ConTEXt - Pragma ADE

Introduction
This is the first issue of ConT E Xt up--to--date. I will use this series of documents to introduce new
features, provide suggestions, mention tricks, and write down whatever else comes up.
In this first, rather large issue, I will introduce the extended cross reference mechanism, fill--in fields
and JavaScript support. Although the latter two are still sort of β, the more final release will offer
at least the functionality presented here. I will also show some applications of fields combined with
JavaScript.
New is the support of comment (text annotations in pdf terminology). Although already present
some time, I will also discuss page transitions. Due to the fact that pdfT E X now supports pdf
inclusion, I will introduce some new features of the figure inclusion mechanism, especially automatic
type recognition.
Chained references
About half a year ago (end 1997/begin 1998) I reimplemented part of the reference macros. The
reference mechanism not only deals with the more traditional cross references, but also takes care of
hyperefences, navigational means, launching applications, running JavaScript, etc. By integrating
these features in one mechanism, we limit the number of commands needed for hyperreferences,
menus and buttons. Like before, we have the normal cross references (here I only demonstrate
\goto):
\goto[reference]
\goto[outer reference::]
\goto[outer reference::inner reference]
The inner reference is either a user defined one, or a system provided reference, like previouspage
to go to the next page, forward to cycle, nextcontents for the next level table of contents in a
linked list of such tables, etc. By the way, some new keywords are backward and forward, two
cycling alternatives for previous and next, that jump from last page to the first one and vice versa.
The outer reference, being a file or url, is defined at the document level and is accessed by the ::.
When possible one should use logical names and define such files and url’s at the outer document
level using the appropriate definition commands.
A special class of references are the viewer control ones, like CloseDocument or PreviousJump.
They can be recognized by their capitals.
So far, nothing is new but after half a year of experimenting, I decided to make some of these
extensions permanent:
\goto[action{arguments}]
\goto[operation(arguments)]
\goto[operation(action{arguments})]
1 up--to--date 1998/1 stripped screen version