What do you really want to do? The dereference is as simple as undef @$ref; (see below for the entire updated sub), but I have the strong feeling that you are asking the wrong question and providing the wrong sample code. It seems extraordinary that you would call a sub just to clear an array!

sub undef_ref {
    my $ref    = shift;
    undef @$ref;
    print '=' x 20;
    print "\n";
    print Dumper (@$ref);
}

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True laziness is hard work

In reply to Re^3: passing reference to subroutine by GrandFather
in thread passing reference to subroutine by asthaonard

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