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Re: [Pharo-users] Why can't a Bag answer as a dictionary?

by phil＠highoctane.be

And when asking the object: #(1 2 4 5 6 7 2 1 4 3) asBag isDictionary we get false. So, not, not a dictionary. I still have been using #valuesAndCounts to get the dictionary out of a bag on several occasions. And is useful indeed. #(1 2 4 5 6 7 2 1 4 3) asBag occurrencesOf: 2 and #(1 2 4 5 6 7 2 1 4 3) asBag valuesAndCounts at: 2 seem pretty much the same. But in this age of streams/reactive streams and lazy evaluations, what do we have in Pharo on that front? Phil On Wed, Mar 6, 2019 at 4:49 PM Sven Van Caekenberghe <sven(a)stfx.eu> wrote: > I was just explaining how it is now, what I think the rationale is behind > it. > > I understand #asDictionary as working on a collection of > pairs/associations (because it basically goes to #withAll:). > > A bag is just a collection that is optimised for many duplicates, the fact > that you have values and counts is more an implementation detail than an > intrinsic property. > > The conversion that you want, and that already exists in #valuesAndCounts > is one interpretation of what a bag is, not the only one. A bag is foremost > a collection of things. > > I am not immediately convinced that #valuesAndCounts should be the default > #asDictionary interpretation. > > What about the inverse for example ? > > { #foo->2. #bar->3 } asDictionary asBag. > > But this is certainly an interesting discussion. > > > On 6 Mar 2019, at 16:23, Tim Mackinnon <tim(a)testit.works> wrote: > > > > As Richard said - as a bag is relationship between keys and frequencies, > I would expect it to be able to convert to a dictionary. > > > > It displays in an inspector just like a Dictionary - which is why I > figured I could convert to pass it back to the exercise that was written > with Dictionaries in mind. > > > > <PastedGraphic-3.png> > > > > > > The code to fix it is quite simple, but on these kinds of things - I > thought it worth checking before submitting a PR. > > > > Tim > > > > > >> On 6 Mar 2019, at 13:53, Sven Van Caekenberghe <sven(a)stfx.eu> wrote: > >> > >> Why would that work ? What would you expect the output to be ? > >> > >> Try: > >> > >> #(1 2 3) asDictionary > >> > >> it fails in exactly the same way. You need key/value pairs > (Associations). > >> > >> These do work > >> > >> Bag new add: #foo->100; asDictionary. > >> > >> Bag new addAll: 'ABABABAAAA'; valuesAndCounts. > >> > >>> On 6 Mar 2019, at 14:25, Tim Mackinnon <tim(a)testit.works> wrote: > >>> > >>> I was surprised to find that a Bag canât convert to a dictionary - e.g. > >>> > >>> Bag new > >>> addAll: 'aabbbbcdddâ; > >>> asDictionary > >>> > >>> Gives an error - Dnu #key > >>> > >>> > >>> It looks to me like Bag is inheriting a bad version of > #associationsDo: and instead could simply forward it to #doWithOccurences: > instead? > >>> > >>> I know Bag is not used that much - but it comes up a lot in > programming exercises. > >>> > >>> Tim > >> > >> > > > > > >

March 6, 2019

Re: [Pharo-users] IMAP in Pharo

by Tim Mackinnon

> On 6 Mar 2019, at 16:08, Sean P. DeNigris <sean(a)clipperadams.com> wrote: > > cedreek wrote >> Still havent get my head around this FORK/PR cycle but I will for sure one >> day :) > > It took me quite a while to grok. Fork = 'personal remote clone' and: [ PR = > 'UI support for discussing, testing, and accepting commits' ] It took me even longer to realise that when you load your master branch - you still need to pull changes from the original unforked repository (into your local repository) and then push them back up to your fork, AND then branch to make a change. For ages I was was getting unrelated diff changes even though I thought I had started on âmasterâ. Iâm hoping there will be a talk about all of this at Pharo Days. When you get it right its awesome - but when you take a mis-step its quite confusing until you realise what the pieces mean. (And Iâm sure I still have the model wrong, but its fun learning more each day) Tim

March 6, 2019

Re: [Pharo-users] How exactly is "share repositories between images" supposed to work without tripping each other up?

by Sean P. DeNigris

Tim Mackinnon wrote > how is this shared repository supposed to work? While I initially liked the space efficiency of the shared approach, I eventually gave up because it created too many (often obscure) problems. It just doesn't seem to be a good match for git, although you can get away with it in the simplest cases (read-only, no branch switching). It sounds like you may not have the luxury of avoiding it so hopefully someone can provide more constructive help. ----- Cheers, Sean -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html

March 6, 2019

Re: [Pharo-users] Serializing classes with Fuel

by Konrad Hinsen

Hi Mariano, > Yes, that's the "default" behavior. To fully serialize classes you need > FuelMetalevel packages. This brings a new visitors and mappers to allow you > to fully serialize methods, classes, contexts, etc. Thanks for the pointer - I will explore FuelMetalevel. Konrad.

