sub foo { print "foo: @_\n" }
sub bar { print "bar: @_\n" }

sub safe_dispatch {
    my ($dispatch, $name, $params) = @_;

    my ($code, @keys) = @{$dispatch->{$name}};
    my @params = map { $_ => $params->{$_} }
                 grep { exists $params->{$_} }
                 @keys;
    return $code->(@params);
}

my %dispatch = (
    foo => [ \&foo, qw/ foo common / ],
    bar => [ \&bar, qw/ bar common / ],
);

my %params = (
    foo => 1,
    bar => 1,
    common => 1,
);

safe_dispatch(\%dispatch, $_, \%params)
    for qw/ foo bar /;

__END__
foo: foo 1 common 1
bar: bar 1 common 1