/**
 * Returns the version carried by an `Accept` header for media type versioning,
 * e.g. `2` for `application/json;v=2` with the `v=` key.
 *
 * The version parameter may follow other parameters and may belong to any
 * media range of a list (`text/html, application/json;v=2`); the first match
 * wins. Returns `undefined` when no parameter starts with the key.
 *
 * Duplicated in each platform package so that a platform package never
 * depends on a newer `@nestjs/core` than the one installed.
 */
export declare function getMediaTypeVersion(acceptHeader: string | string[] | undefined, key: string): string | undefined;