Type alias IsVoid<T, $O>

🎭 predicate

Validate if T is void.

Example

type R = IsVoid<void> // true

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

type R = IsVoid<string | void> // boolean
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🔢 customize

Filter to ensure T is void, otherwise returns never.

Example

type R = IsVoid<void, { selection: 'filter' }> // void

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

type R = IsVoid<string | void> // void
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🔢 customize:

Disable distribution of union types.

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

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

Example

type R = IsVoid<void, $SelectionBranch> // $Then
type R = IsVoid<string, $SelectionBranch> // $Else
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