In the case of for my $x (1) { }, the variable $x is a reference to the value in brackets which is constant.

Consider this: perl -le "my $y = 2; for my $x ($y) { $x = 1; print $y }" When we change $x, we change the underlying $y. So the output is 1

In reply to Re: Modification of a read-only value attempted?!? by Bod
in thread Modification of a read-only value attempted?!? by kikuchiyo

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