(This is not an XY problem, nor something that will go to production; just a question that arose while I was playing with obfuscated code).

Let's declare a constant:

*a = \"cons";
$a = "something";
print "$a\n";
__END__
Modification of a read-only value attempted at - line 2.

[download]

That's expected behaviour. Now, a little twisted:

(undef, *a) = \(undef, "cons");
$a = "something";
print "$a\n";
__END__
something

[download]

Surprise! What's that? Isn't it a constant anymore? Isn't that reference to a list, a list of references to each element? Well, let's make an explicit list of references then:

(undef, *a) = (\undef, \"cons");
$a = "something";
print "$a\n";
__END__
Modification of a read-only value attempted at - line 2.

[download]

This is expected again. But, why does the second snippet behave different?

--
David Serrano

In reply to Ref to a list not being equivalent to a list of refs to each element by Hue-Bond

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