This is interesting.. an empty hash is false, but an empty hash reference.. is TRUE. :-) 
#!/usr/bin/perl -w
my %hash = ();
%hash or print "empty hash is false\n";

my $hash = {};
print "empty hash ref is true\n" if $hash ;

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In reply to Re^2: param = 0, not NULL by leocharre
in thread param = 0, not NULL by Spenser

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