/** Check two `Headers` field name and field value equality.
 *
 * ```ts
 * import { equalsHeaders } from "https://deno.land/x/http_utils@$VERSION/header.ts";
 * import { assertEquals } from "https://deno.land/std@$VERSION/testing/asserts.ts";
 *
 * assertEquals(
 *   equalsHeaders(new Headers({ a: "b" }), new Headers({ a: "b" })),
 *   true,
 * );
 * assertEquals(
 *   equalsHeaders(new Headers({ a: "b" }), new Headers({ c: "d" })),
 *   false,
 * );
 * ```
 *
 * @deprecated Move to [headers-utils](https://github.com/httpland/headers-utils).
 */
export declare function equalsHeaders(left: Headers, right: Headers): boolean;
/** Returns a new {@link Headers} with all entries of the given headers except the ones that have a key(header name or field name) that does not match the given predicate.
 *
 * @example
 * ```ts
 * import { filterKeys } from "https://deno.land/x/http_utils@$VERSION/header.ts";
 * import { assert } from "https://deno.land/std@$VERSION/testing/asserts.ts";
 *
 * const headers = filterKeys(
 *   new Headers({
 *     "date": "<date>",
 *     "content-type": "<content-type>",
 *   }),
 *   (key) => key.startsWith("content"),
 * );
 *
 * assert(headers.has("content-type"));
 * assert(!headers.has("date"));
 * ```
 *
 * @deprecated Move to [headers-utils](https://github.com/httpland/headers-utils).
 */
export declare function filterKeys(headers: Headers, predicate: (key: string) => boolean): Headers;
/** HTTP Message Metadata header fields.
 * @see [RFC 9110, 6.6. Message Metadata](https://www.rfc-editor.org/rfc/rfc9110.html#section-6.6)
 *
 * @example
 * ```ts
 * import { MessageMetadataHeader } from "https://deno.land/x/http_utils@$VERSION/header.ts";
 * import { assertEquals } from "https://deno.land/std@$VERSION/testing/asserts.ts";
 *
 * assertEquals(MessageMetadataHeader.Date, "date");
 * ```
 */
export declare enum MessageMetadataHeader {
    /**
     * @see [RFC 9110, 6.6.1. Date](https://www.rfc-editor.org/rfc/rfc9110.html#section-6.6.1)
     */
    Date = "date",
    /**
     * @see [RFC 9110, 6.6.2. Trailer](https://www.rfc-editor.org/rfc/rfc9110.html#section-6.6.2)
     */
    Trailer = "trailer"
}
/** HTTP Message Forwarding header fields.
 * @see [RFC 9110, 7.6. Message Forwarding](https://www.rfc-editor.org/rfc/rfc9110.html#section-7.6)
 *
 * @example
 * ```ts
 * import { MessageForwardingHeader } from "https://deno.land/x/http_utils@$VERSION/header.ts";
 * import { assertEquals } from "https://deno.land/std@$VERSION/testing/asserts.ts";
 *
 * assertEquals(MessageForwardingHeader.Via, "via");
 * ```
 */
export declare enum MessageForwardingHeader {
    /**
     * @see [RFC 9110, 7.6.1. Connection](https://www.rfc-editor.org/rfc/rfc9110.html#section-7.6.1)
     */
    Connection = "connection",
    /**
     * @see [RFC 9110, 7.6.2. Max-Forwards](https://www.rfc-editor.org/rfc/rfc9110.html#section-7.6.2)
     */
    MaxForwards = "max-forwards",
    /**
     * @see [RFC 9110, 7.6.3. Via](https://www.rfc-editor.org/rfc/rfc9110.html#section-7.6.3)
     */
    Via = "via"
}
/** HTTP representation data and metadata header fields.
