Dog class>>newWhite
"Returns a new white instance of receiver."
^self new
color: Color white;
yourself

is equivalent to

Dog class>>newWhite
"Returns a new white instance of receiver.��

| instance |

instance := self new.

instance color: Color white;

^ instance

So this is really when you do not know what a subclass may do with reimplementing color:

so yourself make sure that your extenders can be doing crazy things, your job is good.

On 2 Aug 2020, at 19:55, tbrunz <wild.ideas@gmail.com> wrote:

Got it. Seems like an important point for those who are trying to understand
the difference between instances and classes.

I've gotten strange results myself until I learned that #yourself is an
essential thing...

-t

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