Re: [Pharo-users] How does Boolean ifTrue work?

[Igor Stasenko]

If you want to ensure that your class(es) comply with certain protocol,
just write a test that covers the protocol and checks that class instances
will understand messages you want it to understand.
But there's no way to restrict your class to comply to whole protocol once
at a time, because tools made in a way, that you populating your class with
methods, each method is add individually and compiled separately, and the
only validation, the compiler is capable of is basically compliance with
smalltalk syntax. And it doesn't cares about higher lever requirement, like
whether your class turns to be 'valid' because of a method you just added,
ready to be used and for what.
Even more, there's no way to connect all those 'interface' formalisation
garbage rules with send sites (the place where you actually invoking one or
another method of one of potetial implementor of your interface), so it
makes no sense to do any (pre)validation on whatever class/object in a
system in order to check whether it conforms with it or not.
That's " Why don't Smalltalk or Smalltalklike languages have checked
interfaces?"
-- 
Best regards,
Igor Stasenko.