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fp-ts-contrib

Array overview

Added in v0.1.0

Table of contents

utils

alignArray

Align instance for Array.

Signature

export declare const alignArray: Align1<'Array'>

Added in v0.1.0

lpadZip

Takes two arrays and returns an array of corresponding pairs. If the left input array is short, it will be padded using none.

It is similar to zip, but it doesn’t discard elements when the left input array is shorter than the right.

Signature

export declare const lpadZip: <A, B>(xs: A[], ys: B[]) => [Option<A>, B][]

Example

import { some, none } from 'fp-ts/Option'
import { lpadZip } from 'fp-ts-contrib/Align/Array'

assert.deepStrictEqual(lpadZip([1, 2], ['a', 'b', 'c']), [
  [some(1), 'a'],
  [some(2), 'b'],
  [none, 'c'],
])
assert.deepStrictEqual(lpadZip([1, 2, 3], ['a', 'b']), [
  [some(1), 'a'],
  [some(2), 'b'],
])

Added in v0.1.0

lpadZipWith

Apply a function to pairs of elements at the same index in two arrays, collecting the results in a new array. If the left input array is short, it will be padded using none.

It is similar to zipWith, but it doesn’t discard elements when the left input array is shorter than the right.

Signature

export declare const lpadZipWith: <A, B, C>(xs: A[], ys: B[], f: (a: Option<A>, b: B) => C) => C[]

Example

import * as O from 'fp-ts/Option'
import { lpadZipWith } from 'fp-ts-contrib/Align/Array'
import { pipe } from 'fp-ts/function'

const f = (ma: O.Option<number>, b: string) =>
  pipe(
    ma,
    O.fold(
      () => '*',
      (a) => a.toString()
    )
  ) + b
assert.deepStrictEqual(lpadZipWith([1, 2, 3], ['a', 'b', 'c', 'd'], f), ['1a', '2b', '3c', '*d'])
assert.deepStrictEqual(lpadZipWith([1, 2, 3, 4], ['a', 'b', 'c'], f), ['1a', '2b', '3c'])

Added in v0.1.0

rpadZip

Takes two arrays and returns an array of corresponding pairs. If the right input array is short, it will be padded using none.

It is similar to zip, but it doesn’t discard elements when the right input array is shorter than the left.

Signature

export declare const rpadZip: <A, B>(xs: A[], ys: B[]) => [A, Option<B>][]

Example

import { some, none } from 'fp-ts/Option'
import { rpadZip } from 'fp-ts-contrib/Align/Array'

assert.deepStrictEqual(rpadZip([1, 2, 3], ['a', 'b']), [
  [1, some('a')],
  [2, some('b')],
  [3, none],
])
assert.deepStrictEqual(rpadZip([1, 2], ['a', 'b', 'c']), [
  [1, some('a')],
  [2, some('b')],
])

Added in v0.1.0

rpadZipWith

Apply a function to pairs of elements at the same index in two arrays, collecting the results in a new array. If the right input array is short, it will be padded using none.

It is similar to zipWith, but it doesn’t discard elements when the right input array is shorter than the left.

Signature

export declare const rpadZipWith: <A, B, C>(xs: A[], ys: B[], f: (a: A, b: Option<B>) => C) => C[]

Example

import { Option, getOrElse } from 'fp-ts/Option'
import { rpadZipWith } from 'fp-ts-contrib/Align/Array'

const f = (a: number, mb: Option<string>) => a.toString() + getOrElse(() => '*')(mb)
assert.deepStrictEqual(rpadZipWith([1, 2, 3, 4], ['a', 'b', 'c'], f), ['1a', '2b', '3c', '4*'])
assert.deepStrictEqual(rpadZipWith([1, 2, 3], ['a', 'b', 'c', 'd'], f), ['1a', '2b', '3c'])

Added in v0.1.0