Type alias IsNumberLiteral<T, $O>

🎭 predicate

Validate if T is number literals.

Example

type R = IsNumberLiteral<number> // false
type R = IsNumberLiteral<1> // true

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

type R = IsNumberLiteral<string | 1> // boolean
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🔢 customize

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

Example

type R = IsNumberLiteral<number, { selection: 'filter' }> // never
type R = IsNumberLiteral<1, { selection: 'filter' }> // 1

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

type R = IsNumberLiteral<string | 1> // 1
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🔢 customize:

Disable distribution of union types.

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

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

Example

type R = IsNumberLiteral<1, $SelectionBranch> // $Then
type R = IsNumberLiteral<string, $SelectionBranch> // $Else
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