Decrement.md

typelab / utils / Decrement

type Decrement<N> = N extends number ? number extends N ? number : N extends 0 ? -1 : `${N}` extends `-${infer WholeNumber}` ? ParseFloatNegative<_Increment<WholeNumber>> : `${N}` extends `0.${infer Fraction}` ? ParseFloat<`-0.${Fraction}`> : ParseFloat<_Decrement<`${N}`>> : N extends bigint ? bigint extends N ? bigint : N extends 0n ? -1n : `${N}` extends `-${infer WholeNumber}` ? ParseBigIntNegative<_Increment<WholeNumber>> : ParseBigInt<_Decrement<`${N}`>> : never;

Decrements a given number or bigint by 1.

Type Parameters

Type Parameter	Description
N extends number | bigint	The number or bigint to be decremented.

Returns

The decremented number or bigint.

Example

type DecrementNumber = Decrement<5>; // 4
type DecrementBigInt = Decrement<10n>; // 9n
type DecrementNegative = Decrement<-3.14>; // -4.14