number zero

@nick/is/number/zero

isZero

Signature

function isZero<N = number>(it: N): it is Zero<N>;

Checks if a given value is a zero number. This includes both positive and negative zero. It also supports numbers and numeric strings.

• To check exclusively for -0, use isNegativeZero instead.
• To check exclusively for +0 (meaning zero, but not negative zero), use isPositiveZero instead.

Category

Numbers

isZero

Signature

function isZero(it: unknown): it is Zero;

Checks if a given value is a zero number. This includes both positive and negative zero. It also supports numbers and numeric strings.

• To check exclusively for -0, use isNegativeZero instead.
• To check exclusively for +0 (meaning zero, but not negative zero), use isPositiveZero instead.

Category

Numbers

MaybeZero

Signature

export type MaybeZero<N = number> = Cast<N, MAYBE_ZERO>;

Casts a value into a partial zero type. If the value is not a number, it will resolve to never.

Type Parameters

• N (default: number)

---

Category

Numbers

Examples

import { isZero, type MaybeZero } from "jsr:@type/number";

let x = 0 as MaybeZero, y = 1;

if (isZero(x)) {
  console.log(x);
} else {
  console.log(y);
}

y = 0; // <- No error! (this is the main difference from `Zero`)

Zero

Signature

export type Zero<N = number> = Cast<N, ZERO>;

Casts a value into a zero type. If the value is not a number, it will resolve to never.

Type Parameters

• N (default: number)

---

Category

Numbers

Examples

import { isZero, type Zero } from "jsr:@type/number/zero";

let x = 0 as Zero, y = 1;

if (isZero(x)) {
  console.log(x);
} else {
  console.log(y);
}

// This will raise a TypeScript compiler error:
x = 1; // <- TS2322 Type '1' is not assignable to type 'Zero'.