Type Alias IsFloat<T>

IsFloat: T extends number
    ? `${T}` extends `${number}e${infer E extends "-" | "+"}${number}`
        ? E extends "-" ? true : false
        : `${T}` extends `${number}.${number}` ? true : false
    : false

Returns a boolean for whether the given number is a float, like 1.5 or -1.5.

Use-case:

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

Type Parameters

Example

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

type A = IsFloat<1.5>;
//=> true

type B = IsFloat<-1.5>;
//=> true

type C = IsFloat<1e-7>;
//=> true

type D = IsFloat<1.0>;
//=> false

type E = IsFloat<PositiveInfinity>;
//=> false

type F = IsFloat<1.23e+21>;
//=> false

Type Alias IsFloat<T>

Type Parameters

Example

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