The program

perl -le 'for my $x (1) {$x = pack "I", $x}'

produces the warning "Modification of a read-only value attempted at -e line 1". But why? Where is the read-only value?

For contrast, perl -le 'for my $x (0..1) {$x = pack "I", $x}' doesn't warn.

In reply to Modification of a read-only value attempted?!? by kikuchiyo

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