[6087] in Athena Bugs
Saber msg: v2.1 (4/24/89 m1-238-4 vax Unix 4042 0)
daemon@ATHENA.MIT.EDU (lerman@ATHENA.MIT.EDU)
Fri Sep 21 11:52:35 1990
From: lerman@ATHENA.MIT.EDU
Date: Fri, 21 Sep 90 11:51:44 -0400
To: bugs@ATHENA.MIT.EDU
Cc: agbayani@ATHENA.MIT.EDU, ashok@ATHENA.MIT.EDU, chess@ATHENA.MIT.EDU,
In using Saber-C (and particularly xsaber) in my introductory
computer methods subject at MIT, I have found the following problems:
1. Saber doesn't accept the declaration "long double", even when the nsi
(ANSI) option is set.
2. In xsaber- When you issue the run command with an argument list,
it is impossible to erase ealier argument lists. For example, if you
enter run >myoutput, then subsequent run commands always add the
>myoutput argument. This is probably an initialization problem. The
only way I have found to get out of it is to quit xsaber and start
again. (The same thing occurs when you use the start command.)
3. With the ANSI option set, arithmetic operations on two floats
should produce a float. Saber produces a double. This bug was reported
by my earlier.
4. xsaber issues a variety of error messages in the window in which
it was started.These confuse beginning programmers. The messages
appear to be internal error messages, perhaps from when the xsaber
interface was being debugged.
5. xsaber doesn't seem to work with the twm and vtmw window managers.
This may be the fault of those window managers, or it may be an xsaber
problem.
6. The fact that xsaber doesn't highlight selections that go into
the cut buffer can create problems, particularly since some
commands activated from the command button automatically append the
contents of the cut buffer to the command. For example,
if you have something in the cut buffer and you press the run
button, you get the command run followed by the contents of the
cut buffer in the work space. This, combined with bug #2, can drive people crazy.
7. If you issue an action command on a variable and try to use that variable
in the action, saber complains that the variabe is
inactive. However, if you check the variable in the source window
by shift-clicking on it, saber states that the variable
is in fact active.
8. Although I have not personally verified this, one of my
teaching assistants has had the xsaber application corrupted when
running a program that has bugs in it. This occurred when the bugs
involved incorrect uses of pointers, suggesting the possibility
that parts of the application (or memory used by the application)
were being overwritten by the C program Saber is executing.
Since I have not received a reply to my earlier bug reports, I
do not know whether or not they were received. I'd appreciate a
reply to this message of the form, "We got your mail message."
Steven R. Lerman
lerman@athena.mit.edu
