And if it is immutable, I simply don't have to care. That's a benefit, because it reduces mental load while programming.

Sorry, but that simply isn't true. There is no reduction in cognitive load in a hybrid environment, because you still have to think about which type you are dealing with every time.

That's not a big issue if you have a clear mental model about what a "value object" and what a mutable object is.

A clear mental model huh.

Perl 5 is a good example: numbers are immutable,

Really?

$i = 1; 
++$i; 
print $i;;
2

[download]

Okay. Bye.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^8: The fallacy of the *requirement* for read-only instance variables. by BrowserUk
in thread The fallacy of the *requirement* for read-only instance variables. by BrowserUk

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