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<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-GB
style='font-size:10.0pt;font-family:Arial;color:navy'>hmm, the problem is
different IMO,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-GB
style='font-size:10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-GB
style='font-size:10.0pt;font-family:Arial;color:navy'>**corrected, but still
wrong**<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-GB
style='font-size:10.0pt;font-family:Arial;color:navy'>(IdentitySet withAll: #(1
1.0)) collect: [:e| e asInteger ] IdentitySet(1 )<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-GB
style='font-size:10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-GB
style='font-size:10.0pt;font-family:Arial;color:navy'>collect: should always
preserve the size of the original collection so it must return an
OrderedCollection !<o:p></o:p></span></font></p>
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<p class=MsoNormal><b><font size=2 face=Tahoma><span style='font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>Von:</span></font></b><font size=2
face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'>
squeak-dev-bounces@lists.squeakfoundation.org
[mailto:squeak-dev-bounces@lists.squeakfoundation.org] <b><span
style='font-weight:bold'>Im Auftrag von </span></b>Eliot Miranda<br>
<b><span style='font-weight:bold'>Gesendet:</span></b> Mittwoch, 26. November
2014 22:57<br>
<b><span style='font-weight:bold'>An:</span></b> <st1:PersonName w:st="on">The
general-purpose Squeak developers list</st1:PersonName><br>
<b><span style='font-weight:bold'>Betreff:</span></b> Re: [squeak-dev]
IdentitySet>>collect:</span></font><o:p></o:p></p>
</div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>On Wed, Nov 26, 2014 at 1:26 PM, Levente Uzonyi <<a
href="mailto:leves@elte.hu" target="_blank">leves@elte.hu</a>> wrote:<o:p></o:p></span></font></p>
<div>
<div>
<p class=MsoNormal style='margin-bottom:12.0pt'><font size=3
face="Times New Roman"><span style='font-size:12.0pt'>On Wed, 26 Nov 2014,
David T. Lewis wrote:<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>On Wed, Nov 26, 2014 at 08:01:49PM +0100, Levente Uzonyi wrote:<o:p></o:p></span></font></p>
<p class=MsoNormal style='margin-bottom:12.0pt'><font size=3
face="Times New Roman"><span style='font-size:12.0pt'>On Wed, 26 Nov 2014,
Eliot Miranda wrote:<o:p></o:p></span></font></p>
<p class=MsoNormal style='margin-bottom:12.0pt'><font size=3
face="Times New Roman"><span style='font-size:12.0pt'>Hi All,<br>
? ? IdentitySet>>collect: answers a Set, not an IdentitySet.? Anyone else<br>
agree this is a serious bug?? Anyone else disagree?<br>
<br>
WTF??<br>
<br>
(IdentitySet withAll: #(1 2 3 1.0 2.0 3.0)) collect: [:e| e] a Set(1.0 2 3)<br>
--<br>
best,Eliot<o:p></o:p></span></font></p>
<p class=MsoNormal style='margin-bottom:12.0pt'><font size=3
face="Times New Roman"><span style='font-size:12.0pt'><br>
Sometimes it's feasable to return an IdentitySet, other times it's not, so<br>
there's no optimal solution - #collect: can't cover all cases.<br>
<br>
Set >> #collect: explicitly returns a Set, because this is the least bad<br>
solution to handle all of its subclasses reasonably well.<br>
In case of WeakSet, returning a WeakSet makes no sense, because some of<br>
your objects will disappear immediately.<br>
In case of IdentitySet, PluggableSet, KeyedSet and KeyedIdentitySet the<br>
returned values may not behave well in the original collection.<br>
<br>
The best is to always be explicit:<br>
<br>
(IdentitySet withAll: #(1 2 3 1.0 2.0 3.0)) collect: [ :e | e ] as:<br>
IdentitySet<br>
"==> an IdentitySet(1 2 3 1.0 2.0 3.0)"<br>
<br>
Levente<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><br>
In Squeak 2.8 (checked on <a
href="http://bertfreudenberg.github.io/SqueakJS/run/" target="_blank">http://bertfreudenberg.github.io/SqueakJS/run/</a>):<br>
<br>
(IdentitySet withAll: #(1 2 3 1.0 2.0 3.0)) collect: [:e| e] ==> a
