The First Lost Attribute of A: TYPE

By mid-1993 when this attribute had been renamed "REL" (and a corresponding "REV" attribute also introduced to provide an inverse relationship description), the list vaguely proposed in 1992 had firmed up to some rather interesting list of alternatives. Some of them would serve only as mere descriptive terms, perhaps to be used by search engines to know what it they are looking at, or if a link button were to be provided in the frame of the browser (as it was on Mosaic) there could be a small graphic to provide the user with some hint of what the file is.

But several of the possible values for TYPE also had something much more interesting one great idea abandonded almost immediately and never restored to regular HTML, and that is the embedded or "present" text. If one were to set "TYPE=PRESENT" the file pointed to would be also retrieved and inserted into the location in place of a visible "<A>" tag. Quickly eliminated from HTML, this functionality would soon resurface in the Server Side Includes, which achieve the same effect, but from the server side instead of the client side. There is a good reason why this sort of functionality was not added to the HTML language, and that is the problem of what to do if a file calls another file, which in turn calls the first file, which calls the second calling the first yet again, and so on. As the number of kinds of HTTP server software packages is quite small, it is a trivial matter to see to it that every server is protected from that kind of mistake, either by limiting how many levels deep one can go, or else by keeping track of file names and returning an error message instead of the contents of a file already called higher up. But with all the possible browsers coming along and so many more yet to come, how easy it would be for one or more to omit this sort of programming protection, or supply it inadequately, such that a malicious web designer could tie up a server indefinately or even crash it.

A similar value, "TYPE=EMBED," was originally thought to be similar to this but later on it hardened into a kind of scripting action, where you would click on it, and then it would fetch the contents of its destination and insert it. This kind of functionality would avoid the danger of "PRESENT" in that the user must manually click on each file to cause it to be read in, thus limiting how deep it could go. This kind of functionality might at best only be approximated with scripting languages, and one really has to wonder how "Guide" implemented it.

In the 1993 version (using "REL" instead of "TYPE"), the following list of values had been proposed:

• USEINDEX - the file pointed to should be an indexed file (using "<ISINDEX>"), merely informational
• USEGLOSSARY - a term could be clicked on to go to its definition in a glossary file, should prevent the link from looking like a link
• ANNOTATION - pointer to some small file with the equivalent to a sort of margin note, sort of replaced with the "TITLE" attribute which can put a small indicator up when the mouse is rolled over it, or like a Javascript popup window which can put an additional explanation on the screen when requested, or the "LONGDESC" attribute to some other tags which can provide a description made available upon request, but as intended originally, this was merely informational
• REPLY - pointer to an equivalent document, not subordinated to or by the source document, merely informational
• EMBED - a click on this link can bring up text from a file and insert it inline in the document, could be useful if (for example) you want to check a stock price and click on it whenever you want to read the latest price
• PRECEDES - later changed to "PREV" (and corresponding "NEXT" introduced), merely informational
• SUBDOCUMENT - from an index or contents or main page, this denotes a destination which is hierarchically "under" the present page, merely informational
• PRESENT - user agent (client) automatically retrieves the destination file and inserts it text inline
• SEARCH - call up a search engine (this would appear to obviate the need for having either a "NAME" or "HREF" attribute, since presumably some standard search engine would be sought instead of some page, even one with a search engine
• SUPESEDES - the destination is merely some previous version of the present page "superseded" by the current page, merely informational
• HISTORY - the destination file is a document history, merely informational
• INCLUDES - hint that one file includes information from another, merely informational
• MADE - author of present file made destination file, merely informational
• INTERESTED - destination file is list of interested parties to inform if the page is updated, merely informational in browser, but web page editing software could use this file to know who to inform (list of email addresses) whenever the file is updated

text

Here are some other possibilities to experiment with. If you can track down a working "Guide" browser, it might do something interesting with one or more of them (but again replacing "<" with "[" and ">" with "]" for validity):

which results in:

text

In HTML 4 the "TYPE" attribute would be reintroduced, but with a different function and purpose altogether.

Recommended Implementation

Upgrades and Downgrades

• None - This attribute existed as little more than a speculative attribute, a place holder in the language, at the very beginning of the concept. When finally implemented, it was given a different name ("REL").

• "REL" and "REV" for "TYPE" - If the intent is purely informational, some of the possible attribute values have their conterparts in the following partial list of "REL" attribute values: Start, Next, Prev, Contents, Index , Glossary, Copyright, Chapter, Section, Subsection, Appendix, Help, Bookmark. In addition, two particularly useful "REL" values, Stylesheet and Alternate (for Alternate Stylesheet) would later emerge in HTML 4 with the introduction of style sheets, and provide "<LINK>" (in particular) with a new function. On "<A>" however, the "REL" attribute (like "REV") has no effect.
• Incuding text with Server Side Includes - Server Side includes are one way to perform the function of the "PRESENT" function; originally "EMBED" may have been thought to function this way.

The Server Side Include demonstration file "atype1.shtml" is HTML 2.0 Level 1 compliant.

The Raw Text demonstration file "fatima.txt" is ascii text, so HTML validation does not apply to it. __________________________________________________________________

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