Type Alias IsNumber<T, $O>

Example

type R = IsNumber<number> // true
type R = IsNumber<1> // true

type R = IsNumber<never> // false
type R = IsNumber<unknown> // false
type R = IsNumber<string | boolean> // false

type R = IsNumber<string | number> // boolean
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🔢 customize

Filter to ensure T is number or number literals, otherwise returns never.

Example

type R = IsNumber<number, { selection: 'filter' }> // number
type R = IsNumber<1, { selection: 'filter' }> // 1

type R = IsNumber<never, { selection: 'filter' }> // never
type R = IsNumber<unknown, { selection: 'filter' }> // never
type R = IsNumber<string | boolean, { selection: 'filter' }> // never

type R = IsNumber<string | number> // number
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🔢 customize:

Disable distribution of union types.

type R = IsNumber<number | 1> // boolean
type R = IsNumber<number | 1, { distributive: false }> // false
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🔢 customize

Use unique branch identifiers to allow precise processing of the result.

Example

type R = IsNumber<number, $SelectionBranch> // $Then
type R = IsNumber<string, $SelectionBranch> // $Else
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