Re: tutorial: "doesNotUnderstand" instance variable

Karl a écrit :
> Andrew n marshall wrote:
> > I'm trying to go through the pipsqueak tutorial, but it throws a 
> > doesNotUnderstand error when I try to initialize the exitSides 
> > instance variable the first time.  The browser shows the exitSides 
> > variable (with nil value), so the VM knows its there.
> >
> > This is my class declaration:
> > Object subclass: #BlankCell
> >    instanceVariableNames: 'activeSegments exitSides'
> >    classVariableNames: ''
> >    poolDictionaries: ''
> >    category: 'Laser-Game-Model'
> >
> > This is my init function:
> > initializeExitSides
> >    self exitSides: Dictionary new. 
The error message says that #existSides: doesn't exist. So either you 
create it (the accessor) or you directly affect the instance variable.

BlankCell>>existSide: aDictionary
       existSide := aDictionary

or you replace in you initialize method "self exitSides: Dictionary" new by:
existSide := Dictionary new
> >    self exitSides at: #north put: #south.
> >    self exitSides at: #east put: #west.
> >    self exitSides at: #south put: #north.
> >    self exitSides at: #west put: #east.
> >
> > And a screen shot of my error stack trace is here:
> >  http://www.isi.edu/~amarshal/transfers/squeak_error.png
> > (How do I copy it as text anyway?)
> >
> >
> > Anm
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>
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