I can't think of a way you can do this.

You can make a class that would be useless to subclass. Just put all instance data in lexicals (i.e. Inside-Out) and check the ref() of $self at each method invocation.

In any case, having a class that can't be subclassed is completely useless by itself. As far as I can see the only reason it's even possible to define such classes in some languages is that under certain circumstances the compiler/runtime can optimize calls - it doesn't have to support (as much) polymorphism.

"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re: A class that cannot be subclassed. by Joost
in thread A class that cannot be subclassed. by kyle

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