[Newbies] Re: Alternative for static const...

[Mispunt]

I am sorry, I did mean execute. I hoped that it would execute
initialize when the class (or variableNames) where called by the
program..
After running/execute the initialize method it is working :)

Thanks for you'r help,

Mispunt

On 2/27/07, Bert Freudenberg <bert at freudenbergs.de> wrote:
> What do you mean with "isn't running"? As I wrote, you have to
> execute it manually whenever you change the initialize method.
>
> - Bert -
>
> On Feb 27, 2007, at 13:33 , Mispunt wrote:
>
> > After some better testing, It doesn't work :S It seems that the
> > initialize of the constants class isn't running... (the normal
> > classVariableNames are working...) I have to use the poolDictionary
> > because there are some codes that return in a lot of classes..
> >
> > Mispunt
> >
> > On 2/27/07, Mispunt <mispunt at users.sourceforge.net> wrote:
> >> Thanks Bert, it works. When I am using the poolDictionary it isn't
> >> possible to use the constants in the Workspace right? or do I have to
> >> write methods for them when I want to use them? (well I don't want
> >> to,
> >> because it is just for testing purpose).
> >>
> >> Mispunt.
> >>
> >> On 2/27/07, Bert Freudenberg <bert at freudenbergs.de> wrote:
> >> > On Feb 27, 2007, at 10:08 , Mispunt wrote:
> >> >
> >> > > Hi all,
> >> > >
> >> > > For programming my Lego Mindstorms NXT I have to use codes
> >> like 16r1F.
> >> > > But I actually want to be able to use "readable" codes. In a
> >> language
> >> > > like Java I will do that with a static const, but as far as I
> >> know I
> >> > > have to do it with symbols in Smalltalk.
> >> >
> >> > No, there is a better way.
> >> >
> >> > If you are inside one class (or its subclasses), you would use
> >> "class
> >> > variables", one per constant. You add them in the class template:
> >> >
> >> > Object subclass: #Bla
> >> >         instanceVariableNames: ''
> >> >         classVariableNames: 'Const1 Const2'
> >> >         poolDictionaries: ''
> >> >         category: 'Bert-Bla'
> >> >
> >> > and the initialization code is in a class-side #initialize method:
> >> >
> >> > initialize
> >> >         "self initialize"
> >> >         Const1 := 16r1F.
> >> >         Const2 := 12345.
> >> >
> >> > You need to execute the "self initialize" in the browser to do the
> >> > initialization. It will be executed automatically when loaded into
> >> > another image.
> >> >
> >> > Class variables are capitalized because they are sort-of "global",
> >> > they can be used in the defining class, its metaclass, and all
> >> their
> >> > subclasses. If you need to give access to these variables across
> >> the
> >> > class hierarchies, then you would do the same, but as a subclass of
> >> > SharedPool:
> >> >
> >> > SharedPool subclass: #BlaConstants
> >> >         instanceVariableNames: ''
> >> >         classVariableNames: 'Const1 Const2'
> >> >         poolDictionaries: ''
> >> >         category: 'Bert-Bla'.
> >> >
> >> > To use this "pool" of variables in another class, list it as a
> >> "pool
> >> > dictionary":
> >> >
> >> > Object subclass: #Bla
> >> >         instanceVariableNames: ''
> >> >         classVariableNames: ''
> >> >         poolDictionaries: 'BlaConstants'
> >> >         category: 'Bert-Bla'
> >> >
> >> > This makes all class variables of BlaConstants available to Bla
> >> as if
> >> > they were class variables.
> >> >
> >> > There are quite a few other ways to allow "global" variables in
> >> > Smalltalk, but this one is the "clean" way to do it which works
> >> > nicely with tools like Monticello.
> >> >
> >> > - Bert -
> >> >
>
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