<
language> (VPL) Any
programming language that allows the user
to specify a
program in a two-(or more)-dimensionsional way.
Conventional textual languages are not considered
two-dimensional since the
compiler or
interpreter
processes them as one-dimensional streams of characters. A
VPL allows
programming with
visual expressions - spatial
arrangements of textual and graphical symbols.
VPLs may be further classified, according to the type and
extent of
visual expression used, into
icon-based languages,
form-based languages and
diagram languages. {
Visual
programming environments} provide graphical or iconic elements
which can be manipulated by the user in an interactive way
according to some specific spatial grammar for
program
construction.
A visually transformed
language is a non-
visual language with
a superimposed
visual representation. Naturally
visual
languages have an inherent
visual expression for which there
is no obvious textual equivalent.
Visual Basic,
Visual C++ and the entire
Microsoft Visual
family are not, despite their names,
visual programming
languages. They are textual languages which use a graphical
GUI builder to make
programming interfaces easier. The user
interface portion of the
programming environment is
visual,
the languages are not. Because of the confusion caused by the
multiple meanings of the term "
visual programming", Fred
Lakin has proposed the term "executable graphics" as an
alternative to VPL.
Some examples of
visual programming languages are
Prograph,
Pict,
Tinkertoy,
Fabrik,
CODE 2.0 and
Hyperpascal.
http://cogs.susx.ac.uk/users/ianr/vpl.html.
http://cuiwww.unige.ch/eao/www/readme.html.
Usenet newsgroup:
news:comp.lang.visual (NOT for {
Visual
Basic} or
Visual C++).
(1995-02-10)