Perhaps "bad style" is too strongly put.

But it is certainly considered good style to avoid side-effects. And the advice of thinking of setq as having a penalty associated is straight from On Lisp by Graham. It is not a religious rule. But it is worth thinking about. In fact I think about it in Perl as well, though I am not as extreme because Perl cannot optimize tail recursion.

As for the other point, perhaps I was unclearly verbose. But that is exactly what I was getting at with the phrase "...should no longer affect the value of z."

In reply to Re (tilly) 3: Lisp is More Evaluatable by tilly
in thread Lisp is More Evaluatable by princepawn

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