import type { DocumentNode } from '@apollo/client/core';
/**
 * Validates a graphql document node.
 *
 * ```haskell
 * isValidGql :: DocumentNode a => a -> Bool
 * ```
 * @param doc Maybe a DocumentNode
 * @return Whether the argument is a DocumentNode
 */
export declare function isValidGql(doc: any): doc is DocumentNode;