I am trying to write a generic 'set' method. A simplified fragment: 
my %drink;
# other attribute hashes

sub set {
   my ($key, $attr, $value) = @_;

   my $hashref;
   eval "\$hashref = \\\%$attr";
   
   if ( !defined $hashref ) {
      carp 'Invalid attribute name';
   }
   else {
      $hashref->{$key} = $value;
   }
}

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The call to this subroutine: 
set('larry', 'drink', 'Old Speckled Hen');

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This does not work, i.e. it does not actually alter the 'real' hash (%drink). I have discover two fixes, but I cannot explain why either works 1. If I stringify the actual hash (%drink). After the assignment, if I add: 
print "$drink{$key}\n";

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it works. It seems to 'commit' $hashref. Using Data::Dumper or Devel::Peek::Dump also fixes it. 2. If I make the hash an 'our' variable it works. I'm setting warnings and use strict. Tried on 5.8.6 on Fedora and 5.8.7 on Windows. What is going on?

In reply to eval a reference to a my hash by cdarke

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