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includes

includes() function​

Checks if the specified value is equal. (contains)

Signature: 
declare function includes<T>(value: unknown, iterable: Iterable<T>): boolean;

declare function includes<T extends readonly []>(value: unknown, iterable: T): false;

declare function includes<T, U extends T>(value: T, iterable: Iterable<U>): value is U;

declare function includes<T>(value: unknown, iterable: AsyncIterable<T>): Promise<boolean>;

declare function includes<T extends Iterable<unknown> | AsyncIterable<unknown>>(value: unknown): (iterable: T) => ReturnValueType<T, boolean>;

Example​

includes('c', 'abcd'); // true
includes('e', 'abcd'); // false
includes(3, [1,2,3,4]); // true
includes(5, [1,2,3,4]); // false

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