I'll add a small bit to Davide's excellent answer, by way of connecting some of the dots. In particular, the browser makes a class look like one thing and we talk about instance side and class side.
The reality is that the browser presents either the class' behaviours or the metaclass' behaviours, depending on whether we have chosen to see "the instance side" or "the class side". Admittedly, the names we use for the sides add to the possible confusion. On Sat, Dec 12, 2020, 12:20 Davide Grandi <davide.gra...@email.it> wrote: > Objects are instances of a class. > Classes are objects, so they have methods. > 'self class' returns the class of self. > > If a class doesn't have a methods ... > ... the search continues in the superclass. > (every class has a superclass ... apart from Object). > > If you download the Blue Book - "Smalltalk-80 - The language and it's > implementation", > it's free on the net, you'll find an AWSOME explanation and diagram from > page 270 on, until ... > ... the final map : classes and metaclass. > > but you've to read it these pages, before. There's a 'metaclass' concept > to acquire. > > Bon voyage ! > > Davide > On 12/12/2020 20:20, g_patrickb--- via Pharo-users wrote: > > I understand if you have Class A with methods p and q that you can call q > from p doing: > > self q > > But there are some cases where a method doesn’t exist but self is still > used. I found a tutorial on creating a Reddit type app and it had a .mcz > which I loaded. > > Here is an example from Class StLoggedInComponent and method refreshReport: > > self report rows: (self session user tasks select: self filterBlock). > > There is a method ‘report’ so I understand that, but there is no method > named ‘session’ so what is the use of self? > > And Class StDatabase has method ‘updateTask:’ has: > > self subclassResponsibility. > > But no method called ‘subclassResponsibility’ exists in the Class. > > Also, Class StLoggedInComponents has method ‘testTasks’ with this: > > ^ self class testTasks > > What is ‘self class’? > > Thank you. > > -- > Ing. Davide Grandi > linkedin : http://linkedin.com/in/davidegrandi > >
