November 2016 - Pharo-users

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

by Esteban Lorenzano

> On 1 Nov 2016, at 11:39, jtuchel(a)objektfabrik.de wrote: > > Am 01.11.16 um 11:36 schrieb Denis Kudriashov: >> >> 2016-11-01 11:31 GMT+01:00 jtuchel(a)objektfabrik.de <mailto:jtuchel@objektfabrik.de> <jtuchel(a)objektfabrik.de <mailto:jtuchel@objektfabrik.de>>: >> ifEmpty: >> ifNotEmpty: >> ifEmpty:ifNotEmpty: >> >> It is already in image and feels exactly like ifNil:/ifNotNil. For other cases I think it is too much. > are they also implemented in UndefinedObject? no, because empty != nil Esteban

Nov. 1, 2016

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

by stepharo

more than that. You can define code in Boolean in terms of the abstract methods and such code will be executed on instance of True and False using False and True methods. You are learning now for real what is OOP. So your teacher is a really smart teacher because he chose to expose you to objects and OOP thinking for real. Stef Le 31/10/16 Ã 15:58, CodeDmitry a Ã©crit : > 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). > > > > -- > View this message in context: http://forum.world.st/How-does-Boolean-ifTrue-work-tp4920873p4920896.html > Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com. > >

Nov. 1, 2016

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

by jtuchel＠objektfabrik.de

Am 01.11.16 um 11:36 schrieb Denis Kudriashov: > > 2016-11-01 11:31 GMT+01:00 jtuchel(a)objektfabrik.de > <mailto:jtuchel@objektfabrik.de> <jtuchel(a)objektfabrik.de > <mailto:jtuchel@objektfabrik.de>>: > > ifEmpty: > ifNotEmpty: > ifEmpty:ifNotEmpty: > > > It is already in image and feels exactly like ifNil:/ifNotNil. For > other cases I think it is too much. are they also implemented in UndefinedObject?

Nov. 1, 2016

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

by Denis Kudriashov

2016-11-01 11:31 GMT+01:00 jtuchel(a)objektfabrik.de <jtuchel(a)objektfabrik.de> : > ifEmpty: > ifNotEmpty: > ifEmpty:ifNotEmpty: > It is already in image and feels exactly like ifNil:/ifNotNil. For other cases I think it is too much.

Nov. 1, 2016

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

by jtuchel＠objektfabrik.de

Phil, I see your point but disagree. I don't use Pharo regularly, so I cannot currently check if the implementation around this emptiness check is complete. With complete I mean that following your logic, theere should be at least implementations of ifEmpty: ifNotEmpty: ifEmpty:ifNotEmpty: ifEmptyOrNil: ifEmptyOrNil:otherwise: I really have to check for the size of collections very often, and the size of 1 is a very frequent case. So why not add: ifExactlyOne: ifSizeIs:do: ifSizeIsGreaterThan:do:otherwiseDo: You get the picture. I strongly believe this leads to pollution and ends up in a mess. We could save so much typing and make our programs so much more readable if we only were a bit more creative, right? ;-) A DSL is another story, though. If you write a Library that makes handling Collections nicer, this is okay and the methods are good to exist in its context. But they shouldn't necessarily all be part of the base image. Don't get me wrong: if you and the Pharo community agree on lots of convenience methods, that is okay for me, and I find myself adding such methods to VA Smalltalk from time to time. I appreciate many of them being brought to VA ST in Grease. Sometimes, this is simply a question of taste, sometimes it saves typing, sometimes it helps to improve readability of code. But I wouldn't go so far to tell people they should better use such a method as a general advice. I would probably tell them: "look, here's a method I find much more elegant, you could *also* use that to save typing/increase readability". Just my 2 cents, and highly off topic ;-) Joachim Am 01.11.16 um 08:43 schrieb phil(a)highoctane.be: > Because I grew tired of the isEmpty ifTrue: [ ] all over the place. > And ifEmpty has the right semantics for my use cases (like assignment). > > I do not really care about portability, I am doing Pharo only. > > Phil > > On Mon, Oct 31, 2016 at 5:30 PM, jtuchel(a)objektfabrik.de > <mailto:jtuchel@objektfabrik.de> <jtuchel(a)objektfabrik.de > <mailto:jtuchel@objektfabrik.de>> wrote: > > Am 31.10.16 um 15:59 schrieb phil(a)highoctane.be > <mailto:phil@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 Tuchelmailto:jtuchel@objektfabrik.de > Fliederweg 1http://www.objektfabrik.de > D-71640 Ludwigsburghttp://joachimtuchel.wordpress.com > <http://joachimtuchel.wordpress.com> > Telefon: +49 7141 56 10 86 0 Fax: +49 7141 56 10 86 1 > -- ----------------------------------------------------------------------- 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

Nov. 1, 2016

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

by phil＠highoctane.be

Because I grew tired of the isEmpty ifTrue: [ ] all over the place. And ifEmpty has the right semantics for my use cases (like assignment). I do not really care about portability, I am doing Pharo only. Phil On Mon, Oct 31, 2016 at 5:30 PM, jtuchel(a)objektfabrik.de < jtuchel(a)objektfabrik.de> wrote: > 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 <jtuchel(a)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 > > >

Nov. 1, 2016