drag and drop
A common method for manipulating files (and sometimes text) under a graphical
user interface or WIMP environment. The user moves the pointer over an icon
representing a file and presses a mouse button. He holds the button down while
moving the pointer (dragging the file) to another place, usually a directory
viewer or an icon for some application program, and then releases the button
(dropping the file). The meaning of this action can often be modified by holding
certain keys on the keyboard at the same time.
Some systems also use this technique for objects other than files, e.g. portions
of text in a word processor.
The biggest problem with drag and drop is does it mean "copy" or "move"? The
answer to this question is not intuitively evident, and there is no consensus
for which is the right answer. The same vendor even makes it move in some cases
and copy in others. Not being sure whether an operation is copy or move will
cause you to check very often, perhaps every time if you need to be certain.
Mistakes can be costly. People make mistakes all the time with drag and drop.
Human computer interaction studies show a higher failure rate for such
operations, but also a higher "forgiveness rate" (users think "silly me") than
failures with commands (users think "stupid machine"). Overall, drag and drop
took some 40 times longer to do than single-key commands.
[Erik Naggum <email@example.com>]
DQDB « draco « Draft Once ReUse Many « drag and
» drag-n-drop » DRAGON » dragon
<spelling> Stupid spelling of drag and drop.
draco « Draft Once ReUse Many « drag and drop «
drag-n-drop » DRAGON » dragon » Dragon Book
1. An Esprit project aimed at providing effective support to reuse in real-time
distributed Ada application programs.
2. An implementation language used by BTI Computer Systems.
E-mail: Pat Helland <firstname.lastname@example.org>.
Draft Once ReUse Many « drag and drop « drag-n-drop
DRAGON » dragon » Dragon Book » DRAGOON
[MIT] A program similar to a daemon, except that it is not invoked at all, but
is instead used by the system to perform various secondary tasks. A typical
example would be an accounting program, which keeps track of who is logged in,
accumulates load-average statistics, etc. Under ITS, many terminals displayed a
list of people logged in, where they were, what they were running, etc., along
with some random picture (such as a unicorn, Snoopy or the Enterprise), which
was generated by the "name dragon". Use is rare outside MIT, under Unix and most
other operating systems this would be called a "background demon" or daemon. The
best-known Unix example of a dragon is cron. At SAIL, they called this sort of
thing a "phantom".
drag and drop « drag-n-drop « DRAGON « dragon
» Dragon Book » DRAGOON » drain
<publication> The classic text "Compilers: Principles, Techniques and
Tools", by Alfred V. Aho, Ravi Sethi, and Jeffrey D. Ullman (Addison-Wesley
1986; ISBN 0-201-10088-6). So called because of the cover design featuring a
dragon labelled "complexity of compiler design" and a knight bearing the lance
"LALR parser generator" among his other trappings. This one is more specifically
known as the "Red Dragon Book" (1986); an earlier edition, sans Sethi and titled
"Principles Of Compiler Design" (Alfred V. Aho and Jeffrey D. Ullman;
Addison-Wesley, 1977; ISBN 0-201-00022-9), was the "Green Dragon Book" (1977).
(Also "New Dragon Book", "Old Dragon Book".) The horsed knight and the Green
Dragon were warily eying each other at a distance; now the knight is typing
(wearing gauntlets!) at a terminal showing a video-game representation of the
Red Dragon's head while the rest of the beast extends back in normal space.
See also book titles.
drag-n-drop « DRAGON « dragon « Dragon Book »
DRAGOON » drain » DRAM
<language> A distributed, concurrent, object-oriented Ada-based language
developed in the Esprit DRAGON project by Colin Atkinson at Imperial College in
1989 (Now at University of Houston, Clear Lake). DRAGOON supports
object-oriented programming for embeddable systems and is presently implemented
as an Ada preprocessor.
["Object-Oriented Reuse, Concurrency and Distribution: An Ada-Based Approach",
C. Atkinson, A-W 1991, ISBN 0-2015-6-5277].
DRAGON « dragon « Dragon Book « DRAGOON »
drain » DRAM » DRAM refresh