While i can't seem to come up with a simple example to demonstrate it, my feeling is that this line: @SLIDERVALUES = (5, 10, 15, 20); results in the 5,10,15,20 being stored in a different place (address).. i.e. that you've pulled the rug out from uder the \$SLIDERVALUES[$i] pointers.. That answer is consistent with direct changes like $SLIDERVALUES[1] = 14; working, but i realize it's still kind of hand-waving... Hopefully another monk can clarify from here..

Here's some code that shows in short the funniest coding on:

my @x = ( 1, 2, 3, 4);
my $v = \$x[2];
warn $v;
warn "v = " . $$v;
warn "  " . $_ . " " . \$_ for @x;

@x = ( 5, 12, 13, 14);
warn $v;
warn "v = " . $$v;
warn "  " . $_ . " " . \$_ for @x;
__END__
SCALAR(0x80fbc5c) at /tmp/arr line 6.
v = 3 at /tmp/arr line 7.
  1 SCALAR(0x80fbb0c) at /tmp/arr line 8.
  2 SCALAR(0x80fbc14) at /tmp/arr line 8.
  3 SCALAR(0x80fbc5c) at /tmp/arr line 8.
  4 SCALAR(0x8120634) at /tmp/arr line 8.
SCALAR(0x80fbc5c) at /tmp/arr line 11.
v = 3 at /tmp/arr line 12.
  5 SCALAR(0x80fbb0c) at /tmp/arr line 13.
  12 SCALAR(0x80fbc14) at /tmp/arr line 13.
  13 SCALAR(0x8120634) at /tmp/arr line 13.
  14 SCALAR(0x810531c) at /tmp/arr line 13.
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