August 2012 - Pharo-dev - lists.pharo.org

Re: [Pharo-project] numLiterals > 0 is that possible?

by Mariano Martinez Peck

On Sat, Aug 18, 2012 at 1:02 PM, Frank Shearar <frank.shearar(a)gmail.com>wrote: > On 18 August 2012 11:57, Mariano Martinez Peck <marianopeck(a)gmail.com> > wrote: > > > > > > On Sat, Aug 18, 2012 at 12:33 PM, Camillo Bruni <camillobruni(a)gmail.com> > > wrote: > >> > >> > >> On 2012-08-17, at 22:50, Eliot Miranda <eliot.miranda(a)gmail.com> wrote: > >> > >> > On Fri, Aug 17, 2012 at 1:42 PM, Mariano Martinez Peck < > >> > marianopeck(a)gmail.com> wrote: > >> > > >> >> Hi guys. Right now we have > >> >> > >> >> methodClass > >> >> "answer the class that I am installed in" > >> >> ^self numLiterals > 0 > >> >> ifTrue: [ (self literalAt: self numLiterals) value ] > >> >> ifFalse: [ nil ] > >> >> > >> >> But of course my image has no method with 0 literals: > >> >> > >> >> (CompiledMethod allInstances select: [:each | each numLiterals = 0 ]) > >> >> size > >> >> -> 0 > >> >> > >> >> So...can this really happen? or I can just remove the if ? > >> >> > >> > > >> > Yes it could happen. For example, i the Newspeak implementation above > >> > Squeak these is a collection of inst-var accessors that are shared > >> > through > >> > all Newspeak classes in the system. > >> > >> so it will never happen in Pharo right? > >> > >> > These have a nil methodClass. If one > >> > wanted to save space they could have no methodClass instead of nil in > >> > the > >> > methodClass slot. (Note that the above works for these since nil > value > >> > = > >> > value). So IMO its a harmless piece of defensice programming. > IIABDFI > >> > (If > >> > it ain't broke don't fix it). > >> > >> again, this is not pharo mentality... > >> > > > > Yes, that was my point. Our system is full of "xx > yyy ifZZ:" , > > "isEmptyOrNil ifZZ:", "ifNil: " blah blah blah. I am sure lost of them > were > > workaround introduced to solve a problem in some point in time in the > last > > 20 years. And not only at a point in time, but also together with an > > specific image version, set of libraries, vm, etc. I am also sure lots of > > them may not be necessary anymore after so many cleanings and library > > replacement. Hence, my question. > > > > Finally, if Pharo would have followed the IIABDFI (If it ain't broke > don't > > fix it) then we would still have ReferenceStream, ImageSegment, > HTTPSocket, > > Preferences, FileDirectory, SystemChangeNotifier, and many others around > > (of course, someone could consider them as broken). > > Replacing something is not the same as removing things you think will > never happen. Oftentimes, yes, those crazy bits of nonsense were added > a decade ago _for very good reason_, even if the committe failed his > good citizenry test by documenting it. You can get yourself into very > nasty trouble by randomly fixing things that aren't broken. Especially > if you're not quite sure what the crazy nonsense is for. > Replacing something is not the same as removing, I agree. But if the hacks or workaround were for a particular very good reason and some point in time, with certain image and libraries, why to keep it NOW in Pharo? Say ReferenceStream had some hacks around the system. Now we have removed it. Why should we keep the hacks in Pharo itself? No problem if someone wants to install ReferenceStream again in Pharo. But if you do so, bring with you all the hacks/workarounds to make it work. We will not keep the garbage in the main image. Take this very example of #methodClass. Why would be need to keep the "self literals > 0" ? (if the reasons are what Eliot said). If then Newspeak wants to be built on top of Pharo, great, bring the changes (like this one) with you. Finally, I am not afraid/shame of rollbacking. I prefer to clean something and then discover that it was actually needed than do nothing. In fact, I would be able to document why it was needed ;) > > frank > > > -- > > Mariano > > http://marianopeck.wordpress.com > > > > -- Mariano http://marianopeck.wordpress.com

Aug. 18, 2012

Re: [Pharo-project] numLiterals > 0 is that possible?

