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<div class="moz-cite-prefix">Sorry for the badly unretitled previous
message. May i end it with a suggestion:<br>
<br>
Le 09/03/2016 01:18, Samuel Gougeon a écrit :<br>
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<blockquote cite="mid:56DF6BCE.8000008@free.fr" type="cite">
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<div class="moz-cite-prefix">Hello,<br>
<br>
Le 18/02/2016 20:41, Eric Dubois a écrit :<br>
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<blockquote
cite="mid:CAGgDjFTioCjbgVMnMTUvVEEu+sGDHW1E=aPArDgwiS7qtWgm8w@mail.gmail.com"
type="cite">
<div dir="ltr">Hello
<div><br>
</div>
<div>I am inclined to share Samuel point of view: this is a
compliocation than could be avoided.</div>
<div><br>
</div>
<div>But I cannot resist noting that the annoucement is 6
years older than the announcement of the weapon of mass
destruction that consist in changing the behaviour of the
addition of a matrix with a null matrix.</div>
<div><br>
</div>
<div>Sorry for insisting, but I will again call for the
removal from the final Scilab 6.0 release of this planned
change.</div>
<div><br>
</div>
<div>First, I am not convinced at all by the argument put
forward that it will make Scilab more consistent with other
language such as Matlab, Octave, Julia.. : after all, every
language has its indiosycrasies; a Matlab user will yet have
to adapt herslef to this change, bu along many other ones;
and I,do not think that changing this behavour will convice
any Matlab user to switch to Scilab nor prevent anyone
thinking about switching to give up because of this
beahviour.</div>
<div><br>
</div>
<div>Second The argument that it enhances Scilab internal
consistency is a little bit more compelling, but not much:
after all, addition and subtraction are different operations
from multiplication and division, such one can justify
different behaviour. And there are cases when it make tho
code more compact.</div>
<div><br>
</div>
<div>Adnd lastly both arguments are anyway swept away by the
simple fact that the change should make all previous code
unreliable: you cannot be sure in advance that the working
of your program has not been affected by the change (and the
warning that is designed to alert to the user is not
sufficient: a warning can easily be missed, especially for
second hand users not so famaliar with Scilab and if it is
hidden among many other warnings).</div>
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<br>
I have the same feeling, and i agree mostly with your last remark.
We could stress on some "pitfalls" set by the <tt>oldEmptyBehaviour
flag or by the "warning stop"</tt> behavior:<tt><br>
</tt>
<ul>
<li><tt>oldEmptyBehaviour</tt> flag:<tt> </tt>We may guess that
this flag is a <i>global</i> one. Isn't it? So, if we set it
at the beginning of a script or of a macro, then it applies to
the whole Scilab session (i haven't checked that), even after
leaving the script or the macro. If so, then if in a session
we process some recent up-to-date scripts or macros, and some
other ones that are not up-to-date, what will occur, whatever
is the flag's value? This is not really clear.<br>
<br>
</li>
<li><tt>warning("stop")</tt>: i agree that, in order to update
all contents and to be sure that results are reliable and not
polluted by unpredictable "[]+-" side effects, this warning
mode will have to be always activated for a very long period,
may be up to Scilab 7. Then, the problem is that this stopping
mode does not resolve the cause: if an up-to-date package
intentionally uses warnings for anything else than []+, it
will be stopped as well. <br>
This warning mode should accept an additional parameter
identifying the type of event (or a series/vector of events)
for which stopping must occur. Shouln't it?</li>
</ul>
</blockquote>
<br>
For both of these reasons, introducing this <tt>oldEmptyBehaviour</tt>
flag in Scilab 6 is questionable. It might be preferable to only
improve the warning("stop", event) mode, and to leave Scilab 5.5.2
available on the download page for a long time. It will then always
be possible to run old packages with Scilab 5. <br>
<br>
SG<br>
<br>
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