type Headers<T> = Record<string, T>;
/**
 * Given a headers object retrieve a specific header out of it via a case-insensitive key.
 */
export declare const getHeaderName: <T>(headers: Headers<T>, name: string) => string | undefined;
/**
 * Given a headers object retrieve the contents of a header out of it via a case-insensitive key.
 */
export declare const getHeader: <T>(headers: Headers<T>, name: string) => T | undefined;
/**
 * Determine if a given case-insensitive header exists within a header object.
 */
export declare const hasHeader: <T>(headers: Headers<T>, name: string) => boolean;
/**
 * Determines if a given mimetype is JSON, or a variant of such.
 */
export declare const isMimeTypeJSON: (mimeType: string) => mimeType is `${string}application/json${string}` | `${string}application/x-json${string}` | `${string}text/json${string}` | `${string}text/x-json${string}` | `${string}+json${string}`;
export {};