Re: Why don't large companies use Ada?

[eachus@spectre.mitre.org (Robert I. Eachus)]

In article <D03AL2.5xw@aston.ac.uk> bromlegb@aston.ac.uk (An Amoeba) writes:

 > Why should they bother??

   Hmmm.... Should I bother replying?  Only if I can do so politely,
this post will certain attract its share of flames.

 > Given that most students coming out of college/University will have some
 > experience in programming some type of language Pascal, Modula-2/3, C
 > and possibly BASIC plus any others and also most colleges/Universities
 > provide courses in C, it is totally logical, and more important cost
 > saving to send/train employees on C++ courses, and thus program systems
 > in C++.

   Let me recast this.  Students who have learned Pascal in school
will have little trouble transitioning to Ada, and those who started
out with the second most popular introductory computing language, Ada,
will have even less trouble.  (As I remember the most recent survey
Scheme is third...is that right Mike?)  Those who learned to program
on their own have most likely learned BASIC or C, and should be sent
to school to learn better practices.  Of course, well trained software
engineers can use any reasonable language.

 > i) Cost. If the user has a basic knowledge of C or other
 > programming language then converting to C++ is relatively easy.

   Reminds me of the two part plan for converting lead into gold.
Part one is to mine the lead. Part two is still in the planning
stages.  Seriously, learning OOP is NOT easy, writing C in C++ is
easy.  If you are planning to use C, use C.

 > ii) Ada's complexity. Most new users will quickly come across all
 > Ada's *nice* type checking, or special constructs which require a
 > different syntax to normal.  In other languages these are not
 > required.

   Yes, strong type checking is very nice, and not very complex.
Special constructs?  Are you referring to the language constructs for
task, exceptions, and/or generics?  But these are nice features to
have available, even C++ has adopted two of them, and if you use them
you do need special syntax.  But most Ada programmers never need to
use features from chapters 9, 12 and 13, so I guess most of that
syntax is not normally required in Ada either.  It's just that in Ada,
it is there when you need it.

  > iii) Support. Virtually every computer system in the world has a
  > C++ compiler, and it is being updated continually. Because that is
  > where all the money is.  Not every computer system in the world
  > has Ada on it, plus most will not be powerful enough to run it.
  > Plus the cost of the respective compilers. C++ compilers, are
  > cheaper than Ada ones. On all if not the majority of platforms.

    Actually if you check, there are Ada compilers available for many
more machines than C++ compilers.  (Especially if you count "bare
boards" and embedded processors.)  On the other hand C is probably the
most popular language in terms of number of targets.  There are many
small chips where the only programming languages available are
assembler, C, and perhaps PL/M or Forth.

 > iv) Libraries, Code already written and available experts. C++ has
 > access straight away to all the C code libraries written. Not just
 > a few nice ones, but all C library code ever written, one reason
 > the famous COBOL is still around!  Lots and lots of code has
 > already been written in C++, and also any company can go out and
 > get any number of C++ programmers, or even C ones and train them,
 > whereas there are fewer Ada programmers.

   It is a LOT easier to build a good Ada interface to a C library
than to build a good C++ interface to the same library.  In either
language a mediocre thin binding can be whipped up quickly.

 > v) OS Support. All modern OS have C and C++ support for there
 > libraries. For Ada to access the same stuff as C and C++ someone
 > has to write specfications for the C and C++ code in the OS. It is
 > not supported straight out by OS Vendors.

   Hmmm...  I must use a lot of ancient OS's.  Seriously, POSIX Ada
bindings (a very good thick binding) are available on most Unix
platforms, and I'm in the process of upgrading the Ada 9X bindings
that Pass Travis developed on the Amiga.  I'm not aware of any real
C++ bindings, on the Amiga or elsewhere.  Am I missing something?

 > This is just my .005 pence worth, and feel totally free to totally disagree.
 
   Not even your full two cents' worth?  I predict you will get a
large on your investment.
--

					Robert I. Eachus

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