Is there a simple/elegant way in Perl to create an anonymous scalar reference? There was a discussion on this subject at anonymous scalar reference, but IMHO, the solutions suggested were either not simple, or not anonymous, or both. As a motivation for this question, let's assume that we have some function 

sub f {
  my $ref=shift;
  ...
  $$ref=4711;
}

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which we are not supposed to modify, and that we want to use in a context where we are NOT interested in the value which is stored via $$ref. Possible invocations would be 
# Solution 1
my $ref;
f(\$ref); # Just don't use $ref afterwards

# Solution 2
f(do{\my$x}); # Not really anonymous, since we have to
              # "invent" a variable name, but at least 
              # blessed by Larry

# Solution 3
f(\[]->[0]);  # Anonymous, but not elegant

# Solution 4
sub NULLREF { \ my $x }
f(NULLREF);# Maybe nice if we use this feature often in our
           # program and use NULLREF consistently, but still
           # not really anonymous

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I know that there are more important problems to solve on this planet, but maybe someone could suggest a really nice improvement over the solutions posted above.

UPDATE:Typo in NULLREF corrected

-- 
Ronald Fischer <ynnor@mm.st>

In reply to Anonymous scalar ref revisited by rovf

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