 * @see [RFC 9110, 8. Representations](https://www.rfc-editor.org/rfc/rfc9110.html#section-8)
 *
 * @example
 * ```ts
 * import { RepresentationHeader } from "https://deno.land/x/http_utils@$VERSION/header.ts";
 * import { assertEquals } from "https://deno.land/std@$VERSION/testing/asserts.ts";
 *
 * assertEquals(RepresentationHeader.ContentType, "content-type");
 * ```
 */
export declare enum RepresentationHeader {
    /**
     * @see [RFC 9110, 8.3. Content-Type](https://www.rfc-editor.org/rfc/rfc9110.html#section-8.3)
     */
    ContentType = "content-type",
    /**
     * @see [RFC 9110, 8.4. Content-Encoding](https://www.rfc-editor.org/rfc/rfc9110.html#section-8.4)
     */
    ContentEncoding = "content-encoding",
    /**
     * @see [RFC 9110, 8.5. Content-Language](https://www.rfc-editor.org/rfc/rfc9110.html#section-8.5)
     */
    ContentLanguage = "content-language",
    /**
     * @see [RFC 9110, 8.6. Content-Length](https://www.rfc-editor.org/rfc/rfc9110.html#section-8.6)
     */
    ContentLength = "content-length",
    /**
     * @see [RFC 9110, 8.7. Content-Location](https://www.rfc-editor.org/rfc/rfc9110.html#section-8.7)
     */
    ContentLocation = "content-location",
    /**
     * @see [RFC 9110, 8.8.2. Last-Modified](https://www.rfc-editor.org/rfc/rfc9110.html#section-8.8.2)
     */
    LastModified = "last-modified",
    /**
     * @see [RFC 9110, 8.8.3. ETag](https://www.rfc-editor.org/rfc/rfc9110.html#section-8.8.3)
     */
    ETag = "etag"
}
/** HTTP Authentication header fields.
 * @see [RFC 9110, 11. HTTP Authentication](https://www.rfc-editor.org/rfc/rfc9110#section-11)
 */
export declare enum AuthenticationHeader {
    /**
     * @see [RFC 9110, 11.6.1. WWW-Authenticate](https://www.rfc-editor.org/rfc/rfc9110#section-11.6.1)
     */
    WWWAuthenticate = "www-authenticate",
    /**
     * @see [RFC 9110, 11.6.2. Authorization](https://www.rfc-editor.org/rfc/rfc9110#section-11.6.2)
     */
    Authorization = "authorization",
    /**
     * @see [RFC 9110, 11.6.3. Authentication-Info](https://www.rfc-editor.org/rfc/rfc9110#section-11.6.3)
     */
    AuthenticationInfo = "authentication-info",
    /**
     * @see [RFC 9110, 11.7.1. Proxy-Authenticate](https://www.rfc-editor.org/rfc/rfc9110#section-11.7.1)
     */
    ProxyAuthenticate = "proxy-authenticate",
    /**
     * @see [RFC 9110, 11.7.2. Proxy-Authorization](https://www.rfc-editor.org/rfc/rfc9110#section-11.7.2)
     */
    ProxyAuthorization = "proxy-authorization",
    /**
     * @see [RFC 9110, 11.7.3. Proxy-Authentication-Info](https://www.rfc-editor.org/rfc/rfc9110#section-11.7.3)
     */
    ProxyAuthenticationInfo = "proxy-authentication-info"
}
/** HTTP content negotiation header fields.
 * @see [RFC 9110, 12. Content Negotiation](https://www.rfc-editor.org/rfc/rfc9110#section-12)
 *
 * @example
 * ```ts
 * import { ContentNegotiationHeader } from "https://deno.land/x/http_utils@$VERSION/header.ts";
 * import { assertEquals } from "https://deno.land/std@$VERSION/testing/asserts.ts";
 *
 * assertEquals(ContentNegotiationHeader.Accept, "accept");
 * ```
 */
export declare enum ContentNegotiationHeader {
    /**
     * @see [RFC 9110, 12.5.1. Accept](https://www.rfc-editor.org/rfc/rfc9110#section-12.5.1)
     */
    Accept = "accept",
    /**
     * @see [RFC 9110, 12.5.2. Accept-Charset](https://www.rfc-editor.org/rfc/rfc9110#section-12.5.2)
     */
    AcceptCharset = "accept-charset",
    /**
     * @see [RFC 9110, 12.5.3. Accept-Encoding](https://www.rfc-editor.org/rfc/rfc9110#section-12.5.3)
     */
    AcceptEncoding = "accept-encoding",
    /**
     * @see [RFC 9110, 12.5.4. Accept-Language](https://www.rfc-editor.org/rfc/rfc9110#section-12.5.4)
     */
    AcceptLanguage = "accept-language",
    /**
     * @see [RFC 9110, 12.5.5. Vary](https://www.rfc-editor.org/rfc/rfc9110#section-12.5.5)
     */
    Vary = "vary"
}
/** HTTP conditional requests header fields.
