Your example only shows that variables that contain numbers are mutable. But since you can't do 3 = 5;, or modify the number 3 in any other way, numbers are immutable.

Now you might say that's obvious and not worth discussing, but it does show that not everything is mutable. You can only say that everything is mutable for very limited definitions of "everything", which currently suit your needs.

Perl 6 - second systems done right

In reply to Re^9: The fallacy of the *requirement* for read-only instance variables. by moritz
in thread The fallacy of the *requirement* for read-only instance variables. by BrowserUk

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