August 2013 - Pharo-users - lists.pharo.org

your opinion about storing FixedDecimal in Mongo

by Sabine KnÃ¶fel

Hi, I am interested in your opinion. I use FixedDecimal for computing currency amounts. This works fine. When storing the amounts with voyage into mongo (I have a lot of them!!!), normally, one currency amount would be stored into mongo as follows: "vatAmountEUR": { "#instanceOf": "FixedDecimal", "negative": false, "number": NumberInt(90280), "part1": NumberInt(9), "part2": NumberInt(280), "scale": NumberInt(4) } I think, this is a lot of stuff for one single value. I tend to convert the FixedDecimal into a Float for storing it. In this case, it would be like this: "vatAmountEUR": 0.7196 When loading, I immediately re-convert it into a FixedDecimal. I would do NO computing with the float(!!). What is your opinion about this (rounding issues, performance, database size etc.)? Do you think, there is something against it? What would you do? Sabine -- View this message in context: http://forum.world.st/your-opinion-about-storing-FixedDecimal-in-Mongo-tp47… Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

Aug. 19, 2013

Re: [Pharo-users] Beginner's question ...

by StÃ©phane Ducasse

There is a tutorial but we should finish it using Spec https://pharo.fogbugz.com/default.asp?W67 We are planning to write a complete one but benjamin should come back from holiday. Note that the difference is not between Smalltalk and X, Y Z the difference is between graphical frameworks: for example in VisualWorks you write application GUI differently than in VisualAge or Pharo. Stef

Aug. 17, 2013

Re: [Pharo-users] Beginner's question ...

by StÃ©phane Ducasse

> Thank you, > > Dr. Geo is a full blown-up application. So far I do not intend to write > soemething like that. Morely I intend to use as less GUI as > necessary/possible. Just simple input-/output in a console window or > something like that. > > But maybe BASIC or Pascal is more suitable for that? > Roland. I would not see why :) You define a package with classes and then use --eval to invoke your class and a message pharo yourimage.image --eval '1+3' prints 4 and this is exactly doing that read this chapter even if it is more general

Aug. 17, 2013

Re: [Pharo-users] Beginner's question ...

by Roland Strasser

On 08/17/2013 08:09 AM, StÃ©phane Ducasse wrote: > Hi roland > > You can run pharo with a UI using the headless mode. in that case you can implement a simple read eval loop > that read from standard input and write on stdout. > You can also use the -eval command line parameter to get a value of a message > > Now you can also define a simple ui and disable all the tools. This requires a bit more > practice. So let us know. There is also the user manager package that let you control some behavior. > > Stef > >>> I have programming experiences with BASIC compilers. I would like to >>> program in a Smalltalk environment; but I have the following newbie's >>> questions: >>> >>> a) Can I deploy an image without all the browsers and other "stuff" - >>> just a plain console program? >>> >>> b) How is it possible to write a console program without gui etc.? >>> >>> Thank you! >>> Roland. >>> >>> >>> >> Hello everybody, >> >> Primarilly I just want to catch some experiences with SmallTalk - which >> so far I find really exceptional. For doing that I just want to use a >> simple input-/output window (could be a 'transcript'?), for something >> like that: >> >> input value >> calculate >> return value >> >> If a gave this image to somebody else, I find it necessary to just give >> the "program" itself, without all the rest of the image (and ide). >> >> Thanks, >> Roland >> >> >> >> -- >> Mag. Roland Strasser >> > > > Thanks, is there any tutorial how to write a GUI window with menues, dialogues etc? It would be very helpful, because Smalltalk is VERY different to other languages (as you know of course). Thanks Roland. -- Mag. Roland Strasser

Aug. 17, 2013

Re: [Pharo-users] Beginner's question ...

by Roland Strasser

On 08/17/2013 07:54 AM, Yuriy Tymchuk wrote: > Hi, > > to make you more familiar with existing pharo applications you can check out: > http://www.drgeo.eu/ > Also Pharo is used for web development. You can follow Sven's tutorial to make some simple web app: > http://zn.stfx.eu/zn/build-and-deploy-1st-webapp/ > > Cheers. > Uko > > > ÐÐ°Ð´ÑÑÐ»Ð°Ð½Ð¾ Ð· iPhone > > 17 ÑÐµÑÐ¿. 2013 Ð¾ 08:32 Roland Strasser <rolstra(a)gmx.at> Ð½Ð°Ð¿Ð¸ÑÐ°Ð²(Ð»Ð°): > >> On 08/16/2013 08:33 PM, Roland Strasser wrote: >>> >>> Hi, >>> >>> I have programming experiences with BASIC compilers. I would like to >>> program in a Smalltalk environment; but I have the following newbie's >>> questions: >>> >>> a) Can I deploy an image without all the browsers and other "stuff" - >>> just a plain console program? >>> >>> b) How is it possible to write a console program without gui etc.? >>> >>> Thank you! >>> Roland. >> Hello everybody, >> >> Primarilly I just want to catch some experiences with SmallTalk - which >> so far I find really exceptional. For doing that I just want to use a >> simple input-/output window (could be a 'transcript'?), for something >> like that: >> >> input value >> calculate >> return value >> >> If a gave this image to somebody else, I find it necessary to just give >> the "program" itself, without all the rest of the image (and ide). >> >> Thanks, >> Roland >> >> >> >> -- >> Mag. Roland Strasser >> > Thank you, Dr. Geo is a full blown-up application. So far I do not intend to write soemething like that. Morely I intend to use as less GUI as necessary/possible. Just simple input-/output in a console window or something like that. But maybe BASIC or Pascal is more suitable for that? Roland. -- Mag. Roland Strasser

Aug. 17, 2013

Re: [Pharo-users] Beginner's question ...

