* Re: PL/I is a viable language
@ 2003-02-23 1:26 robin
2003-02-23 2:27 ` Glen Herrmannsfeldt
0 siblings, 1 reply; 6+ messages in thread
From: robin @ 2003-02-23 1:26 UTC (permalink / raw)
Preben Randhol <randhol+news@pvv.org> writes: > Hyman Rosen wrote:
> > Nope. I'm just objecting to "If it broke, and it's C++, it's the
> > language's fault. If it broke, and it's Ada, it's the programmer's
> > fault."
>
> No, error are always the programmers fault. However some languages like
> Ada makes it much harder to make common simple mistakes (not logical
> mistakes mind you) than other languages whoes design more or less
> encourage these mistakes. This leaves the programmer more time to work
> on reviewing the code to find the complex mistakes. One of the nice
> things with Ada is that you hardly need to use a debugger on smaller
> projects (on big projects I don't know as I don't have experience with
> this). But for C/C++ you sure have to use a debugger at some stage even
> in small projects. Looking for the needle in the haystack takes a long
> time compared to having the compiler tell you both the location of the
> haystack and where the needle is/was last seen.
PL/I tells you where the needle actually is.
> --
> Preben Randhol ---------------- http://www.pvv.org/~randhol/ --
> "Violence is the last refuge of the incompetent", Isaac Asimov
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: PL/I is a viable language
2003-02-23 1:26 PL/I is a viable language robin
@ 2003-02-23 2:27 ` Glen Herrmannsfeldt
2003-02-23 17:58 ` GerardS
0 siblings, 1 reply; 6+ messages in thread
From: Glen Herrmannsfeldt @ 2003-02-23 2:27 UTC (permalink / raw)
"robin" <robin_v@bigpond.mapson.com> wrote in message news:OqV5a.53545
(snip regarding the ability to find errors in programs)
>
> PL/I tells you where the needle actually is.
>
On the 360/91 it told you where the error was near.
-- glen
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: PL/I is a viable language
2003-02-23 2:27 ` Glen Herrmannsfeldt
@ 2003-02-23 17:58 ` GerardS
2003-02-24 3:08 ` John W. Kennedy
0 siblings, 1 reply; 6+ messages in thread
From: GerardS @ 2003-02-23 17:58 UTC (permalink / raw)
| Glen Herrmannsfeldt wrote:
|| robin wrote:
| (snip regarding the ability to find errors in programs)
|> PL/I tells you where the needle actually is.
| On the 360/91 it told you where the error was near.
PL/I had an option (for the 360/91) to identify the
correct PL/I statement. One method was to put an extra
semicolon at the end of each statement (or those
statements that were likely to cause an error).
_______________________________________________Gerard S.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: PL/I is a viable language
2003-02-23 17:58 ` GerardS
@ 2003-02-24 3:08 ` John W. Kennedy
2003-02-26 1:19 ` Richard Shetron
0 siblings, 1 reply; 6+ messages in thread
From: John W. Kennedy @ 2003-02-24 3:08 UTC (permalink / raw)
GerardS wrote:
> | Glen Herrmannsfeldt wrote:
> || robin wrote:
> | (snip regarding the ability to find errors in programs)
> |> PL/I tells you where the needle actually is.
>
> | On the 360/91 it told you where the error was near.
>
> PL/I had an option (for the 360/91) to identify the
> correct PL/I statement. One method was to put an extra
> semicolon at the end of each statement (or those
> statements that were likely to cause an error).
At the cost of slowing the 91 down to a 75. It meant issuing the
BCR 15,0
(flush pipeline) instruction.
By the way, all this also applied to the 360/95, 360/195, and 370/195.
--
John W. Kennedy
"The poor have sometimes objected to being governed badly;
the rich have always objected to being governed at all."
-- G. K. Chesterton, "The Man Who Was Thursday"
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: PL/I is a viable language
2003-02-24 3:08 ` John W. Kennedy
@ 2003-02-26 1:19 ` Richard Shetron
2003-02-26 16:36 ` Glen Herrmannsfeldt
0 siblings, 1 reply; 6+ messages in thread
From: Richard Shetron @ 2003-02-26 1:19 UTC (permalink / raw)
In article <q0g6a.538999$HG.95100948@news4.srv.hcvlny.cv.net>,
John W. Kennedy <jwkenne@attglobal.net> wrote:
>GerardS wrote:
>> | Glen Herrmannsfeldt wrote:
>> || robin wrote:
>> | (snip regarding the ability to find errors in programs)
>> |> PL/I tells you where the needle actually is.
>>
>> | On the 360/91 it told you where the error was near.
>>
>> PL/I had an option (for the 360/91) to identify the
>> correct PL/I statement. One method was to put an extra
>> semicolon at the end of each statement (or those
>> statements that were likely to cause an error).
>
>At the cost of slowing the 91 down to a 75. It meant issuing the
> BCR 15,0
>(flush pipeline) instruction.
>
>By the way, all this also applied to the 360/95, 360/195, and 370/195.
This was not a PL/1 problem, but a problem with the underlaying
hardware. These were early pipelined machines where an error in
the pipeline wasn't readily tracked back to actually offending
instruction. If the hardware can't report the correct program
counter for errors, the software can't do more then guess.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: PL/I is a viable language
2003-02-26 1:19 ` Richard Shetron
@ 2003-02-26 16:36 ` Glen Herrmannsfeldt
0 siblings, 0 replies; 6+ messages in thread
From: Glen Herrmannsfeldt @ 2003-02-26 16:36 UTC (permalink / raw)
"Richard Shetron" <multics@neroon.user.acm.cs.rpi.edu> wrote in message
news:b3h4na$nro$1@newsfeeds.rpi.edu...
(snip)
> >
> >At the cost of slowing the 91 down to a 75. It meant issuing the
> > BCR 15,0
> >(flush pipeline) instruction.
> >
> >By the way, all this also applied to the 360/95, 360/195, and 370/195.
>
> This was not a PL/1 problem, but a problem with the underlaying
> hardware. These were early pipelined machines where an error in
> the pipeline wasn't readily tracked back to actually offending
> instruction. If the hardware can't report the correct program
> counter for errors, the software can't do more then guess.
Well, they were a problem for PL/I because PL/I tried. Other languages gave
up and let the system handle it.
There is an error message in PL/I (F) that changes from ERROR AT to ERROR
NEAR when the M91 option is on. I believe the BCR 15,0 are only added if
STMT option is on, so that statement numbers are reported in messages.
-- glen
^ permalink raw reply [flat|nested] 6+ messages in thread
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2003-02-23 1:26 PL/I is a viable language robin
2003-02-23 2:27 ` Glen Herrmannsfeldt
2003-02-23 17:58 ` GerardS
2003-02-24 3:08 ` John W. Kennedy
2003-02-26 1:19 ` Richard Shetron
2003-02-26 16:36 ` Glen Herrmannsfeldt
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