THeaders

type THeaders = set of (

  hhUnknown,

  hhAccept,

  hhAcceptCharset,

  hhAcceptEncoding,

  hhAcceptLanguage,

  hhAcceptRanges,

  hhAge,

  hhAllow,

  hhAuthorization,

  hhCacheControl,

  hhConnection,

  hhContentEncoding,

  hhContentLanguage,

  hhContentLength,

  hhContentLocation,

  hhContentMD5,

  hhContentRange,

  hhContentType,

  hhDate,

  hhETag,

  hhExpires,

  hhExpect,

  hhFrom,

  hhHost,

  hhIfMatch,

  hhIfModifiedSince,

  hhIfNoneMatch,

  hhIfRange,

  hhIfUnModifiedSince,

  hhLastModified,

  hhLocation,

  hhMaxForwards,

  hhPragma,

  hhProxyAuthenticate,

  hhProxyAuthorization,

  hhRange,

  hhReferer,

  hhRetryAfter,

  hhServer,

  hhTE,

  hhTrailer,

  hhTransferEncoding,

  hhUpgrade,

  hhUserAgent,

  hhVary,

  hhVia,

  hhWarning,

  hhWWWAuthenticate

);