by Frank Shearar

On 18 August 2012 11:57, Mariano Martinez Peck <marianopeck(a)gmail.com> wrote: > > > On Sat, Aug 18, 2012 at 12:33 PM, Camillo Bruni <camillobruni(a)gmail.com> > wrote: >> >> >> On 2012-08-17, at 22:50, Eliot Miranda <eliot.miranda(a)gmail.com> wrote: >> >> > On Fri, Aug 17, 2012 at 1:42 PM, Mariano Martinez Peck < >> > marianopeck(a)gmail.com> wrote: >> > >> >> Hi guys. Right now we have >> >> >> >> methodClass >> >> "answer the class that I am installed in" >> >> ^self numLiterals > 0 >> >> ifTrue: [ (self literalAt: self numLiterals) value ] >> >> ifFalse: [ nil ] >> >> >> >> But of course my image has no method with 0 literals: >> >> >> >> (CompiledMethod allInstances select: [:each | each numLiterals = 0 ]) >> >> size >> >> -> 0 >> >> >> >> So...can this really happen? or I can just remove the if ? >> >> >> > >> > Yes it could happen. For example, i the Newspeak implementation above >> > Squeak these is a collection of inst-var accessors that are shared >> > through >> > all Newspeak classes in the system. >> >> so it will never happen in Pharo right? >> >> > These have a nil methodClass. If one >> > wanted to save space they could have no methodClass instead of nil in >> > the >> > methodClass slot. (Note that the above works for these since nil value >> > = >> > value). So IMO its a harmless piece of defensice programming. IIABDFI >> > (If >> > it ain't broke don't fix it). >> >> again, this is not pharo mentality... >> > > Yes, that was my point. Our system is full of "xx > yyy ifZZ:" , > "isEmptyOrNil ifZZ:", "ifNil: " blah blah blah. I am sure lost of them were > workaround introduced to solve a problem in some point in time in the last > 20 years. And not only at a point in time, but also together with an > specific image version, set of libraries, vm, etc. I am also sure lots of > them may not be necessary anymore after so many cleanings and library > replacement. Hence, my question. > > Finally, if Pharo would have followed the IIABDFI (If it ain't broke don't > fix it) then we would still have ReferenceStream, ImageSegment, HTTPSocket, > Preferences, FileDirectory, SystemChangeNotifier, and many others around > (of course, someone could consider them as broken). Replacing something is not the same as removing things you think will never happen. Oftentimes, yes, those crazy bits of nonsense were added a decade ago _for very good reason_, even if the committe failed his good citizenry test by documenting it. You can get yourself into very nasty trouble by randomly fixing things that aren't broken. Especially if you're not quite sure what the crazy nonsense is for. frank > -- > Mariano > http://marianopeck.wordpress.com >

Aug. 18, 2012

Re: [Pharo-project] numLiterals > 0 is that possible?

by Mariano Martinez Peck

On Sat, Aug 18, 2012 at 12:33 PM, Camillo Bruni <camillobruni(a)gmail.com>wrote: > > On 2012-08-17, at 22:50, Eliot Miranda <eliot.miranda(a)gmail.com> wrote: > > > On Fri, Aug 17, 2012 at 1:42 PM, Mariano Martinez Peck < > > marianopeck(a)gmail.com> wrote: > > > >> Hi guys. Right now we have > >> > >> methodClass > >> "answer the class that I am installed in" > >> ^self numLiterals > 0 > >> ifTrue: [ (self literalAt: self numLiterals) value ] > >> ifFalse: [ nil ] > >> > >> But of course my image has no method with 0 literals: > >> > >> (CompiledMethod allInstances select: [:each | each numLiterals = 0 ]) > size > >> -> 0 > >> > >> So...can this really happen? or I can just remove the if ? > >> > > > > Yes it could happen. For example, i the Newspeak implementation above > > Squeak these is a collection of inst-var accessors that are shared > through > > all Newspeak classes in the system. > > so it will never happen in Pharo right? > > > These have a nil methodClass. If one > > wanted to save space they could have no methodClass instead of nil in the > > methodClass slot. (Note that the above works for these since nil value = > > value). So IMO its a harmless piece of defensice programming. IIABDFI > (If > > it ain't broke don't fix it). > > again, this is not pharo mentality... > > Yes, that was my point. Our system is full of "xx > yyy ifZZ:" , "isEmptyOrNil ifZZ:", "ifNil: " blah blah blah. I am sure lost of them were workaround introduced to solve a problem in some point in time in the last 20 years. And not only at a point in time, but also together with an specific image version, set of libraries, vm, etc. I am also sure lots of them may not be necessary anymore after so many cleanings and library replacement. Hence, my question. Finally, if Pharo would have followed the IIABDFI (If it ain't broke don't fix it) then we would still have ReferenceStream, ImageSegment, HTTPSocket, Preferences, FileDirectory, SystemChangeNotifier, and many others around (of course, someone could consider them as broken). -- Mariano http://marianopeck.wordpress.com

Aug. 18, 2012

Re: [Pharo-project] numLiterals > 0 is that possible?

by Camillo Bruni

On 2012-08-17, at 22:50, Eliot Miranda <eliot.miranda(a)gmail.com> wrote: > On Fri, Aug 17, 2012 at 1:42 PM, Mariano Martinez Peck < > marianopeck(a)gmail.com> wrote: > >> Hi guys. Right now we have >> >> methodClass >> "answer the class that I am installed in" >> ^self numLiterals > 0 >> ifTrue: [ (self literalAt: self numLiterals) value ] >> ifFalse: [ nil ] >> >> But of course my image has no method with 0 literals: >> >> (CompiledMethod allInstances select: [:each | each numLiterals = 0 ]) size >> -> 0 >> >> So...can this really happen? or I can just remove the if ? >> > > Yes it could happen. For example, i the Newspeak implementation above > Squeak these is a collection of inst-var accessors that are shared through > all Newspeak classes in the system. so it will never happen in Pharo right? > These have a nil methodClass. If one > wanted to save space they could have no methodClass instead of nil in the > methodClass slot. (Note that the above works for these since nil value = > value). So IMO its a harmless piece of defensice programming. IIABDFI (If > it ain't broke don't fix it). again, this is not pharo mentality...