 * @see [RFC 9110, 13. Conditional Requests](https://www.rfc-editor.org/rfc/rfc9110#section-13)
 *
 * @example
 * ```ts
 * import { ConditionalHeader } from "https://deno.land/x/http_utils@$VERSION/header.ts";
 * import { assertEquals } from "https://deno.land/std@$VERSION/testing/asserts.ts";
 *
 * assertEquals(ConditionalHeader.IfNoneMatch, "if-none-match");
 * ```
 */
export declare enum ConditionalHeader {
    /**
     * @see [RFC 9110, 13.1.1. If-Match](https://www.rfc-editor.org/rfc/rfc9110#section-13.1.1)
     */
    IfMatch = "if-match",
    /**
     * @see [RFC 9110, 13.1.2. If-None-Match](https://www.rfc-editor.org/rfc/rfc9110#section-13.1.2)
     */
    IfNoneMatch = "if-none-match",
    /**
     * @see [RFC 9110, 13.1.3. If-Modified-Since](https://www.rfc-editor.org/rfc/rfc9110#section-13.1.3)
     */
    IfModifiedSince = "if-modified-since",
    /**
     * @see [RFC 9110, 13.1.4. If-Unmodified-Since](https://www.rfc-editor.org/rfc/rfc9110#section-13.1.4)
     */
    IfUnmodifiedSince = "if-unmodified-since",
    /**
     * @see [RFC 9110, 13.1.5. If-Range](https://www.rfc-editor.org/rfc/rfc9110#section-13.1.5)
     */
    IfRange = "if-range"
}
/** HTTP range requests header fields.
 * @see [RFC 9110, 14. Range Requests](https://www.rfc-editor.org/rfc/rfc9110#section-14)
 *
 * @example
 * ```ts
 * import { RangeHeader } from "https://deno.land/x/http_utils@$VERSION/header.ts";
 * import { assertEquals } from "https://deno.land/std@$VERSION/testing/asserts.ts";
 *
 * assertEquals(RangeHeader.Range, "range");
 * ```
 */
export declare enum RangeHeader {
    /**
     * @see [RFC 9110, 14.2. Range](https://www.rfc-editor.org/rfc/rfc9110#section-14.2)
     */
    Range = "range",
    /**
     * @see [RFC 9110, 14.3. Accept-Ranges](https://www.rfc-editor.org/rfc/rfc9110#section-14.3)
     */
    AcceptRanges = "accept-ranges",
    /**
     * @see [RFC 9110, 14.4. Content-Range](https://www.rfc-editor.org/rfc/rfc9110#section-14.4)
     */
    ContentRange = "content-range"
}
/** HTTP Caching header fields.
 * @see [RFC 9111, HTTP Caching](https://www.rfc-editor.org/rfc/rfc9111)
 *
 * @example
 * ```ts
 * import { CachingHeader } from "https://deno.land/x/http_utils@$VERSION/header.ts";
 * import { assertEquals } from "https://deno.land/std@$VERSION/testing/asserts.ts";
 *
 * assertEquals(CachingHeader.CacheControl, "cache-control");
 * ```
 */
export declare enum CachingHeader {
    /**
     * @see [RFC 9111, 5.1. Age](https://www.rfc-editor.org/rfc/rfc9111#section-5.1)
     */
    Age = "age",
    /**
     * @see [RFC 9111, 5.2. Cache-Control](https://www.rfc-editor.org/rfc/rfc9111#section-5.2)
     */
    CacheControl = "cache-control",
    /**
     * @see [RFC 9111, 5.3. Expires](https://www.rfc-editor.org/rfc/rfc9111#section-5.3)
     */
    Expires = "expires"
}
/** Whether the input is {@link MessageMetadataHeader} or not.
