friday',
  ],
  [188, 0, 0, 202, 156],
  [172, 0, 0, 190, 185],
  [206, 0, 0, 167, 191],
]

const tueAndWed = { startIdx: 1, endIdx: 2 }
const discardAbsentScores = discardRange(
  tueAndWed
)<string[] | number[]>
const discardAllAbsentScores = mapValues(
  discardAbsentScores
)<Scores>

const updatedScores = discardAllAbsentScores(
  scores
) as Scores
console.log(updatedScores)
// is [
//  ['monday', 'thursday', 'friday'],
//  [188, 202, 156],
//  [172, 190, 185],
//  [206, 167, 191],
// ]