Aug. 18, 2012

Re: [Pharo-project] numLiterals > 0 is that possible?

by Eliot Miranda

On Fri, Aug 17, 2012 at 1:42 PM, Mariano Martinez Peck < marianopeck(a)gmail.com> wrote: > Hi guys. Right now we have > > methodClass > "answer the class that I am installed in" > ^self numLiterals > 0 > ifTrue: [ (self literalAt: self numLiterals) value ] > ifFalse: [ nil ] > > But of course my image has no method with 0 literals: > > (CompiledMethod allInstances select: [:each | each numLiterals = 0 ]) size > -> 0 > > So...can this really happen? or I can just remove the if ? > Yes it could happen. For example, i the Newspeak implementation above Squeak these is a collection of inst-var accessors that are shared through all Newspeak classes in the system. These have a nil methodClass. If one wanted to save space they could have no methodClass instead of nil in the methodClass slot. (Note that the above works for these since nil value = value). So IMO its a harmless piece of defensice programming. IIABDFI (If it ain't broke don't fix it). > > thanks > > -- > Mariano > http://marianopeck.wordpress.com > > -- best, Eliot

Aug. 17, 2012

[Pharo-project] numLiterals > 0 is that possible?

by Mariano Martinez Peck

Hi guys. Right now we have methodClass "answer the class that I am installed in" ^self numLiterals > 0 ifTrue: [ (self literalAt: self numLiterals) value ] ifFalse: [ nil ] But of course my image has no method with 0 literals: (CompiledMethod allInstances select: [:each | each numLiterals = 0 ]) size -> 0 So...can this really happen? or I can just remove the if ? thanks -- Mariano http://marianopeck.wordpress.com

Aug. 17, 2012

Re: [Pharo-project] serializing DynamicVariables (Zinc so far)

by Mariano Martinez Peck

Hi Frank and Sean. The problem was quite hard to reproduce. You need to rebuild a Pharo image from a kernel using Tanker ;) Anyway, since we are changing completely Tanker now it may have been solved. I did a quick test (of a similar case) and it works. So once I have the example of the kernel again I will trying again. Thanks for offering the help! On Fri, Aug 17, 2012 at 2:33 PM, Sean P. DeNigris <sean(a)clipperadams.com>wrote: > > Mariano Martinez Peck wrote > > > > The first time, #enable answers something wrong. The second time it is > > called, it seems to answer the correct value. > > Mariano, would you give some more details about the wrong value, the > expected value, and the steps to reproduce? I took a look but I'm not > seeing > what the problem is... b.t.w. is this a 1.4 or 2.0 image? > > Sean > > > > -- > View this message in context: > http://forum.world.st/serializing-DynamicVariables-Zinc-so-far-tp4643514p46… > Sent from the Pharo Smalltalk mailing list archive at Nabble.com. > > -- Mariano http://marianopeck.wordpress.com

Aug. 17, 2012

[Pharo-project] [update 2.0] #20258

by Esteban Lorenzano

20258 ----- Issue 5870: [BUG] FileSystem>>rename:to: causes DNU http://code.google.com/p/pharo/issues/detail?id=5870

Aug. 17, 2012

[Pharo-project] Trying to understand Class >> category

by Mariano Martinez Peck

Hi guys. I need a category expert to explain why we have the following: Class >> category "Answer the system organization category for the receiver. First check whether the category name stored in the ivar is still correct and only if this fails look it up (latter is much more expensive)" | result | self basicCategory ifNotNil: [ :symbol | ((self environment organization listAtCategoryNamed: symbol) includes: self name) ifTrue: [ ^symbol ] ]. self basicCategory: (result := self environment organization categoryOfElement: self name). ^result So...how can a class store an "incorrect" category? Or in other words.... can PackageInfo >> includesClass: aClass ^ self includesSystemCategory: aClass theNonMetaClass category use #basicCategory (simple accessor) rather than #category? thanks, -- Mariano http://marianopeck.wordpress.com

Aug. 17, 2012

[Pharo-project] [update 2.0] #20257

by Esteban Lorenzano

20257 ----- Issue 3459: includesSubstring: aString caseSensitive: caseSensitive / includesSubString: http://code.google.com/p/pharo/issues/detail?id=3459 Issue 3518: #warningAllowed does not handle UndeclaredVariableWarning http://code.google.com/p/pharo/issues/detail?id=3518 Issue 6435: Spotlight gives an error message when asked for World: PasteUpMorph asNode DNU. http://code.google.com/p/pharo/issues/detail?id=6435 Issue 6501: Morph>>drawOnCanvas: does not seems used http://code.google.com/p/pharo/issues/detail?id=6501 Issue 6565: Fix #next:putAll:startingAt: for MultiByteFileStream http://code.google.com/p/pharo/issues/detail?id=6565

Aug. 17, 2012