Thank you for your combined wisdom. I see this also works but looks a bit inelegant. 
 
my @q = ( 1,2,0,4 );
$first = pop @q;
print "q $#q pop ",$first,"->";
while ($#q+1) 
{  $next = pop @q ;  print ",",$next };
---- Gives
q 2 pop 4->,0,2,1

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I would be using the offered solution. 
while( @array )
{ my $next = shift @array; }

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In reply to Re^2: pop and shift not reversible ( while @array ) by gannett
in thread pop and shift not reversible by gannett

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