From: sampson@nosc.mil (Charles H. Sampson)
Subject: Re: "Subtract C, add Ada"
Date: Wed, 1 Feb 1995 16:45:13 GMT
Date: 1995-02-01T16:45:13+00:00 [thread overview]
Message-ID: <1995Feb1.164513.23467@nosc.mil> (raw)
In-Reply-To: 3gl06i$s03@miranda.gmrc.gecm.com
In article <3gl06i$s03@miranda.gmrc.gecm.com>,
R.A.L Williams <bill@valiant> wrote:
>In article <1995Jan23.154631.6702@sei.cmu.edu> you(?) wrote:
>:
>: Again, I don't see it. The Ada code makes it clear that *corresponding*
>: elements of the array Q are being copied into P - though, of course,
>: a real Ada programmer (TM) would have written just P := Q. The C code
>: doesn't make that clear - you're going to have to ferret out the
>: initialisations of p and q to determine that. And if you worry about
>: the correctness of the copy - for instance, whether P and Q are the
>: same size - that's surely going to be a lot easier to establish in Ada.
>
>Again, a simplified example to illustrate a principle. The point is that
>the less I have to move my eyes, or flip over pages, when reading/reviewing
^^^ ^^^^ ^ ^^^^ ^^ ^^^^ ^^ ^^^^ ^^ ^^^^ ^^^^ ^^^^^
>code, the more likely I am to understand it and find any bugs. You're
>quite right, P := Q is an event more compact representation and I approve
>(the Bill Williams official statement of approval!).
The marked phrases are what many of us Ada fans are talking about when
we use the word _readability_. P := Q unambiguously shows that the value of
Q is being assigned to P. To repeat you's statement, *p++ = *q++ simply
says that whatever q was pointing to gets copied to whatever p is pointing
to, after which both are modified to point to the "next" thing. Depending
on the complexity of the code, it can take a tremendous amount of ferreting
about, moving eyes and flipping pages, to discover what p and q are pointing
to.
Charlie
next prev parent reply other threads:[~1995-02-01 16:45 UTC|newest]
Thread overview: 85+ messages / expand[flat|nested] mbox.gz Atom feed top
1995-01-31 9:34 "Subtract C, add Ada" R.A.L Williams
1995-02-01 16:45 ` Charles H. Sampson [this message]
-- strict thread matches above, loose matches on Subject: below --
1995-02-10 13:49 R.A.L Williams
[not found] <3gsr0e$oin@miranda.gmrc.gecm.com>
1995-02-07 16:58 ` Mark S. Hathaway
1995-02-08 7:39 ` Travis C. Porco
1995-02-08 16:07 ` Fred J. McCall
1995-02-08 21:30 ` Garlington KE
1995-01-23 8:49 R.A.L Williams
1995-01-25 23:18 ` Charles H. Sampson
1995-01-20 10:20 R.A.L Williams
1995-01-20 13:22 ` Renaud HEBERT
1995-01-24 3:35 ` David Moore
1995-01-25 5:38 ` Robert Dewar
1995-01-28 16:35 ` Jules
1995-01-29 8:06 ` Matt Kennel
1995-01-30 5:31 ` Michael Feldman
1995-01-31 22:22 ` David O'Brien
1995-01-24 20:23 ` N. Mellor
1995-01-25 8:50 ` Robb Nebbe
1995-01-25 14:19 ` John Volan
1995-01-26 5:07 ` Samuel Mize
1995-01-26 18:51 ` Mark A Biggar
1995-01-21 15:18 ` Robert Dewar
1995-01-21 21:03 ` David O'Brien
1995-01-23 3:09 ` Jay Martin
1995-01-23 12:50 ` Andrew McConnell
1995-01-24 0:54 ` Matt Kennel
1995-01-25 17:03 ` Norman H. Cohen
1995-01-26 1:13 ` Dr. Richard Botting
1995-01-26 14:32 ` Anders Juul Munch
1995-01-24 0:17 ` Bob Kitzberger
1995-01-23 20:46 ` Robert Firth
1995-01-24 14:25 ` Samuel Mize
1995-01-25 7:27 ` David O'Brien
1995-01-25 12:14 ` Robert A Duff
1995-01-25 5:57 ` David O'Brien
[not found] ` <3g9rf0$71k@Starbase.NeoSoft.COM>
1995-01-28 21:08 ` David O'Brien
1995-01-31 18:07 ` Samuel Mize
1995-02-01 10:23 ` Samuel Mize
1995-01-30 0:24 ` Mark S. Hathaway
1995-01-31 3:30 ` Jay Martin
1995-02-01 13:25 ` Jesper Kaagaard
1995-01-20 9:33 R.A.L Williams
[not found] <3fgphd$sc3@rational.rational.com>
1995-01-20 5:51 ` RonaldS60
1995-02-07 13:55 ` Robert C. Soong
[not found] <3fdcoi$chn@miranda.gmrc.gecm.com>
1995-01-20 5:01 ` Samuel Mize
1995-01-20 22:07 ` Garlington KE
1995-01-24 5:02 ` R_Tim_Coslet
[not found] <3etund$hnr@miranda.gmrc.gecm.com>
1995-01-12 9:56 ` Erik Svensson
1995-01-12 14:44 ` Norman H. Cohen
1995-01-13 1:51 ` David O'Brien
1995-01-13 12:38 ` Laurent Gasser
1995-01-13 20:53 ` John DiCamillo
[not found] ` <3f8fnf$c8p@gamma.ois.com>
1995-01-16 11:02 ` Matt Kennel
[not found] ` <milodD2IFpG.329@netcom.com>
1995-01-17 21:39 ` R. William Beckwith
[not found] ` <3fa11q$sdh@gnat.cs.nyu.edu>
1995-01-16 20:20 ` David Moore
1995-01-14 0:24 ` David O'Brien
1995-01-20 4:43 ` Samuel Mize
1995-01-21 20:28 ` David O'Brien
1995-01-22 21:12 ` Robert Dewar
1995-01-23 18:35 ` Norman H. Cohen
1995-01-23 19:18 ` John Cosby - The Coz
1995-01-24 14:11 ` Samuel Mize
1995-01-14 10:37 ` Keith Thompson
[not found] ` <3fcjgt$b0v@cronkite.seas.gwu.edu>
1995-01-16 18:47 ` Robert Dewar
[not found] ` <D2It0r.4rp@inmet.camb.inmet.com>
1995-01-17 14:11 ` Norman H. Cohen
1994-12-30 16:06 Mitch Gart
1995-01-03 19:04 ` whiting_ms@corning.com (Matt Whiting)
1995-01-05 4:31 ` Michael Feldman
1995-01-04 21:40 ` Fred McCall
1995-01-05 4:30 ` Richard Pattis
1995-01-05 16:07 ` Kevin Weise
1995-01-06 13:06 ` Jahn Rentmeister
1995-01-06 16:47 ` Laurent Gasser
1995-01-06 17:29 ` David Weller
1995-01-06 17:30 ` David Weller
1995-01-10 18:28 ` Bob Kitzberger
1995-01-06 23:36 ` Kenneth Almquist
1995-01-04 22:45 ` Jay M. Martin
1995-01-05 4:37 ` Michael Feldman
1995-01-05 18:08 ` Jay Martin
1995-01-05 23:56 ` Robert Dewar
1995-01-08 8:04 ` Jay Martin
1995-01-06 0:07 ` Michael M. Bishop
1995-01-10 21:30 ` Jay Martin
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