Why doesn't this work as I expect? 
my %h = (a,b,c,d);
&func(\%h);

while ((my $key, my $val) = each %h)
{
  print "key is $key val is $val\n";
}

sub func
{
   $_->{'e'} = 'f';
}

[download]

The output is 
key is c val is d
key is a val is b

[download]
but I also want it to print out
key is e val is f

How can I get it to produce what I want?

In reply to directly modify hash from subroutine by marksman

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