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Monoid

Constructors​

Model​

Utilities​

Constructors​

max​

Get a monoid where concat will return the maximum, based on the provided bounded order.

The empty value is the bottom value.

Signature​

export declare const max: <A>(B: Bounded<A>) => Monoid<A>

Details​

  • Added in 0.1.0

Example​

import * as N from '@fp-tx/core/number'
import * as M from '@fp-tx/core/Monoid'

const M1 = M.max(N.Bounded)

assert.deepStrictEqual(M1.concat(1, 2), 2)

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

min​

Get a monoid where concat will return the minimum, based on the provided bounded order.

The empty value is the top value.

Signature​

export declare const min: <A>(B: Bounded<A>) => Monoid<A>

Details​

  • Added in 0.1.0

Example​

import * as N from '@fp-tx/core/number'
import * as M from '@fp-tx/core/Monoid'

const M1 = M.min(N.Bounded)

assert.deepStrictEqual(M1.concat(1, 2), 1)

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

Model​

Monoid​

Signature​

export interface Monoid<A> extends Se.Semigroup<A> {
  readonly empty: A
}

Details​

  • Added in 0.1.0

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

Utilities​

concatAll​

Given a sequence of as, concat them and return the total.

If as is empty, return the monoid empty value.

Signature​

export declare const concatAll: <A>(M: Monoid<A>) => (as: readonly A[]) => A

Details​

  • Added in 0.1.0

Example​

import { concatAll } from '@fp-tx/core/Monoid'
import * as N from '@fp-tx/core/number'

assert.deepStrictEqual(concatAll(N.MonoidSum)([1, 2, 3]), 6)
assert.deepStrictEqual(concatAll(N.MonoidSum)([]), 0)

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

fold​

Use concatAll instead.

Signature​

export declare const fold: <A>(M: Monoid<A>) => (as: readonly A[]) => A

Details​

  • Added in 0.1.0
  • Deprecated

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

getDualMonoid​

Use reverse instead.

Signature​

export declare const getDualMonoid: <A>(M: Monoid<A>) => Monoid<A>

Details​

  • Added in 0.1.0
  • Deprecated

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

getEndomorphismMonoid​

Use getEndomorphismMonoid instead.

Note. The execution order in getEndomorphismMonoid is reversed.

Signature​

export declare const getEndomorphismMonoid: <A = never>() => Monoid<Endomorphism<A>>

Details​

  • Added in 0.1.0
  • Deprecated

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

getFunctionMonoid​

Use getMonoid instead.

Signature​

export declare const getFunctionMonoid: <M>(M: Monoid<M>) => <A = never>() => Monoid<(a: A) => M>

Details​

  • Added in 0.1.0
  • Deprecated

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

getJoinMonoid​

Use max instead.

Signature​

export declare const getJoinMonoid: <A>(B: Bounded<A>) => Monoid<A>

Details​

  • Added in 0.1.0
  • Deprecated

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

getMeetMonoid​

Use min instead.

Signature​

export declare const getMeetMonoid: <A>(B: Bounded<A>) => Monoid<A>

Details​

  • Added in 0.1.0
  • Deprecated

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

getStructMonoid​

Use struct instead.

Signature​

export declare const getStructMonoid: <O extends ReadonlyRecord<string, any>>(monoids: {
  [K in keyof O]: Monoid<O[K]>
}) => Monoid<O>

Details​

  • Added in 0.1.0
  • Deprecated

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

getTupleMonoid​

Use tuple instead.

Signature​

export declare const getTupleMonoid: <T extends ReadonlyArray<Monoid<any>>>(
  ...monoids: T
) => Monoid<{
  [K in keyof T]: T[K] extends Se.Semigroup<infer A> ? A : never
}>

Details​

  • Added in 0.1.0
  • Deprecated

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

monoidAll​

Use MonoidAll instead.

Signature​

export declare const monoidAll: Monoid<boolean>

Details​

  • Added in 0.1.0
  • Deprecated

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

monoidAny​

Use MonoidAny instead.

Signature​

export declare const monoidAny: Monoid<boolean>

Details​

  • Added in 0.1.0
  • Deprecated

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

monoidProduct​

Use MonoidProduct instead.

Signature​

export declare const monoidProduct: Monoid<number>

Details​

  • Added in 0.1.0
  • Deprecated

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

monoidString​

Use Monoid instead.

Signature​

export declare const monoidString: Monoid<string>

Details​

  • Added in 0.1.0
  • Deprecated

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

monoidSum​

Use MonoidSum instead.

Signature​

export declare const monoidSum: Monoid<number>

Details​

  • Added in 0.1.0
  • Deprecated

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

monoidVoid​

Use Monoid instead.

Signature​

export declare const monoidVoid: Monoid<void>

Details​

  • Added in 0.1.0
  • Deprecated

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

reverse​

The dual of a Monoid, obtained by swapping the arguments of concat.

Signature​

export declare const reverse: <A>(M: Monoid<A>) => Monoid<A>

Details​

  • Added in 0.1.0

Example​

import { reverse } from '@fp-tx/core/Monoid'
import * as S from '@fp-tx/core/string'

assert.deepStrictEqual(reverse(S.Monoid).concat('a', 'b'), 'ba')

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

struct​

Given a struct of monoids returns a monoid for the struct.

Signature​

export declare const struct: <A>(monoids: { [K in keyof A]: Monoid<A[K]> }) => Monoid<{
  readonly [K_1 in keyof A]: A[K_1]
}>

Details​

  • Added in 0.1.0

Example​

import { struct } from '@fp-tx/core/Monoid'
import * as N from '@fp-tx/core/number'

interface Point {
  readonly x: number
  readonly y: number
}

const M = struct<Point>({
  x: N.MonoidSum,
  y: N.MonoidSum,
})

assert.deepStrictEqual(M.concat({ x: 1, y: 2 }, { x: 3, y: 4 }), { x: 4, y: 6 })

License​

  • MIT – Copyright (c) 2017-present Giulio Canti

tuple​

Given a tuple of monoids returns a monoid for the tuple.

Signature​

export declare const tuple: <A extends readonly unknown[]>(
  ...monoids: { [K in keyof A]: Monoid<A[K]> }
) => Monoid<Readonly<A>>

Details​

  • Added in 0.1.0

Example​

import { tuple } from '@fp-tx/core/Monoid'
import * as B from '@fp-tx/core/boolean'
import * as N from '@fp-tx/core/number'
import * as S from '@fp-tx/core/string'

const M1 = tuple(S.Monoid, N.MonoidSum)
assert.deepStrictEqual(M1.concat(['a', 1], ['b', 2]), ['ab', 3])

const M2 = tuple(S.Monoid, N.MonoidSum, B.MonoidAll)
assert.deepStrictEqual(M2.concat(['a', 1, true], ['b', 2, false]), ['ab', 3, false])

License​

  • MIT – Copyright (c) 2017-present Giulio Canti