Params::Validate::validation_options( 
    normalize_keys => sub { $_[0] =~ s/^-//; lc $_[0] }
);

##</code><code>##

my %specs_for = (
    foo =>
      # specify a type
      { type => ARRAYREF },

    bar =>
      # specify an interface
      { can => [ 'print', 'flush', 'frobnicate' ] },

    baz =>
      { type => SCALAR,   # a scalar ...
        # ... that is a plain integer ...
        regex => qr/^\d+$/,
        callbacks =>
        { # ... and smaller than 90
          'less than 90' => sub { shift() < 90 },
      },
);

sub wibble {
    my %args = validate( @_, {
       foo => $specs_for{foo},
       bar => $specs_for{baz},
    });
   # ...
}