IfNumberInteger.md

typelab / conditions / IfNumberInteger

type IfNumberInteger<T, Then, Else> = _IfNotAnyOrNever<T, T extends number ? number extends T ? Else : `${T}` extends `${infer _ extends number}.${infer __ extends number}` ? Else : Then : Else, Else>;

Resolves to Then if the type T is integer number literal, otherwise resolves to Else.

Type Parameters

Type Parameter	Default type	Description
T	‐	The type to be checked.
Then	‐	The type to return if T is integer number literal.
Else	never	The type to return if T is not integer number literal. Defaults to never.

Returns

Then if T is integer number literal, Else otherwise.

Example

type Yes = IfNumberInteger<11, 'yes', 'no'>; // 'yes'
type No = IfNumberInteger<11.1, 'yes', 'no'>; // 'no'
type YesOrNo = IfNumberInteger<11 | 11.1, 'yes', 'no'>; // 'yes' | 'no'