Another way to do it (this won't fail if your array contains undefs): 
my @a = ( 1 .. 4, undef, 6 .. 10 );

while (@a) {
  my $x = shift @a;
  say defined $x ? $x : 'undef';
}

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In reply to Re: Why does a full iteration over array & shift is not emptying the array by rubasov
in thread Why does a full iteration over array & shift is not emptying the array by Anonymous Monk

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