kinnersley@kuhub.cc.ukans.edu (Bill Kinnersley) (12/19/90)
In article <1990Dec13.084916.15659@ariel.unm.edu>, prentice@hydra.unm.edu (Colston Chandler PHYSICS) writes:
:
: Whatever did happen to Algol? You see alot of the old ACM algorithms
: programmed in it and it looked rather interesting. I can remember
: seeing satellite ephemeris programs written in it 20 years ago, but you never
: hear of it anymore.
:
Algol suffered some unfortunate adverse publicity when Pascal came out,
and was forced underground. However it has been kept alive all these
years by a small but dedicated network of users. Sorry I can't tell you
who they are--in the spirit of data hiding, each of us only knows the
names of two others.
Under our care Algol has continued to grow. The number of reserved
words is now 10,523, and the syntax diagrams are three-dimensional.
The latest version is Algol-88, but an object-oriented derivative
called Algol:= is under active development.
To appreciate fully the features of Algol-88 you must be aware of some
things about the old Algol-68. Algol-68 was written in two separate
styles, one for publication and one for actual programming. With the
advent of desktop publishing this is no longer necessary, and Algol-88
programs are now entered directly in Times-Roman, with reserved words
in Helvetica Bold.
Data types supported are integer, real, complex, quaternion, character,
string, sentence, paragraph, stream, list, record, tape and compact disk.
Among the features of Algol-68 criticized as too complex was the
loop construct, for-from-by-to-while-do-od. In fact it had not
reached its full potential, and in Algol-88 has the more general form
for-from-by-to-with-while-using-do-od-until. The basic conditional
construct has been expanded to if-then-elif-unless-yet-ontheotherhand-fi.
In the interest of simplicity we have abolished the goto.
Algol-88 has extensive support for multiprogramming. Processes may be
lightweight, heavyweight, bantamweight or overweight, and they communicate
via semaphores, monitors, message queues, interrupts and exceptions,
not to mention shared memory and rendezvouses. There is something for
everyone in Algol-88.