by StÃ©phane Ducasse

Hi roland You can run pharo with a UI using the headless mode. in that case you can implement a simple read eval loop that read from standard input and write on stdout. You can also use the -eval command line parameter to get a value of a message Now you can also define a simple ui and disable all the tools. This requires a bit more practice. So let us know. There is also the user manager package that let you control some behavior. Stef >> I have programming experiences with BASIC compilers. I would like to >> program in a Smalltalk environment; but I have the following newbie's >> questions: >> >> a) Can I deploy an image without all the browsers and other "stuff" - >> just a plain console program? >> >> b) How is it possible to write a console program without gui etc.? >> >> Thank you! >> Roland. >> >> >> > Hello everybody, > > Primarilly I just want to catch some experiences with SmallTalk - which > so far I find really exceptional. For doing that I just want to use a > simple input-/output window (could be a 'transcript'?), for something > like that: > > input value > calculate > return value > > If a gave this image to somebody else, I find it necessary to just give > the "program" itself, without all the rest of the image (and ide). > > Thanks, > Roland > > > > -- > Mag. Roland Strasser >

Aug. 17, 2013

Re: [Pharo-users] Beginner's question ...

by Yuriy Tymchuk

Hi, to make you more familiar with existing pharo applications you can check out: http://www.drgeo.eu/ Also Pharo is used for web development. You can follow Sven's tutorial to make some simple web app: http://zn.stfx.eu/zn/build-and-deploy-1st-webapp/ Cheers. Uko ÐÐ°Ð´ÑÑÐ»Ð°Ð½Ð¾ Ð· iPhone 17 ÑÐµÑÐ¿. 2013 Ð¾ 08:32 Roland Strasser <rolstra(a)gmx.at> Ð½Ð°Ð¿Ð¸ÑÐ°Ð²(Ð»Ð°): > On 08/16/2013 08:33 PM, Roland Strasser wrote: >> >> Hi, >> >> I have programming experiences with BASIC compilers. I would like to >> program in a Smalltalk environment; but I have the following newbie's >> questions: >> >> a) Can I deploy an image without all the browsers and other "stuff" - >> just a plain console program? >> >> b) How is it possible to write a console program without gui etc.? >> >> Thank you! >> Roland. > Hello everybody, > > Primarilly I just want to catch some experiences with SmallTalk - which > so far I find really exceptional. For doing that I just want to use a > simple input-/output window (could be a 'transcript'?), for something > like that: > > input value > calculate > return value > > If a gave this image to somebody else, I find it necessary to just give > the "program" itself, without all the rest of the image (and ide). > > Thanks, > Roland > > > > -- > Mag. Roland Strasser >

Aug. 17, 2013

Re: [Pharo-users] Beginner's question ...

by Roland Strasser

On 08/16/2013 08:33 PM, Roland Strasser wrote: > > Hi, > > I have programming experiences with BASIC compilers. I would like to > program in a Smalltalk environment; but I have the following newbie's > questions: > > a) Can I deploy an image without all the browsers and other "stuff" - > just a plain console program? > > b) How is it possible to write a console program without gui etc.? > > Thank you! > Roland. > > > Hello everybody, Primarilly I just want to catch some experiences with SmallTalk - which so far I find really exceptional. For doing that I just want to use a simple input-/output window (could be a 'transcript'?), for something like that: input value calculate return value If a gave this image to somebody else, I find it necessary to just give the "program" itself, without all the rest of the image (and ide). Thanks, Roland -- Mag. Roland Strasser

Aug. 17, 2013

Re: [Pharo-users] Beginner's question ...

by Sven Van Caekenberghe

Hi Roland, On 16 Aug 2013, at 20:33, Roland Strasser <rolstra(a)gmx.at> wrote: > > Hi, > > I have programming experiences with BASIC compilers. I would like to > program in a Smalltalk environment; but I have the following newbie's > questions: > > a) Can I deploy an image without all the browsers and other "stuff" - > just a plain console program? > > b) How is it possible to write a console program without gui etc.? > > Thank you! > Roland. > Yes, it is perfectly possible to use Pharo Smalltalk to write command line tools. It even works pretty well. But you definitively should use the IDE/GUI during interactive development or you'll miss out on a lot ! Sven -- Sven Van Caekenberghe Proudly supporting Pharo http://pharo.org http://association.pharo.org http://consortium.pharo.org

Aug. 16, 2013

Re: [Pharo-users] Beginner's question ...

by James Foster

Hi Roland, Welcome to Smalltalk. As someone who started with BASIC in the early 1970s, I have seen a few changes in the past 40 years. As you have discovered, the typical Smalltalk experience has a heavy emphasis on a GUI. As to deployment, it is generally more difficult to take things out (browsers, tools, etc.) in Smalltalk than in other environments where there is a more rigid distinction between development and deployment. The first thing to note is that any Pharo image can be deployed with command line arguments that disable the GUI (-vm-display-null and -vm-sound-null). Sometimes we just let the other "stuff" come along for the ride and get ignored. Why go to the trouble to remove it? Next, there is GNU Smalltalk (http://smalltalk.gnu.org/) "The Smalltalk for those who can type"! Check it out. Finally, GemStone/S (http://gemtalksystems.com/index.php/products/gemstones/) is available as a command-line Smalltalk with no native GUI. Let us know what you want your console application to do and we can give more advice. James On Aug 16, 2013, at 11:33 AM, Roland Strasser <rolstra(a)gmx.at> wrote: > > Hi, > > I have programming experiences with BASIC compilers. I would like to > program in a Smalltalk environment; but I have the following newbie's > questions: > > a) Can I deploy an image without all the browsers and other "stuff" - > just a plain console program? > > b) How is it possible to write a console program without gui etc.? > > Thank you! > Roland. > > >

Aug. 16, 2013