April 2018 - Pharo-users - lists.pharo.org

Re: [Pharo-users] Literals

by ClÃ©ment Bera

The guy who asked the question said: "...when you want to shorten some object initialization" Using ClassVariable is an alternative way to shorten object initialization, reading a ClassVariable is almost the same performance as reading a literal, so that looked like a good alternative to me. Both the ClassVariable and the literal have the same issues (same object so if you mutate it you have to deal with it). But yes, it's not a new literal. For new literals, you can extend the compiler or hard patch thing: MyClass>>foo ^ #bar (MyClass>>#foo) literalAt: ((MyClass>>#foo) literals indexOf: #bar) put: Set new. MyClass new foo >>> a Set () Obviously it depends what you mean by literal, the latter code uses the literal bytecode instruction, which does not make the pushed object a literal object... On Fri, Apr 27, 2018 at 8:59 PM, Esteban A. Maringolo <emaringolo(a)gmail.com> wrote: > On 27/04/2018 15:35, Richard Sargent wrote: > > On Fri, Apr 27, 2018 at 2:08 PM, Esteban A. Maringolo > > <emaringolo(a)gmail.com <mailto:emaringolo@gmail.com>> wrote: > > > As far as I knew the only way to have new literals was to modify the > > compiler. > > > > > > Yes. > > > > VA Smalltalk has an interesting syntax extension which allows an > > arbitrary expression to be a compile-time literal. > > Going by memory, something like ##(Dictionary new at: #a put: self > > something; at: #b put: self somethingElse; yourself). > > Dolphin Smalltalk provides that ##() literal as well since a decade at > least, so you have the full expression that gave origin to that literal, > but you don't need to compute it every time it is accessed. > > Although I don't remember seeing it with Dictionaries, but more with > string concatenations or "magic numbers" like seconds in a day stored as > ##(24 * 60 * 60). > > Regards, > > > -- > Esteban A. Maringolo > > -- ClÃ©ment BÃ©ra https://clementbera.github.io/ https://clementbera.wordpress.com/

April 27, 2018

Re: [Pharo-users] Literals

by Esteban A. Maringolo

On 27/04/2018 15:35, Richard Sargent wrote: > On Fri, Apr 27, 2018 at 2:08 PM, Esteban A. Maringolo > <emaringolo(a)gmail.com <mailto:emaringolo@gmail.com>> wrote: > As far as I knew the only way to have new literals was to modify the > compiler. > > > Yes. > > VA Smalltalk has an interesting syntax extension which allows an > arbitrary expression to be a compile-time literal. > Going by memory, something like ##(Dictionary new at: #a put: self > something; at: #b put: self somethingElse; yourself). Dolphin Smalltalk provides that ##() literal as well since a decade at least, so you have the full expression that gave origin to that literal, but you don't need to compute it every time it is accessed. Although I don't remember seeing it with Dictionaries, but more with string concatenations or "magic numbers" like seconds in a day stored as ##(24 * 60 * 60). Regards, -- Esteban A. Maringolo

April 27, 2018

Re: [Pharo-users] Literals

by Richard Sargent

On Fri, Apr 27, 2018 at 2:08 PM, Esteban A. Maringolo <emaringolo(a)gmail.com> wrote: > Hi ClÃ©ment, > > On 27/04/2018 10:32, ClÃ©ment Bera wrote: > > Obviously sets are not as easy to deal with. You cannot mutate empty > > arrays/bytearrays, if you concatenate something it creates a new object. > > You can add things in sets. So you need to be careful... You can make > > the object read-only to avoid issues (MyClassVar beReadOnlyObject). > > Sorry, but I can't understand how a class variable could allow you to > use a new literal. > > As far as I knew the only way to have new literals was to modify the > compiler. > Yes. VA Smalltalk has an interesting syntax extension which allows an arbitrary expression to be a compile-time literal. Going by memory, something like ##(Dictionary new at: #a put: self something; at: #b put: self somethingElse; yourself). Of course, the problem with that is it will not change if the implementations of the messages it sends entail some changes over time. > So if you want #{} to create a new empty set, or #{1 1 2} to create a > Set with 1 and 2 as elements, there is no way to do it. > > Or this %{$a -> 1. 'foo' -> false. 'baz' -> #{1 1 2}} to create a > dictionary with such set as literal. :) > > Regards, > > -- > Esteban A. Maringolo > >

