Type alias IsNotNever<T, $O>

🎭 predicate

Validate if T not never.

Example

type R = IsNotNever<1> // true

type R = IsNotNever<never> // false
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🔢 customize

Filter to ensure T is not never, otherwise returns $Never.

Filter normally returns never in the $else clause. But since we are checking for never here, we have to return $Never instead.

Example

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

type R = IsNotNever<never, { selection: 'filter' }> // $Never
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🔢 customize

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

Example

type R = IsNotNever<never, $SelectionBranch> // $Else
type R = IsNotNever<1, $SelectionBranch> // $Then
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