: 1
name: bar
version: 1.0.0
summary: bar
license: MIT
url: http://example.org
email: pkg@example.org
depends:\
liba
{
  prefer
  {
    # Prefer `cli` but can work with `cli` or `gui`.
    #
    config.liba.backend = ($config.origin(config.liba.backend) == 'default' || \
                           ($config.liba.backend != 'cli' && $config.liba.backend != 'gui') \
                           ? 'cli' \
                           : $config.liba.backend)
  }

  accept ($config.liba.backend == 'cli' || $config.liba.backend == 'gui')
}
\
