package dispatch;

my %disallowed = (
    security => 1,
);
sub security
{
    # Handle security here, somehow, returning a boolean.
}

# Because we're overloading can(), we can easily make it play nicely with AUTOLOAD.
sub can
{
    my $proto = shift;
    my ($method) = @_;

    return '' if $disallowed{$method};
    UNIVERSAL::can($proto, $method);
}

#### Functions to dispatch to below here

---------------

if (dispatch->security( ... ) and my $method = dispatch->can( ... ))
{
    $method->(@args);
}