 *
 * @example
 * ```ts
 * import { isMessageMetadataHeader } from "https://deno.land/x/http_utils@$VERSION/header.ts";
 * import { assert } from "https://deno.land/std@$VERSION/testing/asserts.ts";
 *
 * assert(isMessageMetadataHeader("date"));
 * assert(!isMessageMetadataHeader("<others>"));
 * ```
 */
export declare function isMessageMetadataHeader(input: string): input is `${MessageMetadataHeader}`;
/** Whether the input is {@link MessageForwardingHeader} or not.
 *
 * @example
 * ```ts
 * import { isMessageForwardingHeader } from "https://deno.land/x/http_utils@$VERSION/header.ts";
 * import { assert } from "https://deno.land/std@$VERSION/testing/asserts.ts";
 *
 * assert(isMessageForwardingHeader("connection"));
 * assert(!isMessageForwardingHeader("<others>"));
 * ```
 */
export declare function isMessageForwardingHeader(input: string): input is `${MessageForwardingHeader}`;
/** Whether the input is {@link RepresentationHeader} or not.
 *
 * @example
 * ```ts
 * import { isRepresentationHeader } from "https://deno.land/x/http_utils@$VERSION/header.ts";
 * import { assert } from "https://deno.land/std@$VERSION/testing/asserts.ts";
 *
 * assert(isRepresentationHeader("content-type"));
 * assert(!isRepresentationHeader("<others>"));
 * ```
 */
export declare function isRepresentationHeader(input: string): input is `${RepresentationHeader}`;
/** Whether the input is {@link AuthenticationHeader} or not.
 *
 * @example
 * ```ts
 * import { isAuthenticationHeader } from "https://deno.land/x/http_utils@$VERSION/header.ts";
 * import { assert } from "https://deno.land/std@$VERSION/testing/asserts.ts";
 *
 * assert(isAuthenticationHeader("authorization"));
 * assert(!isAuthenticationHeader("<others>"));
 * ```
 */
export declare function isAuthenticationHeader(input: string): input is `${AuthenticationHeader}`;
/** Whether the input is {@link ContentNegotiationHeader} or not.
 *
 * @example
 * ```ts
 * import { isContentNegotiationHeader } from "https://deno.land/x/http_utils@$VERSION/header.ts";
 * import { assert } from "https://deno.land/std@$VERSION/testing/asserts.ts";
 *
 * assert(isContentNegotiationHeader("accept"));
 * assert(!isContentNegotiationHeader("<others>"));
 * ```
 */
export declare function isContentNegotiationHeader(input: string): input is `${ContentNegotiationHeader}`;
/** Whether the input is {@link ConditionalHeader} or not.
 *
 * @example
 * ```ts
 * import { isConditionalHeader } from "https://deno.land/x/http_utils@$VERSION/header.ts";
 * import { assert } from "https://deno.land/std@$VERSION/testing/asserts.ts";
 *
 * assert(isConditionalHeader("if-match"));
 * assert(!isConditionalHeader("<others>"));
 * ```
 */
export declare function isConditionalHeader(input: string): input is `${ConditionalHeader}`;
/** Whether the input is {@link RangeHeader} or not.
 *
 * @example
 * ```ts
 * import { isRangeHeader } from "https://deno.land/x/http_utils@$VERSION/header.ts";
 * import { assert } from "https://deno.land/std@$VERSION/testing/asserts.ts";
 *
 * assert(isRangeHeader("range"));
 * assert(!isRangeHeader("<others>"));
 * ```
 */
export declare function isRangeHeader(input: string): input is `${RangeHeader}`;
/** Whether the input is {@link CachingHeader} or not.
 *
 * @example
 * ```ts
 * import { isCachingHeader } from "https://deno.land/x/http_utils@$VERSION/header.ts";
 * import { assert } from "https://deno.land/std@$VERSION/testing/asserts.ts";
 *
 * assert(isCachingHeader("age"));
 * assert(!isCachingHeader("<others>"));
 * ```
 */
export declare function isCachingHeader(input: string): input is `${CachingHeader}`;