So *b = *a copies those pointers, and undef *a wipes out the original collection of pointers, but not the copy.

That is not true, typeglob assignment performs an aliasing operation:

$x = 10;
@x = qw(1 2 3);

*y = *x;
$x = 12;
print $y;  # <- Prints 12

undef $x;
print $y;  # <- Warns "Use of uninitialized value in..."

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See perlmod

citromatik

In reply to Re^2: Tell me how it works! by citromatik
in thread Tell me how it works! by nagalenoj

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