Set(2.0 1 2 3 3.0 1.0)<br>
<br>
<br>
But in trunk I get this:<br>
<br>
(IdentitySet withAll: #(1 2 3 1.0 2.0 3.0)) collect: [:e| e] ==> a
Set(1 2 3)<br>
<br>
<br>
So answering a Set makes sense for the reasons that Levente explains, but trunk<br>
is definitely broken WRT the contents of that set.<br>
<br>
This bug needs a unit test to go along with whatever fix we agree on.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
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<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>It's not a bug either. The Floats are not there, because they are equal
to the integers:<br>
<br>
1 = 1.0 "==> true"<br>
1.0 = 1 "==> true"<br>
<br>
Therefore they have the same hash:<br>
<br>
1 hash "==> 1"<br>
1.0 hash "==> 1"<br>
<br>
The bug was in Squeak 2.8:<br>
1.0 = 1 "==> true"<br>
1 = 1.0 "==> true"<br>
1 hash "==> 1"<br>
1.0 hash "==> 61440"<br>
<br>
Here's the comment of Float >> hash from The Trunk:<br>
"Hash is reimplemented because = is
implemented. Both words of the float are used. (The bitShift:'s ensure that the
intermediate results do not become a large integer.) Care is taken to answer
same hash as an equal Integer."<o:p></o:p></span></font></p>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
</div>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Exactly.<o:p></o:p></span></font></p>
</div>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
</div>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>My hope would be something like this (Set order is arbitrary)<o:p></o:p></span></font></p>
</div>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
</div>
<div>
<p class=MsoNormal><font size=3 color="#500050" face="Times New Roman"><span
style='font-size:12.0pt;color:#500050'>
((IdentitySet withAll: #(1 2 3 1.0 2.0 3.0)) collect: [:e| e]) =>
IdentitySet (1 2 3 1.0 2.0 3.0)</span></font><o:p></o:p></p>
</div>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
</div>
<div>
<p class=MsoNormal><font size=3 color="#500050" face="Times New Roman"><span
style='font-size:12.0pt;color:#500050'>but that</span></font><o:p></o:p></p>
</div>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> <font color="#500050"><span style='color:#500050'>
(Set withAll: #(1 2 3 1.0 2.0 3.0)) => Set (1 2 3)</span></font><o:p></o:p></span></font></p>
</div>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
</div>
<div>
<p class=MsoNormal><font size=3 color="#500050" face="Times New Roman"><span
style='font-size:12.0pt;color:#500050'>(and it always contains just the
integers since these are added first).</span></font><o:p></o:p></p>
</div>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
</div>
<div>
<p class=MsoNormal><font size=3 color="#500050" face="Times New Roman"><span
style='font-size:12.0pt;color:#500050'>But Levente's collect:as: solution is
perfectly acceptable and as he points out has the advantage of being explicit.</span></font><o:p></o:p></p>
</div>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
</div>
<blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;
margin-left:4.8pt;margin-right:0cm'>
<p class=MsoNormal style='margin-bottom:12.0pt'><font size=3
face="Times New Roman"><span style='font-size:12.0pt'><br>
Levente<o:p></o:p></span></font></p>
<p class=MsoNormal style='margin-bottom:12.0pt'><font size=3
face="Times New Roman"><span style='font-size:12.0pt'><br>
Dave<br>
<br>
<br>
<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
</blockquote>
</div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><br>
<br clear=all>
<o:p></o:p></span></font></p>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
</div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>-- <o:p></o:p></span></font></p>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>best,<o:p></o:p></span></font></p>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Eliot<o:p></o:p></span></font></p>
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