Re^2: Use of freed value

call($x++, $x++) works in an unsurprising manner.

$ perl -e'$x=3; CORE::say for $x++, $x++'
3
4
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I think you're referring to the oddities of call(++$x, ++$x).

$ perl -e'$x=3; CORE::say for ++$x, ++$x'
5
5
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$ perl -e'$x=3; CORE::say for $x, $x++'
4
3
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These occur because $x and ++$x (and --$x) add the scalar $x itself to the stack rather than a copy. $x++ (and $x--) necessarily add a copy of the original value.

Well, the problem is related to the scalars themselves being on the stack, so the explanations are indeed related. But that's just the precondition for the problem, not the answer itself.

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Re^3: Use of freed value by LanX (Saint) on Jun 26, 2019 at 17:25 UTC
> I think you're referring to the oddities of Yes > so the explanations are indeed related. But that's just the precondition for the problem, not the answer itself. Well I tend to avoid such side effects because of this experience. I don't necessarily need to know why I suffer after crossing the red line. Update And it's a pretty good guess inside the 15 min window you left us before answering it yourself. ;) Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery FootballPerl is like chess, only without the dice}	[reply]
Re^4: Use of freed value by ikegami (Patriarch) on Jun 27, 2019 at 11:48 UTC
Well I tend to avoid such side effects because of this experience. hum? We use the side effects of putting the actual scalars on the stack all the time (e.g. `$x = 3;`). I presume you mean you avoid using writing to the scalar twice in the same statement, and avoid writing to the same scalar twice in the same statement. The thing is, `@a, @a=()` doesn't do that, at least not any more than `splice(@a)` or `shift(@a)` do, and I'm pretty sure you don't avoid those.	[reply] [d/l] [select]
Re^5: Use of freed value by LanX (Saint) on Jun 27, 2019 at 22:43 UTC
> I'm pretty sure you don't avoid those. I rarely chain statements having side effects with the coma operator. Only exception are one liners. Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery FootballPerl is like chess, only without the dice}	[reply]
Re^6: Use of freed value by ikegami (Patriarch) on Jun 28, 2019 at 08:44 UTC
Re^7: Use of freed value by LanX (Saint) on Jun 28, 2019 at 11:28 UTC

Update