March 6, 2019

Re: [Pharo-users] IMAP in Pharo

by Sean P. DeNigris

cedreek wrote > Still havent get my head around this FORK/PR cycle but I will for sure one > day :) It took me quite a while to grok. Fork = 'personal remote clone' and: [ PR = 'UI support for discussing, testing, and accepting commits' ] ----- Cheers, Sean -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html

March 6, 2019

Re: [Pharo-users] Why can't a Bag answer as a dictionary?

by Sven Van Caekenberghe

I was just explaining how it is now, what I think the rationale is behind it. I understand #asDictionary as working on a collection of pairs/associations (because it basically goes to #withAll:). A bag is just a collection that is optimised for many duplicates, the fact that you have values and counts is more an implementation detail than an intrinsic property. The conversion that you want, and that already exists in #valuesAndCounts is one interpretation of what a bag is, not the only one. A bag is foremost a collection of things. I am not immediately convinced that #valuesAndCounts should be the default #asDictionary interpretation. What about the inverse for example ? { #foo->2. #bar->3 } asDictionary asBag. But this is certainly an interesting discussion. > On 6 Mar 2019, at 16:23, Tim Mackinnon <tim(a)testit.works> wrote: > > As Richard said - as a bag is relationship between keys and frequencies, I would expect it to be able to convert to a dictionary. > > It displays in an inspector just like a Dictionary - which is why I figured I could convert to pass it back to the exercise that was written with Dictionaries in mind. > > <PastedGraphic-3.png> > > > The code to fix it is quite simple, but on these kinds of things - I thought it worth checking before submitting a PR. > > Tim > > >> On 6 Mar 2019, at 13:53, Sven Van Caekenberghe <sven(a)stfx.eu> wrote: >> >> Why would that work ? What would you expect the output to be ? >> >> Try: >> >> #(1 2 3) asDictionary >> >> it fails in exactly the same way. You need key/value pairs (Associations). >> >> These do work >> >> Bag new add: #foo->100; asDictionary. >> >> Bag new addAll: 'ABABABAAAA'; valuesAndCounts. >> >>> On 6 Mar 2019, at 14:25, Tim Mackinnon <tim(a)testit.works> wrote: >>> >>> I was surprised to find that a Bag canât convert to a dictionary - e.g. >>> >>> Bag new >>> addAll: 'aabbbbcdddâ; >>> asDictionary >>> >>> Gives an error - Dnu #key >>> >>> >>> It looks to me like Bag is inheriting a bad version of #associationsDo: and instead could simply forward it to #doWithOccurences: instead? >>> >>> I know Bag is not used that much - but it comes up a lot in programming exercises. >>> >>> Tim >> >> >

March 6, 2019

Re: [Pharo-users] How exactly is "share repositories between images" supposed to work without tripping each other up?

by Tim Mackinnon

While, Iâm still interested in how share repositories works (and debunk some of my myths about it ) - digging into this users issue (isnât Fuel wonderful) - it would seem that this image wasnât created with share repositories on. It looking down a very complicated stack (Metacello is very complicated) - it seems like a âlocalGopherâ object has an IceMetacelloRepositoryAdaptor in it that has this non-existent path? It seems like it gets this path from reading packages - but heck if I know how it ended up with something that wasnât on the users file system (although they did have an image like that at some point previous). Anyway - if it jumps out at someone - Iâd be interested, but otherwise will let it go for now. Tim > On 6 Mar 2019, at 09:26, Tim Mackinnon <tim(a)testit.works> wrote: > > Hi - as many windows users have struggled with the long file path problem (some of which can be caused by orphaned files not even referenced in your baseline - but that were checked in) - many users have started using the "share repositories between imagesâ and point it to a nice short file path (at least we have a workaround). > > This got us running on Exercism - and unblocked our testers. > > However - I was suprised when I asked one of our users to update his image to pull in some new code that fixed an issue for him (Itâs the first time I've encountered a conflict and had to use onConflict - and Iâm not sure why there is a conflict - but thats a side point). > > Metacello new > baseline: 'Exercism'; > repository: 'github://exercism/pharo-smalltalk:master/dev/src <github://exercism/pharo-smalltalk:master/dev/src>'; > onConflict: [ :ex | ex allow ]; > load. > > > So doing the above on OSX loads the update into my older image, and everything was fine. However on Windows - one of my testers tried the same thing and got a strange error: > âNotFound: failed to resolve path âC:\pharo\images\Exercism test\pharo-localâ¦.â (See photo below). > > The weird bit is that we arenât sure where the âExercism testâ bit comes from because his image isnât "Exercism testâ - however I suspect that this is one of the other images he created when we were testing 64 bit and he was loading into that. > > So my question is - how is this shared repository supposed to work? It seems to me that different images are storing non-sharable information in the repository such that sharing canât possibly work? As my baseline and setup are really simple - Iâm suprised by this - there is literally 4 packages and one external dependency on OSProcess (which is an mcz I think). So why does this fail? Iâve always avoided the shared repository as when I initially tried it, I recall all kinds of weird behaviour - but as the windows folks canât seem to avoid it - can someone explain what it does and what we need to look out for? > > Tim > <PastedGraphic-2.png>

