May 2014 - Pharo-users - lists.pharo.org

Re: [Pharo-users] Domaintalk - PDF Files
by Bob Williams May 13, 2014

May 13, 2014

I received the following comment: My interest is in understanding the utility of such a proposal in enterprise context viz: say in Banking Can Domain driven DSL provide a plausible power user interface for Banking apps driven primarily by UI screens and backend processes. MathsDomain specially may have an appeal in that direction. I responded: My concept of Domaintalk is that it would not be limited to one particular platform, but used on a wide range of platforms; in you example both for the PC, tablet, workstation and mainframe or server, maybe even phones. Its use would be open ended, limited only by the users' imagination. A simple example should suffice to convey my meaning, while not a domain per se, Digitalk's Smalltalk/V used a global dictionary to open up the OS2 and Windows APIs to the programmer, even allowing the user to extend the APIs made available; moreover, all of the OS specific attributes, like handles, were made available. Something that was not available in ObjectWorks and I am not sure is available int Pharo. If domains were added to Pharo, then I am sure someone working on the Pharo internals (VM) could make the OS APIs available and provide a means to add new ones. Such a domain would not even require exposure of the OS attributes of the window because the programmer could simply create their own windows. A word of caution, this would mean that use of that OS specific domain would limit the application to that specific platform; however, that is something that I am willing to live with, in fact, it is something I desire, then I could give the application user the UI that they expect, the one that matches their platform. I can see where a banking application could benefit from the SQL Domain and the Math Domain decimal class and methods, I recall the heavy use of the decimal data and instructions in the IBM mainframes. I can even envision a domain that wrapped the windowing API that made it more usable, so that someone could create another domain that used that domain to add a language that would make window creation easier, either a graphical window builder (similar to the WindowBuilder application of Smalltalk/V) or a scripting type language. The term banking congers up many things to me, of course there is the standard banking account transaction processing, but there also the investment side of the business and other backroom analytical functions. I believe that application for all those diverse requirement could benefit from Domaintalk. For about thirteen year I was the head of computer departments with multimillion dollar IBM MVS mainframes. One thing that I could count on was that when I took over a new department I would find a staff that though that programs always had bugs the they would need to fix. I always seemed that 40% of my programming resources was spend fixing bugs. (Just like the ObamaCare web site.) I established the policy that programmers created bugs, not programs, and implemented step to eliminate all bugs, including having the heads of projects that had bugs meet with me each morning for a very uncomfortable meeting. I took about six months to get the level of bugs down to an acceptable level, about 5%, and mostly in programs scheduled for replacement. So I am well aware of what is required for an enterprise quality application. One reason I want Domaintalk is that, I have observed that, code that is not readable lends itself to errors. Another observation is that when the syntax of a language is stretched beyond its intended use, it become unreadable. I apologize for the lengthy response and I look forward to your response, and answer to the DSL question. BW

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Problem learning about Magritte
by PBK Research May 13, 2014

May 13, 2014

Hello Sorry if this is the wrong place to ask this. I am trying to understand how Magritte works, initially by following the first example in Ch. 26.2 of the Seaside book. I have started with a fresh download of Pharo 3.0, and I have installed Magritte 3 and Seaside 3. I realise that the Seaside book example is based on Magritte 2, so I have made necessary changes to the example code (descriptions are on the instance side, insert <magritteDescription> pragmas, change #description to #magritteDescription). All works well up to the point where I try to generate the Seaside editor. This fails because the code: Address example1 asComponent produces a 'does not understand' message for #asComponent. I have not been able to work through all of Seaside to see where this method is defined, and I am at a bit of a loss. I know this is rather elementary, but could someone give me a pointer? Also, if Magritte 3 is now the norm, will the Seaside book examples be updated to reflect this? Thanks in advance for any help Peter Kenny

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Re: [Pharo-users] Problem learning about Magritte
by Stephan Eggermont May 12, 2014

May 12, 2014

Esteban wrote: >I don't like this "faster way" of prebuilt images. >Makes me think of seeds for forked branches. >Unless something is wrong with the package system, I would encourage >its use, even if it takes long. I strongly encourage the use of ci images. And of course you should add your own, once you've decided what packages you need. The main advantage is that it provides feedback to the core pharo development on changes. Stephan

