Type Alias IsInteger<T>

IsInteger: T extends bigint
    ? true
    : T extends number
        ? number extends T
            ? false
            : T extends PositiveInfinity | NegativeInfinity ? false : Not<IsFloat<T>>
        : false

Returns a boolean for whether the given number is an integer, like -5, 1.0, or 100.

Use-case:

If you want to make a conditional branch based on the result of whether a number is an integer or not.

Type Parameters

Example

import type {IsInteger, PositiveInfinity} from 'type-fest';

type A = IsInteger<1>;
//=> true

type B = IsInteger<1.0>;
//=> true

type C = IsInteger<-1>;
//=> true

type D = IsInteger<0b10>;
//=> true

type E = IsInteger<0o10>;
//=> true

type F = IsInteger<0x10>;
//=> true

type G = IsInteger<1.23e+21>;
//=> true

type H = IsInteger<1.5>;
//=> false

type I = IsInteger<PositiveInfinity>;
//=> false

type J = IsInteger<1e-7>;
//=> false

Type Alias IsInteger<T>

Type Parameters

Example

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