Posted by
Sven Van Caekenberghe-2 on
Jan 20, 2016; 2:17pm
URL: https://forum.world.st/Updating-a-project-and-NIL-class-variables-tp4872905p4872926.html
> On 20 Jan 2016, at 15:34, Dimitris Chloupis <
[hidden email]> wrote:
>
> Thank you for the info but I think I did not make myself clear because you say "remain nil"
>
> Ok Imagine a class SomeClass and that class has a variable we will call SomeVariable, class variable that is
> , there is no class initialize method, now that class has a method that is eventually called ,
> someMethod
>
> SomeVariable ifNil: [ SomeVariable := 'hello world']
>
> so when I decide to update this class via metacello loading the latest version from github , SomeVariable will have the value 'hello world'
>
> My question is , will SomeVariable after I do the update revert back to nil or stay 'hello world' ?
>
> If your answer is no, and it stays 'hello world' then yes i need an initialize method and call it at update time.
Argh, I should have said: keeps it value, will not revert to nil.
Sorry for the confusion !
> On Wed, Jan 20, 2016 at 2:54 PM Sven Van Caekenberghe <
[hidden email]> wrote:
> They remain nil.
>
> That is why #initialize on the class side is needed.
>
> You can call that explicitly in a post load script, or rely on the class loading mechanism that normally calls #initialize automatically when loading a class. The warning is: this only happens when the *source* code of the #initialize methods changes. So sometimes, you will have to touch that method to force it.
>
> I hope that makes sense.
>
> See MCMethodDefinition>>#postloadOver:
>
> > On 20 Jan 2016, at 13:41, Dimitris Chloupis <
[hidden email]> wrote:
> >
> > So my question is this , I have a class with nil variables that are lazy initialised only when needed the first time and of course they keep their values from there on.
> >
> > Lets say I get the latest update from github via metacello over an older update that I already have inside the image , do those variables revert back to nil values ? or do they keep their values as they are ?
>
>