Postulate: because @_ is a magic variable. Witness two different approaches which worked for me: 
sub foo {
    my $self = shift;
    my @args = @_;
    $self->{bar} = ref ( $_[0] ) ? $_[0] : \@args;
}

[download]
(my preferred approach) 
sub foo {
    my $self = shift;
   $self->{bar} = ref ( $_[0] ) ? $_[0] : [ @_ ];
}

[download]
My suspicion is that @_ gets clobbered (or unset) as soon as you leave the subroutine due to internal Special Magic. You're left holding a reference to an empty variable. Either copy the values out of it, or expand it into an anonymous list.

In reply to Re: Wierdness with a reference to @_ by chromatic
in thread Wierdness with a reference to @_ by Disco Stu

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