in reply to Assigning list with duplicate keys to hash

In Perl Best Practices, TheDamian recommends using a hash for default parameters like so: 

my %DEFAULTS = ( a => 1, b => 2 );
sub foo {
    my $arg_ref = shift;
    my %args = ref $arg_ref eq ref {} ? ( %DEFAULTS, %{$arg_ref} )
                                      : %DEFAULTS;
}

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He clearly expects the second hash to overwrite the duplicated contents of the first, so I think it's safe to say this is defined behavior that you can rely on.

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Re^2: Assigning list with duplicate keys to hash
by Your Mother (Archbishop) on Apr 22, 2008 at 17:23 UTC

    In his OOP book he gives a much clearer, to me, way to do (almost) the same thing. I use it often. Dovetails nicely with Params::Validate. 

    sub bar {
   my %args = ( mi => "default",
                mo => "default",
                mu => "default",
                @_  # list of args in key/val pairs
              );
# ...
}

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[d/l]

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