From: david@kdbarto.org (David)
Subject: [TUHS] Array index history
Date: Thu, 8 Jun 2017 11:20:24 -0700 [thread overview]
Message-ID: <09918D02-9DA7-46B8-873E-A60489570400@kdbarto.org> (raw)
In-Reply-To: <mailman.882.1496854900.3779.tuhs@minnie.tuhs.org>
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Arnold gets it right on the Pascal indexing.
In UCSD Pascal you could specify any array bounds you would like and
the compiler would 0 base them for you by always doing a subtraction,
or addition if your min was negative, of your min array index. So a little
run time cost for non-zero based arrays.
I’m not sure how other Pascal compilers did this.
I find it interesting that there are now a slew of testing programs
(Valgrind, Address Sanitizer, Purify, etc) that will add the ‘missing’
array bounds checking for C.
David
> On Jun 7, 2017, at 10:01 AM, tuhs-request at minnie.tuhs.org wrote:
>
> Date: Wed, 07 Jun 2017 07:20:43 -0600
> From: arnold at skeeve.com
> To: tuhs at tuhs.org, ag4ve.us at gmail.com
> Subject: Re: [TUHS] Array index history
> Message-ID: <201706071320.v57DKhmJ026303 at freefriends.org>
> Content-Type: text/plain; charset=us-ascii
>
> Pascal (IIRC) allowed you to specify upper and lower bounds, something
> like
>
> foo : array[5..10] of integer;
>
> with runtime bounds checking on array accesses. (I could be wrong ---
> it's been a LLLLOOONNNGGG time.)
>
> HTH,
>
> Arnold
next parent reply other threads:[~2017-06-08 18:20 UTC|newest]
Thread overview: 52+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <mailman.882.1496854900.3779.tuhs@minnie.tuhs.org>
2017-06-08 18:20 ` David [this message]
2017-06-08 18:55 ` Ron Natalie
2017-06-09 21:21 ` Steve Johnson
2017-06-09 21:52 ` Arthur Krewat
2017-06-08 22:29 ` Johnny Billquist
2017-06-08 23:16 ` Ron Natalie
2017-06-08 23:41 ` Steve Nickolas
2017-06-09 15:12 ` Random832
2017-06-09 16:30 ` Ron Natalie
2017-06-09 0:21 ` Johnny Billquist
2017-06-09 0:25 ` Pete Turnbull
2017-06-09 1:19 ` Toby Thain
2017-06-09 2:14 ` Pete Turnbull
[not found] <mailman.890.1496953026.3779.tuhs@minnie.tuhs.org>
2017-06-08 22:28 ` Johnny Billquist
2017-06-08 9:16 Richard Tobin
-- strict thread matches above, loose matches on Subject: below --
2017-06-08 2:27 Doug McIlroy
2017-06-08 12:49 ` William Cheswick
2017-06-08 12:56 ` Michael Kjörling
2017-06-08 13:45 ` Dan Cross
2017-06-08 13:57 ` Ron Natalie
2017-06-10 21:08 ` Nemo
2017-06-08 15:04 ` Dave Horsfall
2017-06-08 15:09 ` William Pechter
2017-06-08 16:53 ` Steve Nickolas
2017-06-08 20:17 ` Larry McVoy
2017-06-09 0:03 ` Greg 'groggy' Lehey
[not found] <CAH_OBiewwwS6kbdWKUO-j3v=Do+Y9AzBn4ZkyVic7LOJN5WX7w@mail.gmail.com>
[not found] ` <CAH_OBid5q-YeB6UYeOfjW68s3nb3TX_icC5dFMapfo=7_q5DUQ@mail.gmail.com>
[not found] ` <CAH_OBideJeNGiiys=VOEYcU1cffSg+6zDOD39HOU74vumQF0kA@mail.gmail.com>
[not found] ` <CAH_OBie_+dQXOC2OaZii5K=j1Ljmv-OvAVXvyypoLJ10jaysWA@mail.gmail.com>
[not found] ` <CAH_OBidXd1Lpgp8ttM3sWLfXDT0ms5EGAzEjPH9QkY+bXyev2w@mail.gmail.com>
[not found] ` <CAH_OBifge2RrwcDvSV46gwLAc0wHVtH++gdMBhXi-x8C0a_2jw@mail.gmail.com>
[not found] ` <CAH_OBic3MTy-20C_T2ciT2x+EjNZvXR2PJ0OzB0qRp1gd2OL-g@mail.gmail.com>
2017-06-07 12:56 ` shawn wilson
2017-06-07 13:16 ` Ron Natalie
2017-06-07 13:20 ` arnold
2017-06-07 13:50 ` Michael Kjörling
2017-06-07 14:02 ` arnold
2017-06-08 11:28 ` Christian Neukirchen
2017-06-08 14:56 ` shawn wilson
2017-06-07 14:58 ` Tony Finch
2017-06-07 23:57 ` Dave Horsfall
2017-06-07 16:31 ` Lyndon Nerenberg
2017-06-08 0:47 ` Bakul Shah
2017-06-07 17:59 ` Tim Bradshaw
2017-06-07 18:29 ` Clem Cole
2017-06-07 18:46 ` Arthur Krewat
2017-06-07 19:03 ` Ron Natalie
2017-06-07 19:15 ` Arthur Krewat
2017-06-07 19:49 ` Ron Natalie
2017-06-08 1:58 ` ARJANEN Loïc Jean David
2017-06-08 13:49 ` Random832
2017-06-08 13:55 ` Arthur Krewat
2017-06-08 18:41 ` Tim Bradshaw
2017-06-08 2:45 ` Robert Swierczek
2017-06-08 4:05 ` Dave Horsfall
2017-06-08 6:19 ` Peter Jeremy
2017-06-08 7:02 ` Dave Horsfall
2017-06-08 13:53 ` Ron Natalie
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