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- Path: sparky!uunet!stanford.edu!agate!ucbvax!NTSC-RD.NAVY.MIL!byrley
- From: byrley@NTSC-RD.NAVY.MIL ("Paul Byrley")
- Newsgroups: comp.lang.ada
- Subject: Play 20K expressions again, Sam
- Message-ID: <9208281536.AA01868@ajpo.sei.cmu.edu>
- Date: 28 Aug 92 16:29:00 GMT
- Sender: usenet@ucbvax.BERKELEY.EDU
- Organization: The Internet
- Lines: 52
-
- I was willing to be prejudiced again against "those academics" when
- I first read about the supposed bug in a compiler that balked at 20k
- expressions. After reading Sam Harbaugh's good natured
- commentary, I rethought my position and decided to just comment.
-
- About 1985, I asked the net at SIMTEL20 what to do about
- contractually limiting the size of Ada packages. We had been using
- FORTRAN and MIL-STD-1679 or 1644 where the limit was 200 LOC
- for a sub-program (1679 and 1644 predated Ada by 5 to 10 years).
- I thought 200 LOC was excessive for good life cycle support
- (assuming 50% comments and 64 lines per line printer page you got
- 6 pages of code plus a page or two of declaratives). We had just
- started talking about the Hrair limit then, thanks to Grady Booch (and,
- I think, some rabbit in Watership Downs) and six pages of listings was
- too much for my brain to encompass. I felt sure, however, that the
- 200 LOC limit we used for FORTRAN subroutines wouldn't translate
- into a valid Ada limit. Anyhow, when I asked the net, I got back
- about eight comments, all saying "no LOC limits for Ada packages".
- I believe that Grady Booch and Ed Berard were among the
- commenters and that was support enough for me.
-
- Since then, our agency has used the no LOC limit approach on
- probably 50 procurements for real time training systems, ranging in
- size from 5000 LOC to 800K LOC of Ada. I think only one vendor
- has violated what, as near as I can tell, is industry agreement on good
- practice on package size. Most packages seem to be from 100 to
- 500 LOC, and almost never over 1000 LOC. The one "violator of
- good practice" insisted on delivering a 10K LOC package. It worked,
- but is going to be more expensive for all us taxpayers to support for
- the next 10 to 15 years.
-
- My opinion is that if a person is hanging together large amounts of
- code and will support it himself forever (promises not to quit or die
- before his employer ceases to need the software), then 20K
- expressions is ok. (Does one expression = one LOC or are we talking
- one expression = LOC/4 to LOC/8?) If a taxpayer (even a federal
- research grant comes from taxpayers) is going to have to pay extra for
- the indulgence of a 20K expression programmer, then I thank Verdix
- for their choice. Actually I wish it were lower. I remember, years ago,
- learning that the reason my latest FORTRAN "gem" was not compiling
- was that I had overrun the compiler tables- that program was about
- 1000 LOC and I was briefly indignant also. Yeah Sam, that was half
- a box of cards, red ones and blue ones and even green ones, with a
- diagonal magic marker across the top so you could maybe recover
- when someone dropped them.
-
- Regards to all, even the long package advocates.
-
- Paul Byrley
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