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core

Number overview

This module provides utility functions and type class instances for working with the number type in TypeScript. It includes functions for basic arithmetic operations, as well as type class instances for Equivalence, Order, Semigroup, and Monoid.

Added in v1.0.0

Table of contents

guards

isNumber

Tests if a value is a number.

Signature

export declare const isNumber: (input: unknown) => input is number

Example

import { isNumber } from '@fp-ts/core/Number'

assert.deepStrictEqual(isNumber(2), true)
assert.deepStrictEqual(isNumber('2'), false)

Added in v1.0.0

instances

Bounded

Signature

export declare const Bounded: bounded.Bounded<number>

Added in v1.0.0

Equivalence

Signature

export declare const Equivalence: equivalence.Equivalence<number>

Added in v1.0.0

MonoidMax

A Monoid that uses the maximum between two values.

The empty value is Infinity.

Signature

export declare const MonoidMax: monoid.Monoid<number>

Example

import { MonoidMax } from '@fp-ts/core/Number'

assert.deepStrictEqual(MonoidMax.combine(2, 3), 3)
assert.deepStrictEqual(MonoidMax.combine(2, MonoidMax.empty), 2)

Added in v1.0.0

MonoidMin

A Monoid that uses the minimum between two values.

The empty value is -Infinity.

Signature

export declare const MonoidMin: monoid.Monoid<number>

Example

import { MonoidMin } from '@fp-ts/core/Number'

assert.deepStrictEqual(MonoidMin.combine(2, 3), 2)
assert.deepStrictEqual(MonoidMin.combine(2, MonoidMin.empty), 2)

Added in v1.0.0

MonoidMultiply

number monoid under multiplication.

The empty value is 1.

Signature

export declare const MonoidMultiply: monoid.Monoid<number>

Example

import { MonoidMultiply } from '@fp-ts/core/Number'

assert.deepStrictEqual(MonoidMultiply.combine(2, 3), 6)
assert.deepStrictEqual(MonoidMultiply.combine(2, MonoidMultiply.empty), 2)

Added in v1.0.0

MonoidSum

number monoid under addition.

The empty value is 0.

Signature

export declare const MonoidSum: monoid.Monoid<number>

Example

import { MonoidSum } from '@fp-ts/core/Number'

assert.deepStrictEqual(MonoidSum.combine(2, 3), 5)
assert.deepStrictEqual(MonoidSum.combine(2, MonoidSum.empty), 2)

Added in v1.0.0

Order

Signature

export declare const Order: order.Order<number>

Added in v1.0.0

SemigroupMax

A Semigroup that uses the maximum between two values.

Signature

export declare const SemigroupMax: semigroup.Semigroup<number>

Example

import { SemigroupMax } from '@fp-ts/core/Number'

assert.deepStrictEqual(SemigroupMax.combine(2, 3), 3)

Added in v1.0.0

SemigroupMin

A Semigroup that uses the minimum between two values.

Signature

export declare const SemigroupMin: semigroup.Semigroup<number>

Example

import { SemigroupMin } from '@fp-ts/core/Number'

assert.deepStrictEqual(SemigroupMin.combine(2, 3), 2)

Added in v1.0.0

SemigroupMultiply

number semigroup under multiplication.

Signature

export declare const SemigroupMultiply: semigroup.Semigroup<number>

Example

import { SemigroupMultiply } from '@fp-ts/core/Number'

assert.deepStrictEqual(SemigroupMultiply.combine(2, 3), 6)

Added in v1.0.0

SemigroupSum

number semigroup under addition.

Signature

export declare const SemigroupSum: semigroup.Semigroup<number>

Example

import { SemigroupSum } from '@fp-ts/core/Number'

assert.deepStrictEqual(SemigroupSum.combine(2, 3), 5)

Added in v1.0.0

math

decrement

Decrements a number by 1.

Signature

export declare const decrement: (n: number) => number

Example

import { decrement } from '@fp-ts/core/Number'

assert.deepStrictEqual(decrement(3), 2)

Added in v1.0.0

divide

Provides a division operation on numbers.

Signature

export declare const divide: { (that: number): (self: number) => number; (self: number, that: number): number }

Example

import { divide } from '@fp-ts/core/Number'

assert.deepStrictEqual(divide(6, 3), 2)

Added in v1.0.0

increment

Returns the result of adding 1 to a given number.

Signature

export declare const increment: (n: number) => number

Example

import { increment } from '@fp-ts/core/Number'

assert.deepStrictEqual(increment(2), 3)

Added in v1.0.0

multiply

Provides a multiplication operation on numbers.

Signature

export declare const multiply: { (that: number): (self: number) => number; (self: number, that: number): number }

Example

import { multiply } from '@fp-ts/core/Number'

assert.deepStrictEqual(multiply(2, 3), 6)

Added in v1.0.0

multiplyAll

Takes an Iterable of numbers and returns their multiplication as a single number.

Signature

export declare const multiplyAll: (collection: Iterable<number>) => number

Example

import { multiplyAll } from '@fp-ts/core/Number'

assert.deepStrictEqual(multiplyAll([2, 3, 4]), 24)

Added in v1.0.0

remainder

Returns the remainder left over when one operand is divided by a second operand.

It always takes the sign of the dividend.

