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Magma

Model​

Utilities​

Model​

Magma​

Signature​

export interface Magma<A> {
  readonly concat: (x: A, y: A) => 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 provided startWith value.

Signature​

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

Details​

  • Added in 0.1.0

Example​

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

const subAll = concatAll(N.MagmaSub)(0)

assert.deepStrictEqual(subAll([1, 2, 3]), -6)

License​

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

endo​

Signature​

export declare const endo: <A>(f: Endomorphism<A>) => (M: Magma<A>) => Magma<A>

Details​

  • Added in 0.1.0

License​

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

filterFirst​

Signature​

export declare const filterFirst: <A>(predicate: Predicate<A>) => (M: Magma<A>) => Magma<A>

Details​

  • Added in 0.1.0

License​

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

filterSecond​

Signature​

export declare const filterSecond: <A>(predicate: Predicate<A>) => (M: Magma<A>) => Magma<A>

Details​

  • Added in 0.1.0

License​

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

reverse​

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

Signature​

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

Details​

  • Added in 0.1.0

Example​

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

const subAll = concatAll(reverse(N.MagmaSub))(0)

assert.deepStrictEqual(subAll([1, 2, 3]), 2)

License​

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