April 27, 2018

Re: [Pharo-users] Literals

by Esteban A. Maringolo

Hi ClÃ©ment, On 27/04/2018 10:32, ClÃ©ment Bera wrote: > Obviously sets are not as easy to deal with. You cannot mutate empty > arrays/bytearrays, if you concatenate something it creates a new object. > You can add things in sets. So you need to be careful... You can make > the object read-only to avoid issues (MyClassVar beReadOnlyObject). Sorry, but I can't understand how a class variable could allow you to use a new literal. As far as I knew the only way to have new literals was to modify the compiler. So if you want #{} to create a new empty set, or #{1 1 2} to create a Set with 1 and 2 as elements, there is no way to do it. Or this %{$a -> 1. 'foo' -> false. 'baz' -> #{1 1 2}} to create a dictionary with such set as literal. :) Regards, -- Esteban A. Maringolo

April 27, 2018

Re: [Pharo-users] SortedCollection>>reverse answers an inconsistent object in Pharo 6

by Richard O'Keefe

You wrote "In general reversed/converse has no meaning for block." That's entirely an artefact of representing blocks of different arities by the same class. In my own Smalltalk, NiladicBlock, MonadicBlock, DyadicBlock, ... are different classes. To put it another way, your statement has exactly the same status as "In general #value:value: has no meaning for block." #converse has meaning for *all* DyadicBlocks, it is the combinator flip f x y = f y x. For that matter, it could be generalised to all blocks of arity >= 2 as [:a1 :a2 ... :an | body] converse => [:a2 :a1 ... :an | body] i.e., flip the first two arguments. My original implementation of #converse was DyadicBlock methods for: 'combinators' converse ^[:x :y | self value: y value: x] "other combinators" With a suitable set of combinators, I can do things like #name ascending thenBy: #age descending thenBy: #weight ascending nilsFirst without needing a SortFunction class. âI do like the fact that SortFunction can support both 2-way and 3-wayâ comparison.

April 27, 2018

Re: [Pharo-users] UFFI - Could not coerce arguments

by Serge Stinckwich

On Fri, Apr 27, 2018 at 10:45 AM, Esteban Lorenzano <estebanlm(a)gmail.com> wrote: > hi, > > it all depends on how you are declaring your types. > > here, for example you are passing > > aTF_OutputArray getHandle > > thatâs a âvoid*â value (an ExternalAddress or ExternalData object), and in > declaration you have (if I read correctly): > > TF_Output * > > so, first question is: if TF_Output != void, then you have a coercing > problem :). > > âTF_Output != void, because this is a subclass of FFIOpaqueObject â > you can fix that just changing the notation to receive a void * (in C is > all the same, but not in pharo :)) > > note that this can be happening in a lot of places, since your function > has a lot of arguments, I just put an example of what can be wrong. > > â I try to replace all types by void* here: TF_Session>>runSession: aTF_Session options: opsTF_Buffer inputs: inTF_OutputArray values: inTF_TensorArray count: inCount outputs: outTF_OutputArray values: outTF_TensorArrayPtr count: outCount targets: aTF_OperationArray count: targetCount metadata: metaTF_Buffer status: aTF_Status "F_CAPI_EXPORT extern void TF_SessionRun( TF_Session* session, // RunOptions const TF_Buffer* run_options, // Input tensors const TF_Output* inputs, TF_Tensor* const* input_values, int ninputs, // Output tensors const TF_Output* outputs, TF_Tensor** output_values, int noutputs, // Target operations const TF_Operation* const* target_opers, int ntargets, // RunMetadata TF_Buffer* run_metadata, // Output status TF_Status*);" ^ self ffiCall: #(void TF_SessionRun #(void* aTF_Session, void* opsTF_Buffer, void* inTF_OutputArray, void* inTF_TensorArray, int inCount, void* outTF_OutputArray, void* outTF_TensorArrayPtr, int outCount, void* aTF_OperationArray, int targetCount, void* metaTF_Buffer, void* aTF_Status)) module: TensorFlowCAPI but still have some error: "Could not coerce arguments" .... First method was called by : TF_Session>>runOutputs: aTF_OutputArray size: anInteger | status outvalues | status := TF_Status create. outvalues := FFIExternalArray externalNewType: 'TF_Tensor*' size: anInteger. self library runSession: self getHandle options: FFIExternalObject null inputs: FFIExternalObject null values: FFIExternalObject null count: 0 outputs: aTF_OutputArray getHandle values: outvalues getHandle count: anInteger targets: FFIExternalObject null count: 0 metadata: FFIExternalObject null status: status getHandle. status check. ^ outvalues called by: TF_Session>>runOutputs: anArrayOfTF_Outputs | outputs | outputs := FFIExternalArray externalNewType: 'TF_Output' fromArray: anArrayOfTF_Outputs. ^ self runOutputs: outputs size: anArrayOfTF_Outputs size called by : TF_Session>>runOutput: aTF_Output | results | results := self runOutputs: {aTF_Output}. ^ results first called by : testGraphZeros | graph session result zeros values | graph := TF_Graph create. zeros := graph zerosShaped: #(100 100 10). session := TF_Session on: graph. result := session runOutput: (zeros output: 0). values := result allFloats. self assert: #(100 100 10) equals: result shape. self assert: 100 * 100 * 10 equals: values size. self assert: 0 equals: values min. self assert: 0 equals: values max I'm a bit desperated :-( And impossible to know where the problem come from ... -- Serge Stinckwich UMI UMMISCO 209 (SU/IRD/UY1) "Programs must be written for people to read, and only incidentally for machines to execute."http://www.doesnotunderstand.org/

