I have a package which has functions with hashref prototypes. An illustrative example: 
sub foo(\%)
{
    my $h = shift;
    # do something with it...
    $h->{"FOO"} = "Hello, world!";
}

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Well, when I use the package and call those functions, they won't work with stuff like the following (Perl nags that I must use a hash and not a hash reference): 
my %stash;

foo(\%stash);

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But calling it with foo(%stash) works. Why is that? The prototype says to expect a hash reference after all. I tried eyeballing through the Perl Cookbook, Learning Perl, Programming Perl and even Advanced Perl Programming but found no help. I have use strict pragma turned on. Am I missing something subtle here? I wish my function prototypes were consistent... Anyone?

In reply to Hash reference question by Anonymous Monk

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