Le 31/10/2016 à 15:32, CodeDmitry a écrit :
I realized it a bit before you posted but thanks for confirming.
Boolean seems to indeed just be a "Dynamic Interface"; since Smalltalk does
not have "Java Interfaces"(nor want them for the same reason JavaScript
doesn't), the developers wanted to still have True and False be subclasses
of Booleans.
Boolean is a nice header for classification. Everybody is familiar with
Boolean algebra, including hardware guys :)
In all honesty Boolean seems to be there purely for the "common sense" of
it, rather than need. Smalltalk is duck typed and has no need for
interfaces. If it's a Boolean, you know it has those methods so Boolean is
not actually useful for anything; True and False may as well just be
subclasses of Object.
Not exactly. Boolean carry 15 methods that are not overridden in either
False nor True (and 11 methods which are), so Boolean is also used as a
way to share code between the classes True and False and avoid code
duplication. A nice case for having a common superclass below Object.
Thierry