March 6, 2019

Re: [Pharo-users] Why can't a Bag answer as a dictionary?

by Tim Mackinnon

As Richard said - as a bag is relationship between keys and frequencies, I would expect it to be able to convert to a dictionary. It displays in an inspector just like a Dictionary - which is why I figured I could convert to pass it back to the exercise that was written with Dictionaries in mind. The code to fix it is quite simple, but on these kinds of things - I thought it worth checking before submitting a PR. Tim > On 6 Mar 2019, at 13:53, Sven Van Caekenberghe <sven(a)stfx.eu> wrote: > > Why would that work ? What would you expect the output to be ? > > Try: > > #(1 2 3) asDictionary > > it fails in exactly the same way. You need key/value pairs (Associations). > > These do work > > Bag new add: #foo->100; asDictionary. > > Bag new addAll: 'ABABABAAAA'; valuesAndCounts. > >> On 6 Mar 2019, at 14:25, Tim Mackinnon <tim(a)testit.works> wrote: >> >> I was surprised to find that a Bag canât convert to a dictionary - e.g. >> >> Bag new >> addAll: 'aabbbbcdddâ; >> asDictionary >> >> Gives an error - Dnu #key >> >> >> It looks to me like Bag is inheriting a bad version of #associationsDo: and instead could simply forward it to #doWithOccurences: instead? >> >> I know Bag is not used that much - but it comes up a lot in programming exercises. >> >> Tim > >

March 6, 2019

Re: [Pharo-users] Why can't a Bag answer as a dictionary?

by Richard O'Keefe

Doubtless the original poster expected aBag asDictionary to answer a dictionary mapping the (distinct) elements of the bag to their counts. Mathematically, a bag can usefully be seen as a partial function from a set U to the positive integers, and a dictionary with U keys and positive integer values is precisely that. It's really not unreasonable to expect that, considering that there *is* a method that does just what the OP wanted: #valuesAndCounts. It's rather dangerous to expose private state like that, but it is not a private method. I would expect asDictionary ^contents copy On Thu, 7 Mar 2019 at 02:54, Sven Van Caekenberghe <sven(a)stfx.eu> wrote: > Why would that work ? What would you expect the output to be ? > > Try: > > #(1 2 3) asDictionary > > it fails in exactly the same way. You need key/value pairs (Associations). > > These do work > > Bag new add: #foo->100; asDictionary. > > Bag new addAll: 'ABABABAAAA'; valuesAndCounts. > > > On 6 Mar 2019, at 14:25, Tim Mackinnon <tim(a)testit.works> wrote: > > > > I was surprised to find that a Bag canât convert to a dictionary - e.g. > > > > Bag new > > addAll: 'aabbbbcdddâ; > > asDictionary > > > > Gives an error - Dnu #key > > > > > > It looks to me like Bag is inheriting a bad version of #associationsDo: > and instead could simply forward it to #doWithOccurences: instead? > > > > I know Bag is not used that much - but it comes up a lot in programming > exercises. > > > > Tim > > >

March 6, 2019

Re: [Pharo-users] Noob Question - slicing

by K K Subbu

> On Wed, 6 Mar 2019 at 12:00, Craig Johnson <craig(a)hivemind.net > <mailto:craig@hivemind.net>> wrote: > What is the simplest way to copy characters between positions 4 and > 8 from a string in Pharo?____ '1234567890' copyFrom: 5 to: 8 "5678" Page 207 in Updated Pharo by Example book explains more on substrings. HTH .. Subbu

March 6, 2019