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Changed semantics for mongo ObjectID
by Norbert Hartl May 12, 2014

May 12, 2014

I needed to change the way ObjectIds are read from and written to BSON. BSON is a format that encodes its byte contents little endian. In mongo database the format of ObjectIds is different. The way an ObjectId is encoded is big endian. You can see this if you compare the outputs for an object when read from mongo shell and from pharo. The ids wonât match. If you do ânormalâ stuff with mongo it is unlikely you have noticed the effect. An OID is read the wrong way but also written the wrong way which makes it right again from the mongo database perspective. But it wonât work if you use a mixed query setting. Meaning reading an OID and requesting the database using javascript expression. This will fail. Iâm writing this because Iâm not sure the change can break existing software. The change is not included in the stable version, yet. If you want to test then load #bleedingEdge and report any problem that might occur. I will use the new behaviour and will take the freedom to make it stable if it works for some time. FYI, Norbert

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Pillar book-skeleton and more
by Yuriy Tymchuk May 12, 2014

May 12, 2014

Dear everyone, Iâm happy to announce about the Pillar book-skeleton project https://github.com/pillar-markup/book-skeleton, which is essentially a generalised starting point for writing books in Pillar. Pharo for the Enterprise and Updated Pharo by Example are using it now. If you have any suggestions, please contribute, or open issues. Together with that weâve created the GitHub organisation named Pillar-markup https://github.com/pillar-markup, which contains pillar-related projects like editor mods and documentation. If you have any Pillar related projectâs we will be happy to add you and the projects to the organisation. Have a nice week. Uko

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Domaintalk - PDF Files
by Bob Williams May 11, 2014

May 11, 2014

I decided to rewrite the Domaintalk proposal and the develop a Math Domain document. To do it correctly I had to use LaTeX which I have not used in decades. But it was worth the effort because it gave me more ideas about how to implement the Math Domain and it produces PDF files. I do not want to clutter this email area, nor your in baskets, so those that would like to see the document and provide comments which I welcome and need. Please reply to email account and I will send you a return email with three attachments: Domaintalk.pdf, MathDomainSpec.pdf and Mapping to Smalltalk Code.htm. bw

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Creating a subclass from nautilus/Pharo3
by Hilaire Fernandes May 11, 2014

May 11, 2014

Hi, In Nautilus, to creat a subclass I have to go in menu Class 'Refactoring>Class Refactoring>Generate Subclass...' (Why is it refactring? It seems NOT for me), anyway I can input a subclass name, then I have this strange dialog with a broken morph. Screen shot enclosed. Hilaire -- Dr. Geo http://drgeo.eu

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Error compiling DrGeo in pahro3
by Hilaire Fernandes May 11, 2014

May 11, 2014

Hi, I got this error when compiling DrGeo in Pharo3 (screenshot). There is not debug log. Thanks Hilaire -- Dr. Geo http://drgeo.eu

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Re: [Pharo-users] Best/simplest way to read and write to a MySQL database
by Andy Burnett May 11, 2014

May 11, 2014

á§ Thanks everyone, I shall try the DBXTalk approach. It seems as though it is being actively developed. As a side note, I think it would be great if Pharo could identify a 'main stream' route for dealing with RDBMS. It would be similar to the way in which Zinc is the main way to do http etc. I wouldn't want to discourage anyone from doing interestng experiments, it's just that a main stream route would help people to get going. Cheers Andy

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May 8, 2014

Hi, I try to use Tabs with Spec and i would like to remove a tab from the TabManagerModel but it doesn't work. TabManagerModel has a method named #removeTab: which call directly its adapter but the MorphicTabManagerAdapter hasn't the method #removeTab: ... I looked at the TabManager class and its the same, no method to remove a tab. A small example I would like to do : The only solution (or rather a hack) i found it's to add an extension like that: anyone have a clue to do that nicer? And other mistery, why the tabBar is removed when the last tab is closed ? If someone can enlighten me. Regards, ----- Glenn CavarlÃ© -- View this message in context: http://forum.world.st/Spec-Tabs-how-to-remove-proramatically-a-tab-tp475800… Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

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