Re: forth/fifth generation languages?

[cis.ohio-state.edu!math.ohio-state.edu!darwin.sura.net!dtix.dt.navy.mil!c]

I agree with previous postings about the differences between 1st,
2nd, 3rd, and 4th generation languages.  The statements
accurately represent the conventional interpretation of the
progression. 

I'd like to share an observation that there were correlated
correlated changes in what a programmer was required to know and
how programmers worked with other people.

The 1st generation programmer knew the hardware wiring diagram as
well as every detail of the code.  There were no libraries to
speak of and the applications - while revolutionary - were small
are exceedingly rare.  

The 2nd generation programmer worked with an abstract model of
the hardware.  2nd generation programmers also had a library
system so that they could employ many functions without coding
each one.  This freed them to make larger applications that were
numerous enough to appear in many application domains.

The 3rd generation marked a major change in programming because
fairly ordinary people could master both an application domain
and enough programming skills to write code for it.  That wasn't
the intention, but some line was crossed and the nature of
programming work changed.  Now the sky seemed the only limit.  If
you found a team of domain experts and a team of programmers who
understood domain jargon, you could develop anything, it seemed,
cost not withstanding!

The 4th generation language marks a paradigm shift.  A fourth
generation language is usable by an application domain expert who
is not a programmer at all.  In this paradigm, the programmer is
no longer needed to translate requirements and equations into
software.  Costs go down, and delivery times are shortened
relative to the 3rd generation.

Whatever happens to computer languages, the way people work
together will continue to evolve and that evolution may be more
important than language features.  

Two short, related points:

1) There doesn't have to be a syntax difference between 3rd and
4th generation.  During the STARS Foundations era, I showed how
to do megaprogramming - the synthesis of very large programs from
correspondingly large components - using Ada as a 4GL.  Under the
same program, Lockheed demonstrated that Ada is competent to
express statements usually stated in SQL.  If nobody has a 4GL
for your application - consider shifting your paradigm and
sticking with the established languages: Ada and C++.

2) There are still hard problems associated with 4GLs:
  * 4GLs don't cover all the application domains
	* 4GLs can't cross domains to meet all the requirements of
	  a large system. 
  * 4GLs cost a bundle to develop, and they are usually 
	  nonstandard and proprietary.   

-----------------------------------------
Paul L. Baker     pbaker@cta.com 
CTA Inc.
6116 Executive Blvd. Suite 800
Rockville, MD 20852
(301) 816-1242