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Re: [Pharo-users] How does Boolean ifTrue work?

by jtuchel＠objektfabrik.de

Am 31.10.16 um 16:13 schrieb CodeDmitry: > I meant "dynamic" as a contrast to Java's abstract classes/interfaces which > are going to slap you if you forget to implement one of the abstract > methods, Smalltalk will also slap you if you send an unimplemented message. The only difference is that Java will make you sit down and do your homework first, no matter if you still remember what you wanted to do in the first place ;-) But coming back top the topic: the Boolean superclass is not at all comparable to a Java interface. It does provide implementation and is not only there to force you to first make the compiler happy and then see if you implemented anything useful. Joachim

Oct. 31, 2016

Re: [Pharo-users] How does Boolean ifTrue work?

by jtuchel＠objektfabrik.de

Am 31.10.16 um 15:59 schrieb phil(a)highoctane.be: > but you should use myCollection ifEmpty: [ ... ] interesting. Why do you think so? what if you wanted your code to be portable across Smalltalk dialects? > > > > -- ----------------------------------------------------------------------- Objektfabrik Joachim Tuchel mailto:jtuchel@objektfabrik.de Fliederweg 1 http://www.objektfabrik.de D-71640 Ludwigsburg http://joachimtuchel.wordpress.com Telefon: +49 7141 56 10 86 0 Fax: +49 7141 56 10 86 1

Oct. 31, 2016

Re: [Pharo-users] UDP Socket primitive failure

by Nicolai Hess

Hi, 2016-10-31 12:46 GMT+01:00 Dimitris Chloupis <kilon.alios(a)gmail.com>: > Hey guys I try to use Pharo to use Supercollider via OSC. OSC library is > maintained by Stef in STHub. > > So SC informs that it receives the messages sent, but in Pharo I am > getting annoying Primitive errors that I paste bellow. Anyone knows if this > a bug or something missing here ? > > Also SC sometimes it informs me that the message was received in a > different port than it was sent. > > Here the code I am using > > (OSCMessage for:{'/mixer.volume'. 1 . 0.2})sendTo: '127.0.0.1' port: 57120. > is the 0.2 a float or should this be read as 0 . 2 . (as two integral numbers?). {'/mixer.volume'. 1 . 0.2} asByteArray will try to convert every item in this array to a byte, so it will create a byte array with four items, but it can not convert the string to a single byte. Of course, you can convert a string to a byte array '/mixer.volume' asByteArray "#[47 109 105 120 101 114 46 118 111 108 117 109 101]" > > Any help greatly appreciated. > > Supercollider is an application which is basically a server written in C++ > that does music composition and audio synthesis live , its extremely > powerful and the top professional audio tool for audio synthesis and music > live coding. > > http://supercollider.github.io > > Socket(Object)>>primitiveFailed: > Socket>>errorSending:startingAt:count:toHost:port: > Socket>>primSocket:sendUDPData:toHost:port:startIndex:count: > Socket>>sendUDPData:toHost:port: > OSCMessage(OSCPacket)>>sendTo:port: > UndefinedObject>>DoIt > OpalCompiler>>evaluate > RubSmalltalkEditor>>evaluate:andDo: > RubSmalltalkEditor>>highlightEvaluateAndDo: > [ textMorph textArea editor highlightEvaluateAndDo: ann action. > textMorph shoutStyler style: textMorph text ] in [ textMorph textArea > handleEdit: [ textMorph textArea editor highlightEvaluateAndDo: ann action. > textMorph shoutStyler style: textMorph text ] ] in > GLMMorphicPharoScriptRenderer(GLMMorphicPharoCodeRenderer)>>actOnHighlightAndEvaluate: > in Block: [ textMorph textArea editor highlightEvaluateAndDo...etc... > RubEditingArea(RubAbstractTextArea)>>handleEdit: > [ textMorph textArea > handleEdit: [ textMorph textArea editor highlightEvaluateAndDo: ann action. > textMorph shoutStyler style: textMorph text ] ] in > GLMMorphicPharoScriptRenderer(GLMMorphicPharoCodeRenderer)>>actOnHighlightAndEvaluate: > in Block: [ textMorph textArea... > WorldState>>runStepMethodsIn: > WorldMorph>>runStepMethods > WorldState>>doOneCycleNowFor: > WorldState>>doOneCycleFor: > WorldMorph>>doOneCycle > [ [ World doOneCycle. > Processor yield. > false ] whileFalse: [ ] ] in MorphicUIManager>>spawnNewProcess in Block: > [ [ World doOneCycle.... > [ self value. > Processor terminateActive ] in BlockClosure>>newProcess in Block: [ self > value.... > >

Oct. 31, 2016

Re: [Pharo-users] How does Boolean ifTrue work?

by CodeDmitry

That's a very interesting point; Even if Boolean messages is inlined into True and False, it provides a very convenient place to hook additional messages that are common to True and False to without needing to touch True nor False. -- View this message in context: http://forum.world.st/How-does-Boolean-ifTrue-work-tp4920873p4920910.html Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

