Utilities for manipulating and validating numeric types in TypeScript. These types allow you to check parity, sign, get absolute values, truncate decimals, and generate number ranges at the type level.

Number Utilities

Installation

npm i -D @halvaradop/ts-utility-types

Usage

import type { IsOdd, IsEven, Absolute } from "@halvaradop/ts-utility-types/numbers"

import type * as Numbers from "@halvaradop/ts-utility-types/numbers"

type Result = Numbers.Absolute
IsEven
IsNegative
IsOdd
IsPositive
NumberRange
Trunc

`IsOdd<T>`

Checks if a number is odd. Returns true if the number is odd, false otherwise.

Argument	Type	Description
`T`	`number`	The number to check.

Related: IsEven

import type { IsOdd } from "@halvaradop/ts-utility-types/numbers"

type CheckOdd = IsOdd<2023>       
type CheckOdd = true

type CheckEven = IsOdd<2024>       
type CheckEven = false

type CheckOne = IsOdd<1>       
type CheckOne = true

`IsEven<T>`

Checks if a number is even. Returns true if the number is even, false otherwise.

Argument	Type	Description
`T`	`number`	The number to check.

Related: IsOdd

import type { IsEven } from "@halvaradop/ts-utility-types/numbers"

type CheckEven = IsEven<2024>       
type CheckEven = true

type CheckOdd = IsEven<2023>       
type CheckOdd = false

type CheckZero = IsEven<0>       
type CheckZero = true

`IsNegative<T>`

Checks if a number is negative. Returns true if the number is less than zero, false otherwise.

Argument	Type	Description
`T`	`number`	The number to check.

Related: IsPositive

import type { IsNegative } from "@halvaradop/ts-utility-types/numbers"

type CheckNegative = IsNegative<-2024>         
type CheckNegative = true

type CheckPositive = IsNegative<2024>         
type CheckPositive = false

type CheckZero = IsNegative<0>       
type CheckZero = false

`IsPositive<T>`

Checks if a number is positive. Returns true if the number is greater than zero, false otherwise.

Argument	Type	Description
`T`	`number`	The number to check.

Related: IsNegative

import type { IsPositive } from "@halvaradop/ts-utility-types/numbers"

type CheckPositive = IsPositive<2024>         
type CheckPositive = true

type CheckNegative = IsPositive<-2024>         
type CheckNegative = false

type CheckZero = IsPositive<0>       
type CheckZero = true

Compile-Time Operations

These utilities work with literal numeric types at compile-time. They don't perform runtime operations.

`Absolute<Expression>`

Returns the absolute value of a number, string, or bigint as a string.

Argument	Type	Description
`Expression`	`number` \| `string` \| `bigint`	The value to get the absolute value of.

import type { Absolute } from "@halvaradop/ts-utility-types/numbers"

type PositiveNumber = Absolute<2024>          
type PositiveNumber = "2024"

type PositiveString = Absolute<"-2024">          
type PositiveString = "2024"

type PositiveBigint = Absolute<-123n>          
type PositiveBigint = "123"

`Trunc<Math>`

Truncates a number to its integer part, removing any decimal portion.

Argument	Type	Description
`Math`	`string` \| `number` \| `bigint`	The number to truncate.

import type { Trunc } from "@halvaradop/ts-utility-types/numbers"

type Truncated = Trunc<3.14>       
type Truncated = "3"

type TruncatedNegative = Trunc<-2.99>           
type TruncatedNegative = "-2"

type TruncatedString = Trunc<"5.67">          
type TruncatedString = "5"

`NumberRange<Low, High>`

Generates a union type of numeric literals from Low to High (inclusive). Only non-negative values are supported; if either Low or High is negative, the result is never.

Argument	Type	Description
`Low`	`number`	The starting number of the range (inclusive).
`High`	`number`	The ending number of the range (inclusive).

Behavior:

import type { NumberRange } from "@halvaradop/ts-utility-types/numbers"

type Range1to5 = NumberRange<1, 5>       
type Range1to5 = 1 | 5 | 2 | 3 | 4

type Range3to7 = NumberRange<3, 7>       
type Range3to7 = 5 | 3 | 4 | 7 | 6

type InvalidRange = NumberRange<-1, 5>         
type InvalidRange = never

Number Utilities

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