April 27, 2018

Re: [Pharo-users] [Pharo-dev] libfreetype6 missing in the dependencies of ubuntu Pharo distribution

by Peter UhnÃ¡k

Thanks :) I was testing it on behalf of someone else, so no problems for me. :) Cheers, Peter On Fri, Apr 27, 2018 at 3:30 PM, Holger Freyther <holger(a)freyther.de> wrote: > > > > On 27. Apr 2018, at 19:22, Peter UhnÃ¡k <i.uhnak(a)gmail.com> wrote: > > > > I've installed both ( apt install pharo6-32-ui pharo6-64-ui ), but the > font problem was present only for 32bit. > > > > Note that I was launching the VM packaged with ZeroConf installation, > I've only used apt mainly to get all dependencies. > > > > Now I tried to also run "pharo6-32-ui Pharo.image" (and "pharo6-64-ui > Pharo.image"), > > and in both cases I got errror > > > > "/usr/bin/pharo6-32-ui: line 6: /usr/lib/i386-linux-gnu/pharo6-vm/pharo: > No such file or directory > > > > and > > > > "/usr/bin/pharo6-64-ui: line 6: /usr/lib/x86_64-linux-gnu/pharo6-vm/pharo: > No such file or directory > > What's missing is that pharo6-32-ui should depend on pharo6-32. And the > later package has the dependency on libssl and libfreetype and provides the > "pharo" binary. > > thanks for pointing that out and sorry you had to experience it. > > > >

April 27, 2018

Re: [Pharo-users] FileStream deprecation in Pharo7

by Sven Van Caekenberghe

> On 27 Apr 2018, at 15:28, Sean P. DeNigris <sean(a)clipperadams.com> wrote: > > Sven Van Caekenberghe-2 wrote >> The answer is simple: use FileSystem, it has been in the image for years. > > IIUC the thrust of the question was how to get exactly that info most > effectively to a naive user who runs into the deprecationâ¦ Yes, I understand that that was part of the question, but I don't know what to say about that.

April 27, 2018

Re: [Pharo-users] Literals

by ClÃ©ment Bera

Not really. You can use ClassVariables though. Here's an example for Sets: Object subclass: #MyClass instanceVariableNames: '' classVariableNames: 'MyClassVar' package: 'MyPackage' MyClass class>>initialize super initialize. MyClassVar := Set new. MyClass>>foo self bar: MyClassVar Obviously sets are not as easy to deal with. You cannot mutate empty arrays/bytearrays, if you concatenate something it creates a new object. You can add things in sets. So you need to be careful... You can make the object read-only to avoid issues (MyClassVar beReadOnlyObject). On Fri, Apr 27, 2018 at 3:19 PM, Debiller 777 <ozovozovozo202(a)gmail.com> wrote: > You know, literals are quite useful in case when you want to shorten some > object initialization. For example #() and {} for arrays and $[]for byte > arrays. However, if there is a way to add custom literals, for example for > sets (something like #{} I guess)? how to do it? and can some special kind > of objects for creating literals easily be added to Pharo? > -- ClÃ©ment BÃ©ra https://clementbera.github.io/ https://clementbera.wordpress.com/

April 27, 2018

Re: [Pharo-users] [Voyage] Possible to save an OrderedCollection?

by sergio ruiz

Hi, esteban.. In this case, the persisted object is TestBox.. it does show up just fine in Mongo, but the OrderedCollection of points does not. On April 27, 2018 at 8:57:26 AM, Esteban Lorenzano (estebanlm(a)gmail.com) wrote: what you need to save is the persistent object, the one marked as âisVoyageRootâ in class side. ---- peace, sergio photographer, journalist, visionary Public Key:Â http://bit.ly/29z9fG0 #BitMessageÂ BM-NBaswViL21xqgg9STRJjaJaUoyiNe2dV http://www.codeandmusic.com http://www.twitter.com/sergio_101 http://www.facebook.com/sergio101

April 27, 2018