Oct. 31, 2016

Re: [Pharo-users] How does Boolean ifTrue work?

by Ben Coman

Hi Dmitry, You've just bumped into one of Smalltalk's paradigms that may change the way you *think* about programming ;). For me it was certainly an eye-opener. It intrigued me there could even exist another way to *think* about booleans. On Mon, Oct 31, 2016 at 10:06 PM, jtuchel(a)objektfabrik.de <jtuchel(a)objektfabrik.de> wrote: > When I teach Smalltalk, this is one of the most beautiful exercises for > students. > Those who get it will love Smalltalk, those who don't often leave the > project soon ;-) Interesting insight. On Mon, Oct 31, 2016 at 10:32 PM, CodeDmitry <dimamakhnin(a)gmail.com> wrote: > Boolean seems to indeed just be a "Dynamic Interface"; since Smalltalk does > not have "Java Interfaces"(nor want them for the same reason JavaScript > doesn't), the developers wanted to still have True and False be subclasses > of Booleans. > > In all honesty Boolean seems to be there purely for the "common sense" of > it, rather than need. Smalltalk is duck typed and has no need for > interfaces. If it's a Boolean, you know it has those methods so Boolean is > not actually useful for anything; True and False may as well just be > subclasses of Object. Not quite. Yes most of Boolean's own methods are mostly subclassResponsibilitys, but you can see Boolean provides a place for extensions by *Fuel, *Reflectivity, *ston-core and *UnifiedFFI packages to hang methods common to both True and False. The best way to properly understand this is to observe it in action yourself, by debugging through it. Except you can't debug it since #ifTrue:#iFalse is inlined for performance. Instead try defining... True>>myifTrue: trueAlternativeBlock ifFalse: falseAlternativeBlock ^trueAlternativeBlock value False>>myifTrue: trueAlternativeBlock ifFalse: falseAlternativeBlock ^falseAlternativeBlock value then from Playground, debug... true myifTrue: [self inform: 'true'] ifFalse: [self inform: 'false']. false myifTrue: [self inform: 'true'] ifFalse: [self inform: 'false']. and just continue stepping <Into>, (except step <Over> the #inform: when you get there) cheers -ben

Oct. 31, 2016

Re: [Pharo-users] How does Boolean ifTrue work?

by Thierry Goubier

Le 31/10/2016 Ã 16:18, Denis Kudriashov a Ã©crit : > > 2016-10-31 16:11 GMT+01:00 Norbert Hartl <norbert(a)hartl.name > <mailto:norbert@hartl.name>>: > >> Am 31.10.2016 um 15:59 schrieb phil(a)highoctane.be >> <mailto:phil@highoctane.be>: >> >> but you should use myCollection ifEmpty: [ ... ] >> > Why? > > > because it shorter :) And when teaching Pharo, you have to explain: Student - What is ifEmpty: ? Teacher - It is the same as isEmpty ifTrue: [ ... Joke apart, it seems, following Esteban remark, that Pharo is gearing towards making life easier to the experienced Smalltalk developper (make it easier to create a collection-like object) and harder for newcomers ... Thierry

Oct. 31, 2016

Re: [Pharo-users] How does Boolean ifTrue work?

by Denis Kudriashov

2016-10-31 16:11 GMT+01:00 Norbert Hartl <norbert(a)hartl.name>: > Am 31.10.2016 um 15:59 schrieb phil(a)highoctane.be: > > but you should use myCollection ifEmpty: [ ... ] > > Why? because it shorter :)

Oct. 31, 2016

Re: [Pharo-users] How does Boolean ifTrue work?

by Esteban A. Maringolo

2016-10-31 12:11 GMT-03:00 Norbert Hartl <norbert(a)hartl.name>: > > Am 31.10.2016 um 15:59 schrieb phil(a)highoctane.be: > > but you should use myCollection ifEmpty: [ ... ] > > Why? It enables you to implement polymorphism with an object that might not be aCollection, but behaves like one. Of course you could also implement #isEmpty, but in my experience the less you test (#isEmpty) and the more you delegate (ifEmpty:) the better. :) Regards, Esteban A. Maringolo

Oct. 31, 2016

Re: [Pharo-users] How does Boolean ifTrue work?

by CodeDmitry

I meant "dynamic" as a contrast to Java's abstract classes/interfaces which are going to slap you if you forget to implement one of the abstract methods, so the only reason to define the methods that are going to be overwritten seems to be to disambiguate the error message that will be raised from the selector not being there. -- View this message in context: http://forum.world.st/How-does-Boolean-ifTrue-work-tp4920873p4920905.html Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

Oct. 31, 2016

Re: [Pharo-users] How does Boolean ifTrue work?

by Esteban A. Maringolo

2016-10-31 11:58 GMT-03:00 CodeDmitry <dimamakhnin(a)gmail.com>: > Ah so it's more of a "dynamic abstract class" than a "dynamic interface", so > they do get visited during the traversal of the inheritence chain(rather > than skipped immediately to Object). I don't know what you mean by "dynamic". The whole object system of Smalltalk is dynamic by design. Esteban A. Maringolo

Oct. 31, 2016