Signature

export declare const remainder: { (divisor: number): (self: number) => number; (self: number, divisor: number): number }

Example

import { remainder } from '@fp-ts/core/Number'

assert.deepStrictEqual(remainder(2, 2), 0)
assert.deepStrictEqual(remainder(3, 2), 1)
assert.deepStrictEqual(remainder(-4, 2), -0)

Added in v1.0.0

sign

Determines the sign of a given number.

Signature

export declare const sign: (n: number) => Ordering

Example

import { sign } from '@fp-ts/core/Number'

assert.deepStrictEqual(sign(-5), -1)
assert.deepStrictEqual(sign(0), 0)
assert.deepStrictEqual(sign(5), 1)

Added in v1.0.0

subtract

Provides a subtraction operation on numbers.

Signature

export declare const subtract: { (that: number): (self: number) => number; (self: number, that: number): number }

Example

import { subtract } from '@fp-ts/core/Number'

assert.deepStrictEqual(subtract(2, 3), -1)

Added in v1.0.0

sum

Provides an addition operation on numbers.

Signature

export declare const sum: { (that: number): (self: number) => number; (self: number, that: number): number }

Example

import { sum } from '@fp-ts/core/Number'

assert.deepStrictEqual(sum(2, 3), 5)

Added in v1.0.0

sumAll

Takes an Iterable of numbers and returns their sum as a single number.

Signature

export declare const sumAll: (collection: Iterable<number>) => number

Example

import { sumAll } from '@fp-ts/core/Number'

assert.deepStrictEqual(sumAll([2, 3, 4]), 9)

Added in v1.0.0

predicates

between

Checks if a number is between a minimum and maximum value (inclusive).

Signature

export declare const between: {
  (minimum: number, maximum: number): (self: number) => boolean
  (self: number, minimum: number, maximum: number): boolean
}

Example

import { between } from '@fp-ts/core/Number'

assert.deepStrictEqual(between(0, 5)(3), true)
assert.deepStrictEqual(between(0, 5)(-1), false)
assert.deepStrictEqual(between(0, 5)(6), false)

Added in v1.0.0

greaterThan

Returns true if the first argument is greater than the second, otherwise false.

Signature

export declare const greaterThan: { (that: number): (self: number) => boolean; (self: number, that: number): boolean }

Example

import { greaterThan } from '@fp-ts/core/Number'

assert.deepStrictEqual(greaterThan(2, 3), false)
assert.deepStrictEqual(greaterThan(3, 3), false)
assert.deepStrictEqual(greaterThan(4, 3), true)

Added in v1.0.0

greaterThanOrEqualTo

Returns a function that checks if a given number is greater than or equal to the provided one.

Signature

export declare const greaterThanOrEqualTo: {
  (that: number): (self: number) => boolean
  (self: number, that: number): boolean
}

Example

import { greaterThanOrEqualTo } from '@fp-ts/core/Number'

assert.deepStrictEqual(greaterThanOrEqualTo(2, 3), false)
assert.deepStrictEqual(greaterThanOrEqualTo(3, 3), true)
assert.deepStrictEqual(greaterThanOrEqualTo(4, 3), true)

Added in v1.0.0

lessThan

Returns true if the first argument is less than the second, otherwise false.

Signature

export declare const lessThan: { (that: number): (self: number) => boolean; (self: number, that: number): boolean }

Example

import { lessThan } from '@fp-ts/core/Number'

assert.deepStrictEqual(lessThan(2, 3), true)
assert.deepStrictEqual(lessThan(3, 3), false)
assert.deepStrictEqual(lessThan(4, 3), false)

Added in v1.0.0

lessThanOrEqualTo

Returns a function that checks if a given number is less than or equal to the provided one.

Signature

export declare const lessThanOrEqualTo: {
  (that: number): (self: number) => boolean
  (self: number, that: number): boolean
}

Example

import { lessThanOrEqualTo } from '@fp-ts/core/Number'

assert.deepStrictEqual(lessThanOrEqualTo(2, 3), true)
assert.deepStrictEqual(lessThanOrEqualTo(3, 3), true)
assert.deepStrictEqual(lessThanOrEqualTo(4, 3), false)

Added in v1.0.0

utils

clamp

Restricts the given number to be within the range specified by the minimum and maximum values.

  • If the number is less than the minimum value, the function returns the minimum value.
  • If the number is greater than the maximum value, the function returns the maximum value.
  • Otherwise, it returns the original number.

Signature

export declare const clamp: {
  (minimum: number, maximum: number): (self: number) => number
  (self: number, minimum: number, maximum: number): number
}

Example

import { clamp } from '@fp-ts/core/Number'

assert.deepStrictEqual(clamp(0, 5)(3), 3)
assert.deepStrictEqual(clamp(0, 5)(-1), 0)
assert.deepStrictEqual(clamp(0, 5)(6), 5)

Added in v1.0.0

max

Returns the maximum between two numbers.

Signature

export declare const max: { (that: number): (self: number) => number; (self: number, that: number): number }

Example

import { max } from '@fp-ts/core/Number'

assert.deepStrictEqual(max(2, 3), 3)

Added in v1.0.0

min

Returns the minimum between two numbers.

Signature

export declare const min: { (that: number): (self: number) => number; (self: number, that: number): number }

Example

import { min } from '@fp-ts/core/Number'

assert.deepStrictEqual(min(2, 3), 2)

Added in v1.0.0