Type Alias IsTemplateLiteral<T, $O>

Example

type R = IsTemplateLiteral<string> // false
type R = IsTemplateLiteral<'foo'> // false
type R = IsTemplateLiteral<`a${number}`> // true

type R = IsTemplateLiteral<`a${number}` | `${bigint}c`> // true

type R = IsTemplateLiteral<never> // false
type R = IsTemplateLiteral<unknown> // false
type R = IsTemplateLiteral<`${number}` | boolean> // boolean
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🔢 customize

Filter to ensure T is a template literal(s), otherwise returns never.

Example

type R = IsTemplateLiteral<`${number}`, { selection: 'filter' }> // `${number}`
type R = IsTemplateLiteral<'a', { selection: 'filter' }> // never
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🔢 customize:

Disable distribution of union types.

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

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

Example

type R = IsTemplateLiteral<`${number}`, $IsTemplateLiteral.$Branch> // $Then
type R = IsTemplateLiteral<bigint, $IsString.$Branch> // $Else
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